DavidLochbaumisthedirectoroftheUnionofConcernedScientists’NuclearSafetyProjectandtheauthorofNuclearWasteDisposalCrisis.

EdwinLymanisaseniorscientistintheGlobalSecurityProgramoftheUnionofConcernedScientists.

JournalistSusanQ.StranahanwasamemberofthePhiladelphiaInquirerteamawardeda1980PulitzerPrizeforitscoverageoftheThreeMileIslandaccident.

The Union of Concerned Scientists is the leading science-based nonprofitworkingforahealthyenvironmentandasaferworld.

©2014byUnionofConcernedScientistsIntroduction©2015byUnionofConcernedScientistsAllrightsreserved.Nopartofthisbookmaybereproduced,inanyform,withoutwrittenpermissionfromthepublisher.

Requestsforpermissiontoreproduceselectionsfromthisbookshouldbemailedto:PermissionsDepartment,TheNewPress,120WallStreet,31stfloor,NewYork,NY10005.

FirstpublishedintheUnitedStatesbyTheNewPress,NewYork,2014ThispaperbackeditionpublishedbyTheNewPress,2015DistributedbyPerseusDistributionISBN978-1-62097-118-5(e-book)LIBRARYOFCONGRESSCATALOGING-IN-PUBLICATIONDATALochbaum,DavidA.

Fukushima:thestoryofanucleardisaster/DavidLochbaum,EdwinLyman,SusanQ.Stranahan,andtheUnionofConcernedScientists.

p. cm.Includesbibliographicalreferencesandindex.1.FukushimaNuclearDisaster,Japan,2011.2.Nuclearpowerplants—Accidents—Japan—

Fukushima-ken.I.UnionofConcernedScientists.II.Title.TK1365.J3L632014363.17'990952117—dc23

2013035284TheNewPresspublishesbooksthatpromoteandenrichpublicdiscussionandunderstandingoftheissuesvitaltoourdemocracyandtoamoreequitableworld.Thesebooksaremadepossiblebytheenthusiasmofourreaders;thesupportofacommittedgroupofdonors,largeandsmall;thecollaborationofourmanypartnersintheindependentmediaandthenot-for-profitsector;booksellers,whooftenhand-sellNewPressbooks;librarians;andaboveallbyourauthors.

www.thenewpress.com

Compositionbydix!ThisbookwassetinMinion

10 9 8 7 6 5 4 3 2 1

CONTENTS

IntroductiontothePaperbackEdition

1. March11,2011:“ASituationThatWeHadNeverImagined”

2. March12,2011:“ThisMayGetReallyUgly...”

3. March12Through14,2011:“WhattheHellIsGoingOn?”

4. March15Through18,2011:“It’sGoingtoGetWorse...”

5. Interlude—SearchingforAnswers:“People...AreReachingtheLimitofAnxietyandAnger”

6. March19Through20,2011:“GiveMetheWorstCase”

7. AnotherMarch,AnotherNation,AnotherMeltdown

8. March21ThroughDecember2011:“TheSafetyMeasures...AreInadequate”

9. UnreasonableAssurances

10. “ThisIsaClosedMeeting.Right?”

11. 2012:“TheGovernmentOwesthePublicaClearandConvincingAnswer”

12. ARapidlyClosingWindowofOpportunity

Appendix:TheFukushimaPostmortem:WhatHappened?

Glossary

KeyIndividuals

U.S.BoilingWaterReactorswith“MarkI”and“MarkII”Containments

NotesandReferences

Index

INTRODUCTIONTOTHEPAPERBACKEDITION

Nearly four years have passed since the accident at the Fukushima Daiichinuclear plant in Japan. Since that time, the long-term environmental andeconomic consequencesof the accident and themagnitudeof the effort itwilltaketoaddressthemhavecomeintosharperfocus.WhileTokyoElectricPowerCompany(TEPCO)hasalmostcompletedremovalofthespentfuelassembliesfrom their precarious perch in Unit 4, the inability to contain the vast andgrowingquantityofcontaminatedwaterattheplantsitehasemergedasoneofthebiggestproblemsthatJapanisfacing.Waterbeingpumpedintothereactorsto cool the damaged cores continues to leak out through cracks in thecontainmentstructureswhilehundredsofgallonsofgroundwaterflowunderthesiteeveryday,washingradioactivecontaminationintothesea.TEPCOdoesnothavethecapacitytocollectandtreatallofthiswater.Itisconstructingasystemtofreezeamile-longwallofsoilaroundthecontaminatedareainordertodivertgroundwaterflow,butthatmaynotwork.Preliminaryattemptstofreezeamuchsmallerareahavefailed.

Although more details about the accident and its aftermath have come tolight,thefundamentalelementsofthisdisasterremainthesame:atrioofreactorcores inmeltdown; an extended loss of all power; vulnerable pools of deadlyspent fuel at risk of boiling dry; radiation threatening large swaths of Japan,including Tokyo, the world’s most populous metropolis, and potentially evenparts of the United States. Images of reactor buildings exploding, stories ofheroic efforts to save the plant, poignant accounts of families uprooted fromtheirhomesandheritage, andcommunities rendereduninhabitablewill remainvividinthepublicconsciousnessforyearstocome.

ThestoryofFukushimaDaiichiisalargertale,however.Itisthesagaofatechnologypromotedthroughthecarefulnurturingofamyth:themythofsafety.Nuclearpowerisanenergychoicethatgambleswithdisaster.

FukushimaDaiichiunmaskedtheweaknessesofnuclearpowerplantdesign

and the long-standing flaws in operations and regulatory oversight. AlthoughJapanmustshare theblame, thiswasnotaJapanesenuclearaccident; itwasanuclearaccidentthatjusthappenedtohaveoccurredinJapan.TheproblemsthatledtothedisasteratFukushimaDaiichiexistwhereverreactorsoperate.

ThestaffoftheU.S.NuclearRegulatoryCommission(NRC)appeartohavefinallyacceptedthisaswell,concludinginaNovember2013reportthatevenifJapan had the same regulatory framework as the United States prior to theaccident, there is no assurance “that the Fukushima accident and associatedconsequencescouldorwouldhavebeencompletelyavoided.”

Although the accident involved a failure of technology, even moreworrisomewas the roleof theworldwidenuclear establishment: the close-knitculturethathaschampionednuclearenergy—politically,economically,socially—while refusing to acknowledge and reduce the risks that accompany itsoperation. Time and again, warning signs were ignored and near misses withcalamitywrittenoff.

ImportantlessonsfromFukushimaDaiichicontinuetoemerge.TEPCOnowbelieves thatcoredamageatUnit3wasmoreextensive than ithadpreviouslyestimated because the emergency core cooling system in the Unit 3 reactorstopped working earlier than it had thought. Consequently, the core becameuncoveredaround2:30a.m.onMarch13,ratherthan9:00a.m.,aswereportedinthebook.AndTEPCOisnowconvincedthatacontainmentfailureatUnit2onMarch15,coupledwithanunfavorableweatherpattern,wasthecauseoftheextensive radiationcontamination to thenorthwestof the site.However,muchstillremainsunknownaboutwhathappenedinsidetheJapanesenuclearplant.

Alsounclear is themagnitudeof the long-termeffectsof radiationreleasesonhumanhealthandtheenvironment,aswellastheultimateeconomicimpact.Basedona2014estimateof the total radiationdose to theJapanesepublicforeightyyearsaftertheaccidentbytheUNScientificCommitteeontheEffectsofAtomicRadiation, a few thousand cancer deaths could be expected.However,the ultimate human toll depends on the fate of the more than one hundredthousandevacueeswhoremaindisplacedbecausetheirhomesarecontaminated.The Japanese authorities could limit future radiation exposures by enforcingstrict cleanup standardsbefore allowing the evacuees to return to their homes,but instead they are declaring areas safe where radiation levels are ten timesgreaterthannormalbackgroundlevels.

One thing is certain: absent the valiant and tireless efforts of many atFukushimaDaiichi,theconsequencescouldhavebeenmuch,muchworse.

Fukushima Daiichi provided the world with a sobering look at a nuclearaccidentplayingout in real time.LikepreviousaccidentsatThreeMile IslandandChernobyl, theevents thatbeganonMarch11,2011,defied thecomputersimulations and glib assurances of nuclear power promoters that this form ofenergyisaprudentandlow-riskinvestment.Itcannothopetofulfillthatclaimabsentanunwaveringanduncompromisingcommitmenttosafety.

Excuses about this accident flew almost from the outset. Nobody hadpredictedanearthquakethislarge.Nobodyhadexpectedahugetsunamitofloodalow-lyingcoastalnuclearplant.Nobodyhadenvisionedanaccidentinvolvingmultiple reactors.Nobody had assumed such an event could involve a loss ofpowerformorethanafewhours.Butallofthisdidhappen,andwithinamatterofhourstheassurancesofnuclearsafetywererevealedasafallacy.

Evenso,manyintheUnitedStates,Japan,andelsewherearepushinghardtodefendthestatusquoandholdfasttotheassertionthatsevereaccidentsaresounlikelythattheyrequirescantadvanceplanning.Thosewhomightdifferwiththatview—amongthemthetensofthousandsofJapanesewhoseliveshavebeenradicallyaltered—havethusfarlargelybeenshutoutofthepublicpolicydebateovernuclearpower.

In Japan, the conservative government under Prime Minister Shinzo Abecontinues its push to restart Japan’s nuclear plants as rapidly as possible. TheNuclear Regulation Authority (NRA), which was created in the wake of theaccidenttobolsterthecredibilityoftheJapanesenuclearregulatorysystem,hasbegun the process with its approval of the restart of the Sendai plant on thesouthernislandofKyushu,despiteitslocationthirtymilesawayfromanactivevolcano.QuestionslingerabouttheindependenceoftheNRA,asAbereplacesits initial members with pronuclear individuals with close industry ties. Thegovernment simply seems in denial about the very real potential for anothercatastrophicaccident.

IntheUnitedStates,theNRChasalsocontinuedoperatingindenialmode.Itturneddownapetitionrequestingthatitexpandemergencyevacuationplanningto twenty-fivemiles from nuclear reactors despite the evidence at Fukushimathat dangerous levels of radiation can extend at least that far if a meltdownoccurs.Itdecidedtodonothingabouttheriskoffireatover-stuffedspentfuelpools. And it rejected the main recommendation of its own Near-Term TaskForcetoreviseitsregulatoryframework.TheNRCandtheindustryinsteadarerelying on the flawed FLEX program as a panacea for any and all safetyvulnerabilities that go beyond the “design basis.” This should provide little

comforttothepubliclivingnearthedozensofnuclearplantsaroundtheUnitedStates that are susceptible to earthquakes and floods far larger than theywereoriginallydesignedtowithstand.

Other methods of generating energy also carry risks in terms ofenvironmentalcostsaswellashumanhealthandsafetyimpacts.Butthat isnoexcuse for continuing to hold nuclear power only to the inadequate safetystandards that made the Fukushima disaster possible. Nuclear energy is anunforgivingtechnology,andtheconsequencesofamistakecanbecatastrophic.

This book is a collaboration. It weaves a detailed explanation of what wentwronginsidethecripplednuclearplanttogetherwithanarrativeofeventstakingplaceinthehallsofgovernmentinTokyoandtheemergencyoperationscenterof the NRC. It reveals how those responsible for protecting the public in theUnitedStatesandJapanwerecaughtunpreparedandoftenhelpless.

Of equal importance, the book describes the nuclear establishment’smultidecadeeffort toweakensafetyrulesandregulatoryoversight,especially in theUnitedStates.Indoingso,thisbookanswersthequestionheardsoofteninthiscountryintheaftermathofMarch11,2011:canithappenhere?Theanswerisanunequivocalyes.

Fukushima:TheStoryofaNuclearDisasteralsoaddressesanothercriticalquestion:howcanweworktowardensuringthatitneverdoes?

Theminute-by-minuteaccountofeventsatFukushimaDaiichi,as revealedby conversations among the nuclear experts, gives the average reader a rareglimpseintojusthowcomplexanuclearaccidentcanbe—andhowill-equippedregulatorsandtheindustryaretodealwithone,nomatterwhereittakesplace.Absentsignificantupgradesinnuclearoperationandregulation,itwillbeonlyamatteroftimeuntiltheworldwatchesasanotherFukushimaunfolds.

ProfoundthanksgotoMaryLoweKennedy,whoseskillsasaneditorrunverydeep. She jumped into a book about nuclear safety with enthusiasm, with adedication that never flagged, andwith the sharedgoal ofmaking this a storyunderstandabletoallwhorememberFukushimaandwanttolearnmore.

Special thanks also go to three members of the Union of ConcernedScientists’staff:StephenYoungfortakingtheinitiativetolaunchtheprojectandLisbeth Gronlund and DavidWright for their counsel and commentary. PeterBradfordgenerouslyprovidedhisinsights,asdidCharlesCasto,whosefirsthand

knowledge of the accident added a valuable dimension to the book. YuriKageyamaoftheTokyobureauoftheAssociatedPressgenerouslyvolunteeredhertime,helpingwithtranslationandresearch.

Thanks also toKatjaHering for her support and assistancewith obtainingdocuments,andtoRhodaandAndreaLymanfortheirsupportforthisproject.

EdwinLymanandSusanQ.StranahanOctober2014

1

MARCH11,2011:“ASITUATIONTHATWEHADNEVERIMAGINED”

At2:49 p.m., the chandeliers began to sway in an ornate hearing roomof theDietBuilding,home toJapan’sparliament.PrimeMinisterNaotoKanglancednervouslytowardthehighceiling.Legislatorsdartedabout,theirvoicesrisingasthe shaking increased.One speaker advisedeveryone toduckunder thedesks.Aideshurriedtotheprimeminister’sside,uncertainwheresafetyactuallylay.

NHK, Japan’s public broadcasting system,was televising theKanhearing.Asanunsteadycameracapturedtheconfusioninthehearingroom,thenetworkwas receiving an earthquake alert from the Japan Meteorological Agency.Ground-motionsensorsalongthecoastnearSendai,northofTokyo,hadpickedupseismicactivityoffshore.Basedonthosereadings,theagencyestimatedthatamagnitude7.9quakewas likely. In thirtyseconds itdispatchedawarning toresidents along the northeastern coast. Personal cell phones lit up.Businesses,schools, hospitals, and the news media all received alerts; twenty-four bullettrainsoperatingintheregionglidedtoahalt.

Within ninety seconds,NHKhad interrupted its coverage to provide earlydetails about the quake. Almost instantly, TV screens across Japan begandisplayingemergencyinformation.

In Sendai, an NHK cameraman hopped aboard the helicopter kept onpermanent standby for thenetworkand liftedoff from theairport. Itwouldbeperhapsthelastaircrafttodepartthefacilitybeforetheearthquakecrisistookadramaticturnfortheworse.Thefootageshotfromthathelicopterwouldsoonbereplayedagainandagainaroundtheworld.

Japansitsatoponeofthemostearthquake-proneregionsoftheworld,shakenby

morethanathousandtremorseachyear.TheancientJapanesebelievedagiantcatfish lay buried beneath the islands. When the creature thrashed about, theearth moved. Modern scientists have their own explanation: several massiveplatesof theearth’scrustabuteachotheraround the islandsof Japan, shiftingcontinuouslyafewinchesperyear.Iftheirmovementisimpeded,stressbuildsuntilitisreleasedinaseismicevent.Thateventmaybebarelydetectable—oritcanbecatastrophic.

Along the northeastern coast, thewestward-moving Pacific Plate is forcedbeneath the North American Plate that holds most of northern Japan. Thisdownward movement along a seam in the earth’s surface is known assubduction. It is responsible for producing some of the world’s largestearthquakes.

AmapofJapanshowingthemajorcities.Perry-CastañedaLibraryMapCollection,UniversityofTexas

Although northeastern Japan is no stranger to earthquakes, seismologistslongbelievedthatasubductionquakewasunlikelytohappentherebecausethe140-million-year-old Pacific Plate was sliding downward smoothly, nevercreating a huge buildup of stress.Unbeknownst to them, however, sections ofthe two plates had locked together, possibly for as long as a thousand years,

whilepressurecontinuedtobuild.At 2:46 p.m. on March 11, 2011, about eighty miles offshore, the strain

along the tightly squeezed plate surfaces finally became too great. Like astubborn load winched too tightly, the Pacific Plate broke free and lurcheddownwardwitha jerk.That freed theNorthAmericanPlate to springupward,the pressure relieved.Along a seamofmore than 180miles, thePacific Platedroppedat anangle,moving100 to130 feetwestwardas theoverlyingNorthAmericanPlateroseupandangledeastwardthesamedistance.

Withinmoments,thenorthernhalfoftheislandofHonshu,Japan’slargest,wasstretchedmorethanthreefeettotheeast,amovementoflandmasssogreattheearth’saxisshiftedbyseveralinches.

Earthquakessendoutpacketsofenergyinasuccessiveseriesofwaves.Firstcome the bodywaves,which travel through the entire body of the earth. Thefastestbodywavesareprimary(P)waves,whicharenondestructiveand travelthree or fourmiles per second. This is the groundmotion Japan’s earthquakeearly-warning sensors detect. P waves are followed by secondary (S) waves,which travel at about half the speed but have the potential to cause moredamage.FollowingthePandSbodywavesaretheevenslowersurfacewaves,which cause themost severe groundmotion and are responsible for themostdamage to surface structures. The lead time provided by P waves is crucialbecause even a fewminutes’ advance notice allows people to seek safety andcriticalsystemstoshutdown.

Japan’searthquakewarningnetworkisregardedasthebest intheworld.Itwas created in the aftermath of the 1995 Kobe earthquake in western Japan,whichkilledmore than five thousandpeople.The system reliesona thousandground-motion sensors around the country that canpinpoint the locationof anearthquakewithinasecondortwoandinmostcasesestimateitsmagnitudeasfast.

OnMarch11,sensorsnearSendaidetectedthefirstoffshoretremorswithineight seconds and transmitted the information to the Japan MeteorologicalAgency190milesawayinTokyo.Just twodaysbefore, fourquakeshadbeenmeasuredinthissameareaofseabed.Thelargesthadamagnitudeof7.3,whichwasnothingoutof theordinarybyJapanesestandards.1Seismologists thoughtthatthestresshadbeenrelievedandtheearthhadsettledbacktonormal.Now,however, the sensors were recording an even larger quake, with an estimatedmagnitudeof7.9.

For all of its technological prowess, Japan’s early-warning system has aprovenweakspot:becauseof itsspeed, thesystembroadcastswarningsbeforeallseismicdatahavearrived,andthusittendstosignificantlyunderestimatethesize of an earthquake. Although a 7.9 magnitude quake could produce majordamage,itwasnotbeyondwhatJapanhadoftenexperiencedbefore.

Butnaturewasthrowingtechnologyacurveball.

The Fukushima Daiichi nuclear power station in 2010. The exhaust stacks between Units 1 and 2 andbetweenUnits 3 and 4 can be used to discharge radioactive gas vented from the containment structureduring an emergency. Administrative buildings, including the emergency response center and SeismicIsolationBuilding,arelocatedbehindUnit1.TokyoElectricPowerCompany

The shaking continued for about three minutes, an unusually long time.About seventy-five seconds in, longafter the systemhad sentout analert, themassiveunderseaplatesslidapart, releasingcascadingamountsofenergy.TheU.S. Geological Survey would later estimate that enough surface energy wasthrown off by the rupture to power a city the size ofLosAngeles for a year.Over several days, the Japan Meteorological Agency upgraded the quake,ultimatelytomagnitude9,forty-fivetimesmoreenergeticthantheoriginal7.9prediction. This was the largest earthquake ever recorded with instruments in

Japan and one of the five most powerful in the world since modern recordkeepingbeganin1900.

On a forested stretch of the coast south of Sendai, seismic sensors at TokyoElectric Power Company’s Fukushima Daiichi Nuclear Power Station alsoregisteredthePwaves.Atforty-sixsecondspast2:46p.m.,themotioncausedasensorontheUnit1reactortotrip.Twelvesecondslater,anothersensoronUnit1tripped.Thereactorbegantoshutdownautomatically,justasitwasdesignedtodo.At2:47,analarmalertedcontrolroomoperatorstoUnit1’sstatus:“ALLCRFULLIN.”2Theninety-sevencontrol rods—thebrakes thathalt anuclearchain reaction—were fully inserted into thecore.Units2and3 soon followedsuit.Inaboutaminute,thethreeoperatingreactorsatFukushimaDaiichiwereinshutdown. (The other three reactors at Fukushima Daiichi, Units 4, 5, and 6,wereoutofserviceforroutinemaintenance.)Elsewherealongthenortheasterncoast,eightreactorsatthreeothernuclearplantsalsoautomaticallyshutdown.ItwaswhatU.S.reactoroperatorscalla“vanillascram”—ashutdowndonebythebook.

Fukushima Daiichi has six boiling water reactors (BWR), designed in the1960sandearly1970sby theGeneralElectricCorporation(GE)andmarketedaround theworld.This typeof reactorproduceselectricitybyboilingwater tomakesteamtoturnaturbinegenerator.Threefactorsareatwork:theamountofwater,itstemperature,anditspressure.

As thewatercirculatesaround theferociouslyhotcore, it turns intosteam.Thesteam,underpressure,movesthroughpipestotheturbinegenerators.Afterforcingtheturbinesaround,thesteamflowsdownintoacondenser,whereitiscooled, converted back to water, and then recirculated through the core. Toolittlewater in the core and the fuel rods can overheat and boil dry; toomuchsteam,andpressurebuildstounsafelevels.

Thenuclear fuel used in the reactors consists of uraniumoxidebaked intoceramicpellets.Thesepellets are formed into fuel rodsby inserting them intothirteen-foot-longtubes(or“cladding”)madeofametallicalloycontainingtheelement zirconium, which contains radioactive gases produced in the fissionprocess.

The fuel rods are assembled into rectangular boxes known as fuelassemblies, which are then arranged in an array approximately fourteen feetwide within a six-inch-thick steel reactor vessel. The reactor vessel itself is

locatedwithin another structure called a drywell,which is part of the primarycontainment structure. In “Mark I” BWRs like Fukushima Daiichi Units 1through 5, the drywell ismade of a steel shell surrounded by steel-reinforcedconcrete. This shell is a nearly impermeable barrier designed to containradioactivityintheeventofanaccident.

TheMarkIboilingwaterreactor.U.S.NuclearRegulatoryCommission

Anotherpartoftheprimarycontainment,thewetwell,sitsbelowthedrywellandisconnectedtoitthroughaseriesofpipes.Halffilledwithwaterandoftencalleda torusbecauseof itsdoughnutshape, thissystemisdesigned toreducepressurebydrawingoffexcesssteamandcondensingitbacktowater.Withoutthe “energy sponge” provided by the torus, the primary containment structurewouldhavetobefivetimeslarger—andthusmoreexpensive—towithstandthesameamountofenergyreleasedduringanaccident.

Finally, the primary containment is surrounded by another structure, thereactor building, known as the “secondary containment.”Although the reactorbuildingcanhelptocontainradioactivity,thatisnotitsmainpurpose.

Theceramicfuelpellets,thezirconiumalloycladding,thereactorvessel,the

primarycontainment, and the reactorbuildingconstitute a seriesof layers thatareintendedtopreventthereleaseofradioactivitytotheenvironment.However,as theworldwouldsoonwitnessatFukushimaDaiichi, thesebarrierswerenomatchforcertaincatastrophicevents.

•••

Aftera scram, the reactoroperators’primary job in the first tenminutesofanabnormaleventistoverifythatappropriateautomaticactionsaretakingplaceastheplantshutsitselfdown.However,withnuclearreactors,thesafetychallengescontinueaftertheoffswitchisflipped.Althoughthechainreactionhasstoppedanduraniumnucleiarenolongerundergoingfission,thefuelinthereactorcorescontinuestogenerateahugeamountofheatfromthedecayoffissionproducts,unstable isotopes producedwhen the reactorwas operating. Therefore, pumpsdrivenbyelectricmotorsarestillneeded tocirculatecoolingwateraround thenuclearfuelandtransfertheheatenergytowhatengineerscallthe“ultimateheatsink”—inthiscase,thePacificOcean.

If cooling is lost, in as little as thirty minutes the water level within thereactorvesseldropsaboutfifteenfeetandfallsbelowthetopsofthenuclearfuelrods.Soonafterward,theexposedrodsoverheat,swell,andburst.Thezirconiumalloy cladding reactswith steam and generates potentially explosive hydrogengas.Thetemperatureofthefuelpelletscontinuestoriseuntiltheybegintomelt,emittingmoreradioactivegasesintothereactorvessel.Afterseveralhours,themeltingcoreslumpsanddropstothebottomofthevessel.Themoltenfuelissocorrosivethatwithinafewhoursitburnscompletelythroughthesix-inchsteelwall.

Once the reactorvessel is breached, the fuel flows through to the concretefloor of the primary containment, where it reacts violently with the concrete,churning out additional gases. At this point, any of several mechanisms cancausetheprimarycontainmenttofail,eitherrapidlythroughviolentexplosionsorslowlythroughgradualoverpressure.Thelastbarriertotheenvironment—thereactorbuilding—maycontainsomeoftheradiationbutcannotbecountedontodo so. The end result: the release of plumes of radioactive material andcontaminationoftheenvironment.

InadditiontomorethantwohundredtonsoffuelinthecoresofUnits1,2,and3 combined, the FukushimaDaiichi site stored hundreds of tons of irradiated

fuel that had been discharged from the reactor cores andwas now being keptunderwaterinswimmingpool–likestructuresateachofthesixreactorsandinacommon pool nearby. Most of this was “spent fuel” no longer useful forgenerating electricity. Someolder spent fuelwas stored in “dry” concrete andsteel storage casks. Even though the spent fuel rods in the pools had beenremovedfromthereactorcoresmonthsorevenyearsearlier,theystillgeneratedenoughdecayheattorequireactivecoolingsystems.

Ordinarily, theelectricityneededtopowerthecoolingsystemsforboththescrammed reactors and the spent fuel poolswould come fromoff-site throughthe power grid. However, conditions on March 11 were far from ordinarybecauseoftheearthquake,whichhadtoppledelectricaltransmissiontowersanddamagedpowerlines.Insidetheircontrolrooms,joltedbythetremors,operatorsat Fukushima Daiichi could only surmise what was happening in the worldbeyond. They nowwatched theirmonitors as temperature and pressure in thereactorsdecreased.

Intheeventthattheprimarycoolingsystemfails,boilingwaterreactorshaveauxiliary systems. Fukushima Daiichi Unit 1 had isolation condensers: largetanksofwaterdesignedtoprovideanoutletforsteamfromthereactorvesselifit becomes blocked from its normal path to the turbine condenser. The otherreactors were each equipped with a “reactor core isolation cooling” system,knownasRCIC(pronouncedrick-sea),whichispoweredbysteamandcanrunreliably without AC power as long as batteries are available to provide DCpower to the indicators and controls.3 In addition, BWRs are equipped withemergencycorecoolingsystemsshouldtheprimaryandauxiliarysystemsfail.

Justbefore2:48,astheshakingworsened,alarmsintheUnit1controlroomsignaled that power had been lost to the circuits that connected to the off-sitepowergrid.Likehomesandbusinessesallalongthebatteredcoast, thereactorwas nowwithout external power. The lights flickered asUnit 1 and the otherreactors were automatically transferred from the external power supply to theon-site emergency system. Within seconds, Fukushima Daiichi’s thirteenemergency diesel generators (two per reactor, plus a third at Unit 6)automatically fired up. This restored the power, instrumentation, and coolingequipmentneededtokeepthenuclearfuelfromoverheating.

Atthesametime,theturbinegeneratorsatUnits1,2,and3shutdown,andthe valves carrying steam to the turbines automatically closed, as they weresupposed to do after a scram. At Unit 1, a rise in pressure was halted five

minuteslater,atabout2:52p.m.,whenothervalvesautomaticallyopened—alsoasexpected—andallowedthesteamtoflowintotheisolationcondensers.Abouttenminuteslater,operatorsmanagedtostarttheRCICsystemsatUnits2and3.

Onceagainpressurelevelsheadeddownward,asdidwatertemperatures.Butjust as heat and pressure spikes pose a threat to hardware in a reactor, so dorapidly falling temperatures; both can cause metal to expand or contract tooquicklyandultimatelybreakbecauseofhigh stress.At3:04p.m., fearing thatthe Unit 1 reactor was cooling too fast, control room operators followedproceduresandshutdowntheisolationcondensers,figuringtheycouldbeturnedbackonwhenneeded.

•••

Whenthetremorshadsubsided,FukushimaDaiichiworkersassembledforarollcall in the parking lot in front of the main office building, which had beendamaged by the shaking. Those assigned emergency management duties thenmoved to the plant’s emergency response center on the second floor of theearthquake-proofSeismic IsolationBuildingnextdoor.From there, theycouldcommunicatewithoperatorsinthecontrolrooms,whoconfirmedthatUnits1,2,and3hadsuccessfullyshutdown.

But the earthquake was just nature’s first assault. The next was about tostrike. The quake’s hypocenter was located eighteen miles beneath the oceanfloor,buttheruptureangledupwardthroughthecrust,reachingtheseabedandreshaping it.Thatdisplacedamountainofwater.Somewasnowheadingeastintotheopenocean.(BythetimethewaveshitAntarctica,abouteightthousandmilessouthoftheepicenter,theystillhadenoughpowertobreakoffmorethanfifty squaremilesof ice shelf, twice the areaofManhattan.)Waveswere alsoracing westward—headed straight for northeastern Honshu at the speed of ajetliner.

Barelyaswellon theocean’ssurface, thehugesurgeofwaterwouldslowwhenithitshallowerdepthsbutthenrearupandintensify,strikingnotoncebutmultipletimes.JustastheJapanesearenostrangerstoearthquakes,theyknowwellthepowerofthemassivewavethatthey—andtherestoftheworld—callatsunami.

ThenortheasternshoulderofHonshuisknownastheTohokuregion,aremotemountainousareathatincludes,fromnorthtosouth,theprefecturesofAomori,

Iwate, Miyagi, and Fukushima. While the region near Fukushima Daiichi isrelativelyflat,elsewheresteephillsidesandjaggedinletssheltersmallfishingorfarmingvillages.TheportionnorthofFukushimaisknownastheSanrikuCoastandishometosomeofJapan’smostspectacularsceneryandrenownedseafood.

For earth scientists, however, the name Sanriku is synonymous with theconvulsive forces of nature, as evidenced by a June 1896 earthquake andtsunami, the deadliest in Japan’smodern history.Amagnitude 7.2 earthquakestruckoffshore,rattlingthecoastbutcausingnoalarm.Thirty-fiveminuteslater,atabout8:00p.m.,theoceansuddenlyrecededhundredsofyards,thenreturnedasawallofwaterthatdestroyedeverythinginitspath.Thewave,estimatedat125feethighinplaces,killed22,000peoplealongtheSanrikuCoastandsweptawayentirevillages.4

Japan’swritten recordsof earthquakesgoback to 599A.D. anddocumentone that struck Sanriku in July 869 A.D., known as the Jogan earthquake.Believed to have had amagnitude of about 8.6, it generated a twenty-six-footwavethatsweptinlandatleasttwoandahalfmiles,killingathousandpeople,accordingtoanofficialrecord.

Thatwas the first of asmanyas seventy recorded tsunamis that struck theTohokuregionofJapan.TheMarch2011tsunamithathitSanrikuandareastothesouth, includingFukushimaPrefecture,recordedforty-five-footwaves.TheJapanese have officially designated this disaster the 2011 TohokuokiEarthquake.5 Its toll: nearly nineteen thousand killed or officially declaredmissing.Ofthosedeaths,morethan96percentareattributedtothetsunami.

FukushimaDaiichi’ssitesuperintendent,MasaoYoshida,wasintheemergencyresponse center when he learned from a television broadcast that the tsunamipredictions had been revised upward. Three minutes after the early quakewarnings, the coastal prefectures closest to the epicenter—Iwate,Miyagi, andFukushima—hadbeenalertedtopreparefora“three-meterorhigher”wave(tenfeetorso).Thewavewasnowestimatedatabouttwicethat.Yoshidabegantoworrythatthetsunamimightdamageemergencyseawaterpumpfacilitiesontheshore—the systems needed to carry residual heat away from the reactors andsupport equipment, such as the water-cooled emergency diesel generators.However,heexpectedthateveninthatcasehewouldbeabletocompensatebyusing other available equipment.He could not anticipate the full extent of thedisasterabouttooccur.

At3:27p.m.,forty-oneminutesaftertheearthquakebegan,thefirsttsunamiwavehittheseawallextendingoutwardfromtheFukushimaDaiichiplant.Thewave, thirteen feet high, was easily deflected; the wall had been built towithstandwateralmostthirty-threefeet(tenmeters)high.

At 3:35 p.m., a secondwave struck.This one towered about fifty feet, farhigher than anyonehadplanned for. It destroyed the seawater pumpsYoshidahad worried about and smashed through the large shuttered doors of theoceanfront turbinebuildings,drowningpowerpanels thatdistributedelectricitytopumps,valves,andotherequipment.Itsurgedintothebuildings’basements,where most of the emergency backup generators were housed. (Two workerswouldlaterbediscovereddrownedinoneofthosebasements.)Althoughsomedieselgeneratorsstoodonhigherlevelsandwerenotflooded,thewaverenderedthem unusable by damaging electrical distribution systems. All AC power toUnits1through5hadbeenlost.Innuclearparlance,itwasastationblackout.

TheradioactivewastetreatmentfacilityatFukushimaDaiichiisengulfedinseawaterat3:35p.m.onMarch11,2011,afterawaveaboutfiftyfeethighslammedintothenuclearpowerplant.Theimagebelowshowsthesamesceneoneminutelater.TokyoElectricPowerCompany

Japaneseregulators,liketheircounterpartsaroundtheworld,hadknownfordecades that a station blackoutwas one of themost serious events that couldoccur at a nuclear plant. If AC power were not restored, the plant’s backupbatteries would eventually become exhausted. Without any power to run thepumps and valves needed to provide a steady flow of cooling water, theradioactivefuelwouldoverheat, theremainingwaterwouldboilaway,andthecorewouldproceedinexorablytowardameltdown.

Because Japanese authorities, like those in other countries, believed thepossibility of such a scenario was very remote, they dragged their heels inaddressing this threat. They were confident that the electrical grid and thebackup emergency diesel generators were highly reliable and could be fixedquickly if damaged. They refused to consider scenarios that challenged theseassumptions.

Butinthe1990s,afterU.S.officialsfinallytookactiontoaddresstheriskofstation blackout, Japanese regulators also recommended that plant operatorsdevelop coping procedures.6 These plans took advantage of backup cooling

systemsliketheRCICthatoperatebysteampressurealone,withouttheneedforelectric pumps. But the systems do rely on eight-hour batteries to powerequipment that operators can use to monitor their performance and makeadjustmentstokeepthemstable.CopingwithastationblackoutisessentiallyaraceagainsttimetorestoreACpowerbeforethebatteriesrundown.

AcrossJapan,anetworkofremotecamerasismountedatports,alonghighwaysand bridges, atop buildings, and in other critical areas. On the afternoon ofMarch 11, these cameras provided the world with a real-time view of thedisaster. Under its agreement with the government, NHK could activate thecameras from its newsroom, giving viewers stunning images: fishing boatstossedlikebathtubtoysandwholevillagesconsumedbyravagingwater,milesof mud, and debris. Video uploaded from personal cell phones and webcamsappearedontheInternetwithinseconds.BillionsofpeoplebecameeyewitnessestothenaturalcatastropheunfoldinginJapan.

From a hillside behind the reactor complex to which they had evacuated,employeeswatchedasthemurkygraywaterroaredupandaroundthebuildings.Cars andmachinery bobbed like corks, and debris borne on the surgingwatercrashed into structures likebattering rams.Then,withasmuch forceas it hadslammed into the plant, thewater surgedback into the roilingocean, carryingawayequipmentandleavingenormousdamagebehind.

In the capital, officials at Tokyo Electric Power Company, known asTEPCO,assembledtheirowncommandcenteronthesecondfloorofcorporateheadquarters.Morethantwohundredemployees,hastilysummoned,tooktheirplacesatlongrowsofdesks.

At3:37camethecallfromFukushimaDaiichi.NotonlywasUnit1withoutAC power, but it had also lost DC power: flooding had destroyed its backupbatteries.ThecontrolroomforUnits1and2wentdark;instrumentpanelsfadedto black. All power to these reactors had been lost or couldn’t be deliveredwhereneededbecauseofdamagetopowerpanelsandcables.Thiswasnowthemost severe type of station blackout. Without DC power to control coolingsystemslike the isolationcondenser,onlyaverynarrowtimewindowwas leftbeforecoredamagebegan.

Onebyone,inthespaceofafewminutes,Units1through5lostACpowersupplies,andhigh-voltageelectricalpanelswere flooded. (Onlyonegenerator,located on higher ground nearUnit 6 and cooled by air rather than seawater,continued to work.) For the first time in history, a nuclear accident was

unfoldinginmultiplereactorsatthesametime.This was a situation no one had prepared for—or even thought possible.

TEPCO’sstationblackoutguidelineswereincapableofaddressingthechallengenowplayingout,becausetheyassumedthatonlyoneunitwouldbeaffectedandit could draw on the power supplies of adjacent units. Nor did the guidelinescontemplatethesimultaneouslossofbothACandDCpower.“Weencounteredasituationthatwehadneverimagined,”Yoshidawouldsaylater.

Tocompound thecrisis, these reactorshad justbeensubjected toa record-breakingearthquakeandtsunamithatmayhavecausedstructuraldamage.Andnow,withpowergone, therewasnoway toknowwhatwashappening insidethem.

If a natural disaster could trigger a crisis like the one unfolding at FukushimaDaiichi,then,onemightwonder,whyaren’tevenmoresafetyfeaturesrequiredtopreventsuchacatastrophicthingfromoccurring?

The short answer is that developers of nuclear power historically haveregardedsuchsevereeventsas sounlikely that theyneedn’tbe factored intoanuclear plant’s design. The experts could not imagine that such a cascadingfailure of safety systemswould really occur. So the regulations required onlythat reactors be able to survive conditions occurring during far less severeaccidents, known as “design-basis accidents.”As defined by theU.S.NuclearRegulatoryCommission(NRC),design-basisaccidentswerescenariosthatwereunlikely tooccurduring the lifetimeof anuclear reactorbutwerenonethelessconceivableenoughtowarrantmeasurestolimittheirseverity.Reactordesignsare equipped with emergency cooling systems and containment structuresintended to function during design-basis accidents to limit core damage andradioactivereleasetoalevelregulatorsconsideracceptable.

If these systems don’t work, then the plant enters the realm of “beyonddesign-basis” accidents, also called “severe” accidents. Severe accidentschallenge plant operators in part because they involve complex and poorlyunderstood phenomena. What is known comes primarily from tests andcomputersimulationsthatprovideonlylimitedinsight.Thepostmortemreviewof the 1979 beyond-design-basis loss-of-coolant accident at the Three MileIslandreactor inPennsylvaniaconfirmedsomepredictionsbutraisedquestionsabout others. FukushimaDaiichi has raised evenmore questions, and one dayshouldprovideadditionalanswers.

WellbeforeFukushima,criticsarguedthatpredicatingreactorsafetyontheability to handle design-basis accidents left nuclear plants vulnerable to farworseeventsthataremoreprobablethantheindustrywouldliketobelieveandthan thepublicwouldbewilling toaccept.Evenso,design-basisaccidentsdocreateastiffsetofrequirements.Reactorcontainmentsmustberuggedenoughstructurestowithstandthehighpressuresandtemperaturesthatcouldoccurinadesign-basisaccidentwithoutdevelopinglargeleaksorrupturing.Containmentsaretypicallymadeofsteelshellsorsteel-reinforcedconcretewithleak-tightsteelliners.Becauseoftheirsizeandstrengthrequirements,theydon’tcomecheap.

When GE designed its boiling water reactors, it equipped them with“pressure suppression” containments to reduce construction costs. Thesecontainments featured additional systems for converting excess steam towaterand thus, the theory went, did not need to be built to withstand very highaccidentpressures.

After GE began selling the first boiling water reactors with this feature,safety critics called attention to what they believed was a dangerousvulnerability:thecomplexpressuresuppressionsystemwasnotwellunderstood.Ifitfailedtosufficientlyreducesteampressureduringanaccident,thetoo-smallprimary containment surrounding the reactor vessel might burst, releasingradioactivematerialintotheenvironment.

And that was not the only threat. The Three Mile Island accident raisedawarenessofthedangerofhydrogen.Duringthataccident,hydrogenproducedby the reactionof steamwith the fuel rodcladdingcausedanexplosion in thecontainment.AlthoughtheThreeMileIslandcontainmentwassufficientlylargeand robust towithstand the shock,engineers realized that theexplosionwouldhavebeenpowerfulenoughtorupturethesmaller,weakerpressuresuppressioncontainments. As a result, the NRC required that reactors with pressuresuppression containments be retrofitted to control hydrogen accumulation inaccidents either by filling the containments with nitrogen, an inert gas, or byactivating spark plug–like devices called igniters to gradually burn off anyhydrogen. The Japanese were monitoring U.S. developments closely and alsorequired Mark I containments to be “inerted.” That addressed one accidentcontingency, but neither theNRCnor the Japaneseworried aboutwhatwouldhappenshouldhydrogenescapethecontainmentandleakintootherareasoftheplant.

FukushimaDaiichiUnit1wasaMarkIreactorthatbeganserviceinMarch1971 and ran for forty years.Units 2, 3, 4, and 5weremore advancedBWR

modelsbut alsohadMark I containments.Unit 6was aBWRwith aMark IIcontainment, which also used pressure suppression. Across Japan, there weretwenty-eightboilingwaterreactors.TheUnitedStateshas thirty-five,ofwhichtwenty-threehavetheGEMarkIcontainment.(Seep.279foralist.)

InTokyo,PrimeMinisterKanwasalsostrugglingtograspwhatwashappening.Thecapitalhadn’tbeenincludedintheinitialearthquakealertbecausetheJapanMeteorological Agency had underestimated the earthquake’s size andsubsequenthazardzone.ButwhentheshakinghitTokyo,Kanhadhustledoutofthehearingroomandheadedacrossthestreettohisoffice.There,hegatheredasmallgroupofadvisorsinabasementsituationroom.

Kanhadwonelectiontotheofficeofprimeministerjusttenmonthsbefore.AmemberoftheDemocraticPartyofJapan,hehadservedasfinanceministerandhadcampaignedonapromise to improve thenation’sweakeconomy.Healso pledged to lessen the influence of the powerful but unaccountablebureaucracythathaslongrunthegovernment.

When it came to nuclear energy in Japan, that bureaucracy was large.Responsibility was divided among multiple government agencies, whosemissions sometimes overlapped—or conflicted. Japan’s fifty-four commercialnuclear power plants were regulated by the Nuclear and Industrial SafetyAgency (NISA), which operated under the jurisdiction of the Ministry ofEconomy,TradeandIndustry(METI).NISAsharedsomeresponsibilitieswiththeMinistry of Education, Culture, Sports, Science and Technology (MEXT),which had a dual role: to promote nuclear energy and to ensure its safeoperation. MEXT performed environmental radiation monitoring and assistedlocalgovernmentswithradiationtestingintheeventofanaccident.

AlsointhemixwastheNuclearSafetyCommission(NSC),anindependentagencythatoperatedwithintheexecutivebranch.TheNSCsupervisedtheworkofMEXTandMETIandprovidedpolicyguidance,butalsoworkedtopromotenuclear power. And finally, there was the Japan Nuclear Energy SafetyOrganization,whichinspectednuclearfacilities,conductedsafetyreviews,and,inthecaseofanemergency,maderecommendationsonevacuations.

Japan’s prefectures had a role, too. They were responsible for radiationmonitoring anddirecting evacuations if needed.Onpaper, all theseduties andresponsibilitiesmayhaveseemedclear.Inpractice,however,thesystemprovedunworkable.

At 3:42 p.m., Tokyo Electric Power Company declared a “first level”emergency, a legal threshold meaning that an accident is predicted or hasoccurred.By law,TEPCOhad tonotify theheadof theMinistryofEconomy,Trade and Industry alongwith the governor of Fukushima Prefecture and themayorsofthetownsofOkumaandFutaba,thecommunitiesinwhichtheplantis located. The procedural requirements were clearly spelled out. Thenotification,accordingtotheplant’semergencyplan,wastobedonebysendinga fax “all at once, within fifteen minutes.” (Plant managers were advised tofollowupbyphone.)

But the emergency plan didn’t fit this emergency. There was no power.Phonelinesandcellulartowersweredamagedordestroyed.Faxesorphonecallswould be difficult, if not impossible. No one apparently had thought that anevent fierce enough to damage a reactor might also disrupt basiccommunications.

InsideFukushimaDaiichi’semergencyresponsecenter,ageneratorpoweredavideolinktoTEPCOheadquarters.Butcommunicationswithintheplantitselfweredifficult.Thepagingsystemwasdisabled;TEPCOhadprovidedonlyone-hour batteries for someof themobile units and therewas noway to rechargethem. Crew members often had to return to the emergency center to reportsimple details—a time-consuming and risky procedure. In many respects, theemergency communication system at Fukushima Daiichi reflected theunderlying premise of the plant’s comprehensive accident management plan,whichread:“Thepossibilityofasevereaccidentoccurringissosmallthatfroman engineering standpoint, it is practically unthinkable.” The follies resultingfromthiscomplacentattitudebegantobuildcatastrophically.

Under the provisions of Japan’s Act on Special Measures ConcerningNuclearEmergencyPreparedness,regulatorsfromNISAweretostaffanoff-sitecommand post and help coordinate the emergency response. At FukushimaDaiichi, thedesignatedcenterwas locatedabout threemiles from the reactors.When three NISA workers arrived there, they discovered no power, phoneservice,food,water,orfuel;additionalstaffcouldn’treachthefacilitybecauseofdamagetoroadsandmassivetrafficjams.Equallyproblematic, thebuildingwas not equippedwith air filters to protect those inside in case of a radiationrelease. (The lack of filters had been cited two years earlier by governmentinspectors, but NISA had failed to install them.) It seemed nobody ingovernment imagined a nuclear accident could produce a cloud of radiationintenseenoughtoposeahazardafewmilesaway.

BackinTokyo,thingswerenotgoingmuchbetter.Kanwasinthesituationroomwith his close advisors, few of whom knewmuch about nuclear powerplants.Cellphonesdidn’tworkinthebasement,makingcontactwiththeoutsideworlddifficult.Fivefloorsabove,thegovernment’snuclearexpertshadgatheredin another emergency response center. Some senior managers from TEPCOjoined them. But the two groups were not communicating with each other,despitebeinginthesamebuilding.NordidanyonefromthegovernmentheadtoTEPCO to ascertainwhat theutilitywasdoing. Inmany respects, governmentofficialswerefunctioningmuchliketheoperatorsinthecontrolrooms:withoutinformationtoguidethem.

Under normal circumstances, the reactor operators at Fukushima Daiichi hadaccesstoawiderangeofinformationaboutthestatusofcriticalsystemsviatheSafety Parameter Display System for each unit. But when the control roomsweredisabledbythelossofelectricalpower,thesteadyflowofinformationhadlargelyceased.

At3:50p.m.,someoneinthesharedcontrolroomforUnits1and2wroteonawhiteboard about their reactor cores: “Water levels unknown.”WithoutDCpower,operatorscouldnolongermonitorormanipulatetheisolationcondensersatUnit1ortheRCICatUnit2remotelyfromthecontrolroom.Evenworse,ifthose systems were not working and water levels dropped significantly,operatorscouldnotstartuptheemergencycorecoolingsystemsateitherunittopumpwaterintothereactorsquickly.ThingsappearedtobealittlebetteratUnit3. There, control room operators still had some backup battery power thatprovided readings on pressure and water levels and enabled them to operatesteam-drivencoolingsystems.Atabout4:00p.m., theywereabletorestart theRCICsystemandaddwatertokeepthefuelrodsintheUnit3corecovered.

Units 3 and 4 also shared a control room. With Unit 4 shut down formaintenance, that team focused primarily onUnit 3.The team’s colleagues intheUnits1and2controlroomhadtheirhandsfullwithbothreactors,althoughearly on Unit 2 seemed to pose a greater threat because operators could notconfirmwhethertheRCICwasoperatingormeasurethewaterlevelinthecore.In contrast, the operators believed the isolation condensers in Unit 1 wereworking,buttheycouldnotconfirmthiseither.

Tooperate the instruments that could provide the information they neededmost—the water, temperature, and pressure levels inside the reactors—theengineersatFukushimaDaiichibadlyneededpower.Theythoughttheyhadone

backup source left: emergency batteries. Soonworkers would be roaming themuck-anddebris-ladenplantgrounds,scavengingbatteriesfromundamagedcarsandbusesinadesperateattempttojury-rigsomesortofpowersystem.

But hooking up the batteries was a challenging task. With much of theplant’s electrical infrastructuredamagedordestroyed, crews sometimeshad tosearch for working connections behind control room panels or find circuitryelsewhere.Darknessandthepresenceofstandingwatermadethisadelicateanddifficult task.Batterieswere scarceand toosmall toprovideadequatevoltage.The few hours’ cushion the operators thought they might get was fastdisappearing.

At4:30p.m.,TEPCOissuedapressreleaseannouncingthat“abigearthquake”hadoccurredat2:46p.m.Morethan4millionhouseholdswerewithoutpower.“Duetotheearthquake,ourpowerfacilitieshavehugedamages,soweareafraidthat power supply tonightwould run short.We strongly ask our customers toconserveelectricity.”

TheapologeticpressreleaseincludedareassuringstatusreportonTEPCO’svarious generating stations in the affected area, including the company’sseventeennuclearreactors:sixatFukushimaDaiichi,fouratnearbyFukushimaDaini,7andsevenatKashiwazaki-Kariwa,locatedonthewesterncoastofJapan.“Atpresent,noradiationleakshavebeenconfirmed,”thereleasenoted.

But at FukushimaDaiichi and the utility’s command center in Tokyo, thetone was far less confident. At 4:46 p.m., exactly two hours after the firsttremors had been detected, TEPCOofficially notified the government that theemergencywasworsening.OperatorscouldnotdeterminethewaterlevelinthereactorcoresofUnits1and2andhadnoassurancethat thesystemstosupplyadditionalwaterwereworking.Specifically, emergencycorecoolinghadbeenlost at Units 1 and 2. This, under law, required the declaration of a “secondlevel”emergency.

The highest priority for the harried team in the darkened Units 1 and 2control room became restoring water-level indicators. At least then teammembersmighthaveabetterideaofthestatusofthetwounits.Theysalvagedtwo twelve-volt batteries from buses and additional batteries and electricalcablesfromacontractor’son-siteoffice.

Forafewtantalizingmoments,awater-levelgaugereturnedtolife,showingthat the levelwasdropping inside theUnit1 reactorvessel.Minutes later, the

gaugedied.Butthisfleetingindicationpointedtothepossibilitythatsoonwaterwould have to be injected from outside the reactor using portable pumps. Adiesel-poweredfirepumpwasstartedandallowedtoidle,readytoinjectwaterintotheUnit1reactorthroughaportalnormallyintendedforuseinfirefighting,notcorecooling.Inadditiontoadiesel-drivenfirepumpateachreactor, therewere three fire engines at Fukushima Daiichi that potentially could be used.TEPCOhadorderedfireenginesdeployedtoallitsreactorsitesafterafirebrokeoutat theKashiwazaki-Kariwaplant followinganearthquake in2007.But theutility did not contemplate that the fire engines might have to be used forsomethingotherthanfirefighting.

Unfortunately, as the plant operators knew, trying to get water into thereactorusingeither thefirepumpor thefireengineswouldnotbeeasy.Thesesources could supplywater only at a relatively low pressure compared to thepressure within the overheating reactor vessel. Unless operators coulddepressurizethevessel,theywouldn’tbeabletoforcewaterintoit.

As pressure increased inside the reactor vessel, steam flowed out throughsafety relief valves designed to keep the vessel from rupturing. Pipes leadinginto the torus carried the steamdownward. If the pressure suppression systemhadbeenworkingproperly,thesteamwouldhavebeencooledandturnedbackinto water in the torus, which would reduce pressure throughout thecontainment.Tokeepthetorusitselffromoverheating,itswaterwouldberoutedthrough tubes into heat exchangers, where seawater flowing around the tubeswouldabsorbtheheatandcarryitawaytothePacific.Butbecausetheseawaterpumps were destroyed, there was no effective way to remove heat from thetorus.

With no access to the Pacific and no electrical power, therewas only onewayleft toreducethepressurewithinthecontainment:byventingsomeofthesteam into the atmosphere. Thatwouldmake it easier to injectwater into thereactorandwouldlowerthelikelihoodofacontainmentbreach.Fortunately,theMarkIboilingwater reactorwasequippedwithanemergencyvent that,whenopened from the control room, would release steam into the environmentthrough a three-hundred-foot-tall stack. As part of the response to a safetyreviewthattookplaceafterthe1986Chernobylnuclearplantaccident,TEPCOhadtakenmeasuresinthe1990stoimprovetheeffectivenessoftheventsystem.

OnescenarioTEPCOhadnotanticipated,however,wasthattheventmightbeneededduringastationblackout,when thevalves required toopen itcouldnotbeoperated remotely from thecontrol room.Consequently, theemergency

guide did not explain how to operate the valves manually. Nor was the ventequippedwithfilterstoremoveradiationfromthesteamifanemergencyreleasewasrequired.Thedesignersofboilingwater reactorsbelieved that filterswereunnecessarybecauseradioactivesteamwouldbenaturallyscrubbedbywaterinthe torus before being vented. But this filtering mechanism had never beendemonstrated under real-world conditions, and some experts doubted itseffectiveness.

Theseweretwomoreholesinanemergencyplanthatwasturningouttobefullofthem.“Whenon-siteworkersreferredtothesevereaccidentmanual,theanswerstheywerelookingforweresimplynotthere,”investigatorswouldlaterwrite. “[T]hey were thrown into the middle of a crisis without the benefit oftrainingorinstructions.”

Nobodywassureiftheabilitytorelievetherapidbuildupofpressureinsideareactorwaswithinreach.InaBWRaccident,venting—acontrolledreleaseofradioactivity—isalast-ditchmovetostaveoffafarworsedisaster:coremeltingand failure of the containment, which could result in larger, uncontrolledreleases of radioactivity. The amount of radiation released during ventingdepends on the extent to which the core has been damaged. If it is badlydamaged, radiation levels in the steam could be deadly.At this point, no oneknewthestatusof theUnit1core,sotherelativerisksandbenefitsofventingwerenot clear.But guidedby scant data and instinct, the engineers knew thatsome sort of intervention to stabilize the reactor was needed—and neededquickly.Theymovedontwofronts:tobringinadditionalwatersuppliesandtoprepare,somehow,tovent.

Venting,inadditiontobeingtechnicallydifficult,wasfraughtwithpoliticalandpublic relations implications; as a result, both TEPCO management and thegovernmentinTokyowoulddemandasay.Ultimately,however,thedecisiontoventrestedwiththemostseniorofficialonthescene.AtFukushimaDaiichithatwasMasaoYoshida, fifty-sixyearsold,whohadbecome theboss tenmonthsearlier.

ThesuperintendentofFukushimaDaiichi,MasaoYoshida.TokyoElectricPowerCompany

Like a ship’s captain, the site superintendent knows the equipmentintimately, has firsthand knowledge of the unfolding crisis, and is bestpositionedtoassesstheoptions.UnderTEPCO’semergencyplan,Yoshidawastomake the callswith input fromutility executives.At themoment, however,TEPCO’stopexecutivesweremissinginaction.

Chairman Tsunehisa Katsumata was in Beijing on a business trip withJapanesemediaowners.PresidentMasatakaShimizuhadbeensightseeingwithhiswifeinwesternJapan.Shimizuhadreceivedanearthquakealertonhiscellphone,buthisefforts to return toTokyo thatafternoonwere thwarted.Hehadtraveledonlypartway,hopingtomakethefinallegofthetriphomeinaTEPCOhelicopter. But Japan’s civil aviation law bars private helicopters from flyingafter7:00p.m.Lateintheevening,hewonapprovalfromthegovernmenttoflyaboardaJapanAirSelf-DefenseForce(SDF)airplane,but,twentyminutesafterthe 11:30 p.m. takeoff, the defense minister (unaware of the officialauthorization)orderedtheplanetoturnaroundandinsteadstandbyfordisasterreliefduties.Shimizuwasleftonthetarmac.Itwouldbe10:00a.m.thenextdaybeforeheandKatsumatamadeitbacktoTEPCOheadquarters.

EvenifTEPCO’sexecutiveshadbeenonhand,thedecisiontoventwasn’tsolelytheutility’stomake.Governmentapprovalisnotrequiredbylaw,butitwas widely understood at TEPCO that government officials from severalagenciesneededtobebroughtintotheloop.AlthoughnooneknewexactlywhatwastakingplaceinsideFukushimaDaiichi,everybodywantedasay.Asaresult,thedecision-makingprocessaboutventingUnit1cametoanearstandstill.

Forthenuclearpowerestablishment, thedecisiontoventradioactivesteamholds serious implications. Releasing radiation into the environmentdemonstratesunequivocallytothepublicthatthisformofgeneratingelectricityis not as clean and safe as the industry’s public reassurances and promotionalcampaignsproclaim.

By lateafternoon,conditionsappearedseriousenough that Japanese regulatorsdecidedtonotifyinternationalauthorities.Shortlyafter4:45p.m.,NISAalertedthe International Atomic Energy Agency (IAEA) in Vienna that FukushimaDaiichihadreachedthestateof“nearaccidentatanuclearpowerplantwithnosafety provisions remaining.” Under the IAEA’s seven-level scale of nuclearaccidents,sevenbeingthemostserious,thatconstitutedalevel3event.

PrimeMinisterKanputoffdeclaringanuclearemergency,despitearequestthathedosoby theheadsofbothNISAandMETI.TheeventsatFukushimaDaiichiweren’twaiting,however.Justbefore6:00p.m.,aworkcrewwassenttothe fourth floorof theUnit1 reactorbuilding,hoping to learnmore about thestatus of the isolation condenser. They wore no protective clothing. As theyarrivedatthedoubledoorsofthereactorbuilding,theirdosimetersshotoffthescale,andtheyhurriedbacktothecontrolroom.ThisstronglyindicatedthattheUnit 1 core was now exposed and fuel rods had already ruptured. Full-scalemeltingofthecorewouldsoonbegin.

But theofficialword fromTEPCOwasvagueandoutdated.At5:50p.m.,the utility issued a press release announcing the “malfunction” of the dieselgeneratorsandtheresultinglossofbackuppowermorethantwohoursearlier.“There have been no confirmed radioactivity impact to [the] externalenvironment,”theEnglish-languageversionoftheannouncementsaid.“Furtherdetailsareintheprocessofbeingconfirmed.”

AcrossJapan,thescopeofthenaturaldisasterthathadhittheTohokucoastwasstill sinking in.More thanonehundred thousandmembersof theSelf-DefenseForces, the Japanese equivalent of the National Guard, had mobilized; localdisasteragencieswerestrugglingtograspwheretofocustheirattention;insomecommunities,wholeneighborhoodshadsimplyvanished,theirresidentswashedout to sea. Inplaces along the coast, tsunami survivorswere still trappedatopbuildingswheretheyhadfledtheoncomingwater.Itwascoldanddarknesswasfalling.Thehumantollwasstaggering.AsKanwouldlatersay,“Thefocuswasonsavinglives.”

Japan’sprimeministerNaotoKanannouncestheemergencyresponseeffortsonMarch11.Afterdeclaringthatthenuclearpowerplantsintheregionhadautomaticallyshutdown,hesaid,“Atpresent,wehavenoreportsofanyradioactivematerials...affectingthesurroundingareas.”CabinetSecretariat,GovernmentofJapan

Thatrescueefforttookonanaddeddimensionshortlyafter7:00p.m.,whenKandeclaredthenuclearemergencyrequestedtwohoursearlier.At7:45,chiefcabinet secretary Yukio Edano alerted the nation and the world that anemergencyhadbeendeclared.“Letmerepeatthatthereisnoradiationleak,norwill there be a leak,” Edano said in a reassuring voice. The primeminister’soffice apparentlywasunawareof thehigh readings taken earlier at theUnit 1reactorbuilding.Thatnewscertainlywasn’tcomingfromTEPCO.At9:00p.m.,thecompanyissuedanotherpressreleasewarningofapossiblepowershortage.

Shortly afterward,Yoshida gotwhat he thoughtwas a reprieve: thewatergauge onUnit 1 suddenly startedworking, indicating thewater levelwas stillalmosteight inchesabove the topof the fuel. (Inall likelihood, thegaugewasproviding an inaccurate reading because it was not calibrated for extremeconditions.)Notlongafterreceivingthatbitofapparentgoodnews,however,hegot the bad news. The radiation levels inside the Unit 1 reactor building hadrisen so high that entrywas forbidden, seriously complicating any emergencyrepairs.The radiation readingswerepositiveproof that the fuel corenowwasexposed andmost likelymelting. That findingwas passed on to Tokyo alongwithYoshida’salarmingpredictionthattheUnit2waterlevelandRCICstatuswereunknownandthatthefueltherecouldalsobeuncoveredsoon.

By then, authorities had ordered the emergency evacuation of those living

withinaboutatwo-mile(three-kilometer)radiusofthereactors.OfficialsofthetownsofOkumaandFutabadispatchedsoundtrucksandlocalfirefighterstogodoor-to-door with the announcement.Many of the residents were still reelingfrom the earthquake and tsunami, searching for missing loved ones, orscavenging for their possessions. Theywere told to leave immediately. Thoseliving a little farther out, between two and sixmiles (three to ten kilometers)fromthereactor,weredirectedtostayindoors.AlltheyweretoldwasthattherewereproblemsatFukushimaDaiichi.

Aspeoplefled,thefirstofaboutadozenpowersupplytruckswererumblingtowardFukushimaDaiichi,dispatchedthatafternoonfromTEPCOheadquartersandfromotherutilities.Thesemobilegeneratingunitsmightprovidethepowerso desperately needed. But the challenge of even getting to the plant wasenormous.Thedriverswereforcedtonavigateroadwaysbatteredbythenaturaldisasterandcloggedwithtrafficleavingthearea.By11:00p.m.thefirsttruckshadmadeit,andworkersattemptedtoconnectthegeneratorsbuthaddifficultylocating functioningelectricalpowerpanels.Unfortunately, someof thecableswere too short and the plugs incompatible.8 False alarms of another tsunamiinterruptedthetask,forcingworkerstofleetohigherground.Aftertwenty-fourhours,onlyonegeneratorwasoperating.

Duringthefirsthoursoftheaccident,ascrewsatFukushimaDaiichiscrambled,government andutility officials inTokyo lacked a similar senseof urgency, aresponse some later attributed to a failure of leaders there to understandwhatwashappeningattheplant.Theyseemedtofeelthattherewasadequatetimetodecide a course of action. PrimeMinisterKan, however, became increasinglyfrustratedthattheventingwasnothappening.

The delay in venting was the result of a number of factors. One was thedifficultyof theemergencyevacuation.Therewasan informalagreementwiththegovernmentofFukushimaPrefecturethatuntilnearbyresidentsweresafelyrelocated, ventingwould not occur. But even ifworkers had tried to start theventing immediately, theywould have had problems.Because the vent valvescouldnotbeoperatedfromthecontrolroom,theyhadtobeopenedmanually.Ittook hours to figure out where the valves were physically located and whichcouldbeopenedbyhand.

Bythe time theevacuationwasdeclaredcompleteand thedecision toventwas finally reached on themorning ofMarch 12, conditions at the plant had

worsened.Accessingandopeningtheventvalveslocateddeepinsidethedark,intensely hot, and now radioactive reactor buildingwas a farmore dangerousmission than itwouldhavebeen thepreviousevening.Thiswasa scenarionoaccidentdrillhadcovered.

In Tokyo, Kan’s irritation over the slow flow of information—and itsaccuracy—was mounting. In addition to the two hundred TEPCO technicaladvisorsondutyatcompanyheadquarters, fourhundredplantpersonnelunderYoshida’s direction manned Fukushima Daiichi’s emergency response center.CommunicationbetweenheadquartersandtheresponsecenterwasoccurringviaTEPCO’sin-housevideoconferencingsystem.

Thegovernment,on theotherhand,hadno similar ability to communicatewiththeplant.InTokyo,NISAobtainedinformationfromphoneconversationswithTEPCO.(AvideoconferencingsystemwasnotsetupuntilMarch31,whenthegovernmentandTEPCOcreateda joint responsecenter.)Dissatisfied,KanandhisadvisorsaskedTEPCOtoassignstaffmemberstotheprimeminister’soffice for briefings, and Kan and his aides eventually even began callingYoshida for answers, an action for which Kan would be later accused ofmicromanaging.

JustbeforemidnightonMarch12,theplant’semergencyteamwasabletogetapressurereadingoftheUnit1drywellusingaportablegeneratorinthecontrolroom.Theteamfoundthatitexceededthedesignmaximumoperatingpressure.At12:49a.m.onMarch12,YoshidadecidedthepressureinUnit1waslikelysohigh that venting now must take place. TEPCO president Shimizu, who stillhadn’t returned fromhisvacation, agreedwith thedecisionat about1:30 a.m.But TEPCO also wanted the government’s blessing. At this point, anunansweredquestionwaswhetherTEPCOmighthavetoventUnit2aswellasUnit1.

Unit1wastheonlyreactorofthesixthatreliedonisolationcondensersforemergency cooling. Apparently, even the shift team assigned to Unit 1 wasunfamiliarwiththatdesign.Hadteammembersbeentrainedinthesystem,theywould have recognized that it was not operating and that Unit 1 had beendeprivedofwaterforhours.

Meanwhile, the situation atUnit 2 also remained amystery.Although theRCICsystemhadstartedupatthetimeoftheearthquake,onceDCpowertothecontrol panelswas lost no one could tell whether the RCIC had continued tosuccessfullyinjectwaterintoUnit2.Yoshidafearedithadn’tandthatthetopof

thefuelwasabouttobeexposed.A crew wearing breathing gear and protective clothing ventured into the

RCICroominthebasementoftheUnit2reactorbuildingtodetermineitsstatus.Thefirsttripwasinconclusive.Asecondteamwasdispatched.ThiscrewsaiditbelievedtheRCICwasfunctioningbasedonpressuremeasurements.Withthatnews,Yoshida decided thatUnit 1warranted first priority;Unit 2 couldwait.Word was sent to Tokyo. Kan and Banri Kaieda, head of the Ministry ofEconomy,TradeandIndustry,agreed.

TEPCO managing director Akio Komori, who had once worked atFukushima Daiichi, joined Kaieda and the head of NISA at a joint pressconference shortly after 3:00 a.m. to announce the venting. If itwasmeant toprovidea reassuringmessage, it fell farshort. Justbefore thepressconferencebegan,thethreemenfoundtheyhaddifferinginformationaboutthestatusofthereactors.UncertainofwhatwasactuallyoccurringatUnits1and2,theydecidedthatKomoriwouldannounce theventingbutnot identify the reactor involved.When questioned by the media, he became confused. A few minutes later,government spokesman Yukio Edano took the podium to say that radiationwouldbereleasedbutthepublicshouldremaincalm.

Edanowas getting his information fromNISA,whichwas getting it fromTEPCO.When later asked to assess the accuracyof information coming fromhisofficetotheJapanesepublicatthistime,KanwouldsaythatNISAofficialswere“choosingtheirwordscarefully,”andasaresultEdanowasbeingmisled.

TheUnit1drywell,attwiceitsdesignpressure,waslikelyapproachingafailurepoint.Ventinghadtohappen,andithadtohappennow.Engineersattheplanthurriedly calculated possible radiation exposure from the release. As thepreparationscontinued,aworkerwassenttocheckradiationlevelsattheUnit1reactor building.Whenhe opened the door, he saw “white smoke” inside andquickly left without taking a reading. The smoke, whatever it was, clearlyshowed that somethingwas leaking somewhere.At about 4:00 a.m., radiationlevels near the plant’s main gate were measured at 0.0069 millirem (0.069microsieverts)perhour.Twentyminuteslater,theyhadjumpednearlytenfoldto0.059 millirem (0.59 microsieverts) per hour. The Unit 1 drywell was nowventingitself.

RADIATIONANDTHEBODY:DOSES,DAMAGE,ANDDEBATE

Radioactivematerials emit ionizing radiation—that is, radiationenergeticenoughtodetachelectronsfromatoms,turningthemintochargedparticles(called ions).Exposure to ionizingradiationcanhavedifferenteffectsonthe human body, depending on the extent and nature of the damage itcausesonthecellularlevel.

The relative biological damage in the human body resulting fromradiationexposureismeasuredinunitscalledsieverts.TheUnitedStates,unlikemostoftherestoftheworld,usesarem(“radiationexposureman”)asitsstandardmeasure.Onesievertisequivalentto100rem.

Oneclassofradiationeffectsisknownas“deterministic,”meaningthatacertainlevelofexposurewillalmostalwayscauseaparticularoutcome.Deterministiceffectsgenerallyresultfromlevelsofradiationhighenoughtokillcells,causingwidespreaddamagetotissuesororgans.Dependingonthe nature of the injury, such doses range from tens to hundreds of remdelivered over a short period. The resulting injuries include burns,cataracts, thyroid nodules, hair loss, gastrointestinal distress, low bloodcounts, and cardiovascular disease. Recent studies have also identifiedstatistically significant excess risks of certain circulatory diseases at lowdoses.These studies suggest that themortality fromsuchdiseasesdue tolow-doseradiationexposuremaybecomparabletothatfromcancer.

As the dose increases or wider areas of the body are exposed, thevictim may develop an illness known as “acute radiation syndrome.”Althoughthissometimescanbecuredwith treatment,highenoughdoses—above several hundred rem delivered in a brief period—will almostcertainly result in deathwithin days or weeks. Following the Chernobylaccident, twenty-eight people—plant workers and firemen in closeproximitytothedamagedreactor—areknowntohavediedinthismanner.Death from acute radiation syndrome would be classified as an “earlyfatality,” occurring within a few weeks or months after exposure to anuclearplantrelease.

Deterministic effects feature a dose “threshold” below which aparticulareffectwillnotoccur.Thisisbecausecellsmustsustainacertainamount of damage before the cell dies. In addition, a certain number ofcellsmustbeaffectedbeforeenoughtissuedamageoccurstocauseclinicalsymptoms.

Theothermajorclassofradiationeffectsisknownas“stochastic,”orrandom. Ionizing radiation can cause DNA damage thatmight producechangesincellularbehaviorleadingtocancer,butdoesnotdefinitelycausesuch changes. Cancer risk does rise with increasing doses, however,becausethemoreDNAlesionsthereare,thehigherthechancethatoneofthemwillleadtocancer.

It is currently estimated, based on studies of survivors of the atomicbombingsatHiroshimaandNagasaki, thatadoseof tenremdeliveredatonce will raise an individual’s lifetime risk of fatal cancer by about 1percent on average. This risk is higher for children and other groups ofpeople (for instance, thosewith certain genetic variations)who aremoresensitivetotheeffectsofradiationthantheaverageadult.Dosesdeliveredover lengthyperiodsmaybe lesseffectiveatcausingcancer,but there ismuch uncertainty about whether this is true. Because most cancers takemanyyears,evendecades,toappearafterexposuretoradiation,deathsduetostochasticeffectsarecalled“latentcancerfatalities.”

Increasesincancerriskassociatedwithlowdosesofradiationaresmallcompared to the background level of cancer in humans. Thus, inepidemiological studies it is hard to detect a direct cause-and-effectrelationship between radiation in the low-dose range (generally belowabout five rem) and cancer.However, there is broad scientific consensusthatallradiationexposure,nomatterhowsmall,producessomeincreasedrisk of cancer. It is biologically plausible that even a single particle ofionizingradiationcouldcauseenoughdamageinacelltoinducecancer.

Nonetheless, a small and vocal group, including some scientists,believesthattheabsenceofobservableevidenceforanincreaseincancerrisk at low doses implies that ionizing radiation is harmless below somethreshold.Thelogicisthatatthesedoses,therateofdamageissolowthatDNArepairmechanismscancombatitsuccessfully.Someevenbelieveinthe theory of “hormesis,” which holds that low doses of radiation areactuallybeneficialandcanstimulatetheimmunesystemlikeavaccine.

Althoughtheseargumentshavebeenreviewedandlargelyrejectedbyauthoritativescientificbodies,suchastheNationalAcademyofSciences’BiologicalEffectsofIonizingRadiation(BEIR)VIICommittee,advocatesofa thresholdcontinue tocite themas justification for thebelief that theharmfuleffectsofradiationingeneral,andnuclearenergyinparticular,areexaggerated.

At the extremes of pressure and temperature that the drywell was nowexperiencing, the bolts and seals used tomake it leak-tight were giving way,allowingradioactivesteamandhydrogengastoescapedirectlyintothereactorbuilding.Thiswasthelastbarrierpreventingthereleaseofradioactivityintotheatmosphere.Atleastthepressureinsidethecontainmentwasdropping,althoughnot enough to obviate the need for operator-controlled venting. The plantoperators needed to reduce the containment pressure by venting through thetorusinsteadofthedrywell; thensomeoftheradioactivitymightbefilteredasthegasespassedthroughwater.Otherwise,unfilteredreleasesdirectlyfromthedrywellwouldcontinue.

To vent the Unit 1 containment, workers needed to manually open twovalves in different locations. The first was on the second floor of the reactorbuilding.Without electric power, workers would have to open it with a handcrank—provided they could reach it. The second valve was in the basementtorus room.Ordinarily thebasement valve required compressed air to operate.Byporingoverplantdrawings,however,workershadlocatedawheelhandleonthevalvethattheycouldusetoopenitmanually.

They now mapped out the route they would take to get to it. Their pathwouldbe through thedarkandhot reactorbuilding. In thepast fewhours, theplant site had been rattled by twenty-one aftershocks, raising fears of anothertsunami.Whatifanotherwallofwaterweretosweepinandsurroundthemall?

But the more immediate threat was invisible: the rising radiation level.Crewsnowhadtowearprotectivegearandbreathingequipmentiftheyventuredoutoftheemergencyresponsecenter.Soon,radiationlevelsroseeveninsidetheUnits1and2controlroom,andoperatorstherehadtowearfullfacemasksandprotectiveclothing.MostofthecontrolroomteammovedtotheUnit2sideoftheroomandcroucheddownonthefloor,wheretheradiationwasalittlelower,todotheirwork.

Workerswearing protective clothing and respirators inside theUnit 2 control roomonMarch 26, 2011,afterpowerisrestoredattheplant.TokyoElectricPowerCompany

Meanwhile, workers continued their efforts to force water into the Unit 1corebyanymeansavailable.Thediesel-drivenfirepumpidledforhours,butitremaineduselessbecauseoperatorscouldnotdepressurizethereactorvesselandthepumpwasnotpowerfulenoughtoinjectanywaterintoit.Finally,thepumpshutdownandcouldnotberestarted.

And then, an apparent miracle happened, but it was a mixed blessing. Ataround 2:00 a.m., operators were able to recover some instrumentation usingbatteries and discovered that the reactor vessel pressure had droppedsignificantlyallbyitself.Ononehand,thepressure,althoughstillhigh,wasnowlowenoughtogivethefireengineson-siteachanceofgettingwatertothecore.On the other hand, the depressurizationwas an ominous sign that the reactorvessel had sprung a leak somewhere—although it is not clear that anyoneappreciatedthatatthetime.

At about 4:00 a.m., workers finally managed to connect a fire hose to aportal on theUnit 1 turbine building, providing a pathway for one of the fireenginestopumpfreshwaterintothereactorcore.Ittookalmosttwomorehourstoestablishaconsistentflowrate,butfor thefirst timeinnearlyfifteenhours,waterwasreachingthecore.However,itwastoolittle,toolate.Thefireenginepumppressurewasstilltoolowtoforcemuchwaterintothevessel.Andinanyevent,itislikelythatbythenthecorehadalreadymeltedthroughthebottomofthereactorvesselanddroppedtothecontainmentfloor.Ifso,muchofthewaterbeinginjectedintothecorewasprobablyflowingoutintothecontainment.

Thewhole exercise had takenmuch longer than anyonehad anticipated inpartbecausenoplantworkerknewhowtooperate the fireenginesmaintained

foremergenciesatthereactorsite.Acontractorhadtobeconvincedtohelpwiththearduoustask.Withrisingradiationlevels,ongoingaftershocks,andthethreatofanothertsunami,thecontractorwasreluctanttoagree.

InTokyo,atboththeutilityandtheprimeminister’soffice,everyonewasaskingthesamequestions:Whenwastheventinggoingtobegin?Whywasittakingsolong?WhenPrimeMinisterKanaskedtheTEPCOofficialassignedtohisofficetoexplainthedelay,theonlyanswerhegotwas:“Idon’tknowthereason.”

Shortlyafter6:00a.m.,Kandecidedtofindoutforhimself.Inthemidstofthe growing crisis at the plant,Yoshidawas informed that the primeministerwas en route via helicopter. Before Kan left Tokyo, he ordered authorities towiden the evacuation zone around the plant from about two miles (threekilometers)tosixmiles(tenkilometers).Withoutcarefulcoordination,however,thatwould put a lot of people on the roadswhen the venting finally did takeplace. Nonetheless, while Kan was airborne, METI minister Banri KaiedaorderedTEPCOtovent.

At7:11a.m.,Kan,accompaniedbyHarukiMadarame, thechairmanof theNuclear Safety Commission, landed at FukushimaDaiichi. Yoshida explainedthe difficulties to Kan, who calmed a bit when he discovered that he andYoshidahadattendedthesamecollege,theTokyoInstituteofTechnology.Kanrepeated the order: vent. Yoshida promised that would happen by about 9:00a.m.Fiftyminutesafterhearrived,KanheadedbacktoTokyoandYoshidabackto managing the disaster. Although Kan’s dramatic fly-in garnered muchpublicity (and eventuallywasportrayedbyhis critics asdangerousmeddling),Yoshidaremainedthemancallingtheshots.

Threetwo-personteamssuitedupwithprotectiveclothing.Theywereabouttoenteradark,highlyradioactivereactorbuildingthattheymighthavetofleeatany moment because of the intermittent earthquake tremors. They knew theywouldhavejustafewmomentstoaccomplishtheirtaskbeforetheywouldreachtheir allowable radiation dose and have to retreat. The makeup of the teamsreflected the radiation exposure risks everybody recognized: young employeeswereexcludedfromthemission.

At 9:02 a.m., the plant was notified that the evacuation of residents wascomplete and that the venting could now begin. (The information about theevacuationturnedouttobeincorrect.)ThefirstteamenteredthesecondflooroftheUnit1 reactorbuilding, flashlightsproviding theonly illuminationas teammemberssearchedforandlocatedthehandcrank.Withtoolsabout thesizeof

thoseusedtochangeacartire,theycrankedtheventvalveopenaquarterofthewaybeforetheyhastilyleft.Inthetenorsominutestheyhadbeeninside,eachman had received a radiation dose of two and a half rem (twenty-fivemillisieverts),one-fourthofthetotaldosetheywerepermittedtoreceiveunderemergency conditions for an entire year. When members of the second teamenteredthetorusroominthebasementofUnit1toopenthesecondvalve,theyfounddoseratessohighthattheywereunabletoreachit,andtheyfled.Evenso,oneoftheoperatorsexceededtheemergencydoselimitoftenrem(onehundredmillisieverts).Entryeffortswerethenabandoned.

A new plan was devised; it, too, proved problematic. There was another,largervalvethatmightbeopenedfromthecontrolroomwithbatterypoweranda compressed air supply. But the available compressor didn’t work withoutelectricity,andnobodyhadaportableunit.Onceagain,contractors’officesonandofftheplantsiteweresearched.Moretimeelapsed.

Workers then attempted to open the small air-operated valve in the torusroomfromthecontrolroominthehopethattherewasstillenoughresidualairinthevalvetomakeitwork.Forventingtobesuccessful,thisvalvewouldhavetoremain open long enough to create pressure in the vent sufficient to burst arupturedisk,whichservedasthelastbarrierbetweentheradioactivegasandtheenvironment. When radiation levels spiked at the main gate and at severalmonitoringpostsatabout10:40a.m.,operatorsthoughttheirventingattempthadworked and the disc had ruptured. However, soon afterward radiation levelsbegantofallanditwasnolongerclearthattherehadbeensignificantventing.

Finally, shortly after noon, a portable compressor was located and jury-riggedsoitcouldbeconnectedtothesystemthatnormallysuppliedairtoplantequipment.TogetherwithtemporaryDCpower,thisallowedoperatorstoopenthelargeair-operatedvalvefromtherelativesafetyofthecontrolroom.At2:00p.m., thecompressorwasstartedandthe largevalveopened.Pressuredroppedinside the containment, and presumably inside the reactor vessel as well,allowingoperatorstoinjectwateratahigherrate.

Another sign that the operators might have succeeded came when NHKcameras trained on the plant from a distance capturedwhite smoke emergingfromtheexhauststacksharedbyUnits1and2andrisinghighabovethesky-blue reactor building. Yoshida and the exhausted crew in the emergencyresponsecenterthoughttheyhadfinallycaughtabreak.At3:18p.m.,henotifiedTEPCOinTokyooftheventing.

CapturedbyanNHKcamerapositionedabouttwentymilesaway,theexplosioninsideUnit1at3:36p.m.onMarch12destroystheroofofthereactorbuildingandblowsoutapanelintheadjacentUnit2reactorbuilding.NHK

Yoshida had other progress to report aswell. Recognizing that freshwatersupplieswere limited, he had orderedworkers to come upwith amethod forutilizingseawatertocoolthereactors.Afterfreshwatersupplieswereexhaustedshortlybefore3:00p.m.,hegavetheordertopreparetousethePacific.Itwasacomplicated endeavor—workers had to position three fire engines withinterconnectinghosestopumpseawatertransferredintoapit—butby3:30p.m.,thelinestoinjectseawaterintotheUnit1reactorwerealmostinplace.Asteadysupplyofvitalcoolingwaterforthecorewasnowwithinreach.

Andthen,at3:36p.m.—almostexactlytwenty-fourhourssincethetsunamihad roared in and flooded the plant—apowerful explosion ripped through theUnit1reactorbuilding,blastingofftheroofandsendingdebriseverywhere.Theimpactblewout apanel in theneighboringUnit 2 reactorbuilding. Inside theemergency response center, stunned workers watched the explosion ontelevision,notsureexactlywhathadblownup.

2

MARCH12,2011:“THISMAYGETREALLYUGLY...”

At9:46a.m.onMarch11localtime,theU.S.NuclearRegulatoryCommissionofficiallyenteredwhatitcallsMonitoringMode,aheightenedstateofreadinesstorespondwhenanuclearincidentisunfolding.IthadbeenexactlyninehourssincetheearthquaketremorswerefirstdetectedatFukushimaDaiichi.

NRC personnel with a wide range of expertise assembled in the agency’sOperations Center, a low-ceilinged room crowded with desks and computermonitors.TheNRCiscurrentlyhousedinthreemodernmid-andhigh-riseofficebuildings in Rockville, Maryland, just outside Washington, DC. Theheadquarters complex is often simply calledWhiteFlint, after a nearbyMetrostop.

Overnight,newsmediahadbeguncarryingstoriesaboutthenaturaldisasterin Japan, where local time was fourteen hours ahead of Washington. Now,details aboutmounting problems at the FukushimaDaiichi reactors vied withaccountsaboutthedevastationfromtheearthquakeandtsunami.TheNRCstaffwasscramblingtolearnmore.

Earlierthatmorning,theNationalOceanicandAtmosphericAdministrationhadissuedatsunamiwarningfortheU.S.Pacificcoast,triggeringconcernabouta possible threat to the Diablo Canyon Power Station in California and othercoastal nuclear facilities. (When the wave did arrive at about 8:30 a.m. localtime, it amounted to a surge no larger than the normal tides; U.S. nuclearoperationswerenotaffected.)TheinformationavailablefromJapanatthattime,however, convinced NRC officials that the disaster there had now risen farbeyond anyWest Coast consequences. Responsibility shifted from theNRC’swesternregionalofficetoheadquarters.Ultimatelymorethanfourhundredstaff

membersatWhiteFlintandaroundthecountrywouldbedrawnin.

TheOperationsCenter at theNuclearRegulatoryCommission (NRC) headquarters outsideWashington,D.C.More than fourhundredNRCstaffmembersnationwidewere involved inanalyzing theaccidentatFukushimaDaiichi.U.S.NuclearRegulatoryCommission

Details were arriving from a variety of sources; most of the news wassecondhand.Japan’sAsahiShimbunwasreportingthatastateofemergencyhadbeendeclaredandevacuationswereplanned.CNNreportedthatradiationlevelswere increasing. On the other hand, Reuters quoted the World NuclearAssociation inLondon, an industry tradegroup, as stating that the situation inJapanwas“undercontrol.”

AmongNRCstaffmembersacrosstheagency,e-mailswereflyingfuriouslyas theycombed theWebandTVnetworks for information, sharing their findswitheachotherandstrugglingtoputthesometimesconflictingpiecestogether.Soon,however,thosepiecesappearedtoadduptoanominousaccident,astheire-mailsreveal:

9:21a.m.:“Wearesafeandluckythistime.”9:42a.m.:“[M]yunderstandingisthatthisisaStationBlackoutandifthey

don’tgetsomekindofpowerbackit’sonlyamatteroftimebeforecoredamage.Thisisareallybigdeal.”

More details were shared—and analyzed from a distance of nearly seventhousandmiles.Withinminutesof the earlymorningpressbriefings inTokyoannouncing plans to vent radiation, the implications of that decision wereobviousatWhiteFlint.

3:07p.m.:“Thismaygetreallyuglyinthenextfewdays.”

Evenas theystruggled tocomprehend the tollonhuman livesandpropertyofthenaturalcatastrophe thathadstruckJapan, themenandwomenof theNRCknew that the disaster unfolding inside the reactors half a world away hadimplicationsforWhiteFlint.ThefateofFukushimaDaiichicoulddramaticallyaffectthecommission’sownfuture,whichiscloselytiedtothefortunesofthenuclearindustry.

AmongthemessagescrisscrossingtheNRCasthecrisisdeepenedwasonethatputthisconcerninanutshell:

“Isthissafetybadoreconomicsbad?”askedane-mailsenttoBrianWagneroftheNRC’sOfficeofNewReactors.

“Both,”Wagnerreplied.

Likemany regulatory agencies, theNRCoccupiesuneasygroundbetween theneedtoguardpublicsafetyandthepressurefromtheindustryitregulatestogetoff its back. When push comes to shove in that balancing act, the nuclearindustryknowsitcancountonasympathetichearinginCongress;withmillionsofcustomers,thenation’snuclearutilitiesareaninfluentiallobbyinggroup.

Overtheyearssinceitsestablishmentin1974,theNRChasbeenaccusedbymanycriticsoffavoringtheindustry’spointofviewwhenitcomestoadoptinghigher safety standards. To the critics,when the questionwas “safety” versus“economics,” it seemed that economics often won. The NRC’s supportersresponded that nuclear power generation was already so safe that tighterrequirementswererarelyworththeircosttoindustry.

ThecrisisnowbeginninginJapanplainlyhadthepotential toundercut thesafety argument.What theNRC staffers could not yet knowwas how clearlyFukushima Daiichi would demonstrate the dangers that arise when regulatorsbecometooclosetotheindustrytheyoversee.

Japan is not the United States; the relationships between government andbusinessinthetwonationsareasdifferentasotheraspectsoftheircultures.ButthehistoryofnuclearpowerinJapan,andtheincestuouspracticesthatfosteredit,doprovidedramaticevidence thatgiving thenuclear industry thebenefitofthedoubtcanleadtounimaginablydireconsequences.

•••

At themomentanNRCstafferspeculated things“mayget reallyugly,” itwas5:07a.m.March12inJapan.InsidetheSeismicIsolationBuildingatFukushimaDaiichi, Masao Yoshida was struggling to figure out how to vent the Unit 1reactor.PrimeMinisterKan,frustratedwithalackofinformation,wasabouttohead to theplanthimself.And thousandsof Japaneseembarkedon the firstofwhatwould be a torturous series ofmigrations as they evacuated froma two-mileradiusaroundtheplant.

Thiswasn’tthefirsttimeJapanesecitizenshadhadtofleearunawaynuclearaccident.Norwasitthefirsttimetheyhadhadreasontoquestiontheresponseofnuclearauthorities.

InSeptember1999,insideanondescriptindustrialbuildinginTokaimura,avillage about seventy miles northeast of Tokyo, three employees of the JCOCompanywerepreparingasmallbatchof18.8-percent-enricheduraniumfuel—containingafarhigherconcentrationofuranium-235thanthetypicalfuelusedinpowerreactors—foruseinanexperimentalfastneutronreactor.Theworkerswereuntrainedinhandlingmaterialofthisenrichmentlevelandwerepreparingthefuelinstainlesssteelbuckets.Inahurry,theypouredthesolutionintoatank,bypassingsafetycontrols.Themixturewentcritical, initiatingaself-sustainingchainreactionthatcycledonandoffforhours,periodicallyemittinghighlevelsofgammaandneutronradiation.Theindustrialbuildingprovidedlittleradiationshieldingbecauseundernormalconditionstherewasnoneedforit.

Government response to the accident was slow, even as radiation spreadnearlyamileaway.AlmostthreehourselapsedbeforearadiologicalmonitoringteamfromthenationalScienceandTechnologyAgencywasdispatched to thescene; the teammembers initially did not believe there was much reason forconcern.Fivehoursafter the incidentbegan,about160 residentswereorderedout of their homes. Seven hours after that, about 310,000 peoplewere told tostayindoorsfortwenty-fourhours.Workerspiledsandbagsandothershieldingmaterials around the facility to reduce dose rates outside the fence. It tooktwentyhourstohaltthecriticality.Thethreeworkersattheplantwereseverelyoverexposed;twodied.

ReactiontowhatwasatthetimeJapan’sworstnuclearaccidentwasmuted.Two-thirds of Tokaimura residents surveyed said they were now critical ofnuclearpower.Butabouthalfsawtheirvillage’sfutureas“co-existingwiththenuclearindustry,”notsurprisingsinceathirdofthepopulaceworkedatoneofthe dozen or more nuclear facilities nearby. (This part of Japan is known as“nuclearalley.”)

Outside Japan, however, the events in Tokaimura and Tokyo’s responsecameunder sharpattack.Aweekafter theaccident, a scathingeditorial in theBritish journal Nature placed responsibility “squarely on the shoulders ofgovernment,” specifically, its Science and Technology Agency, “which isproving itself incapable of adequately regulating the safety of nuclear power.”(Agovernmentreorganizationin2001shiftedregulatoryresponsibilitytoanewbody, the Nuclear and Industrial Safety Agency, or NISA, which would beoverseenbytheNuclearSafetyCommission.)

“The Japanese government seems unable to set up competent regulatorybodieswith sufficient staff and expertise,” theNature editorial continued.TheNSC “is a group of part-time academic experts who rubber-stamp documentsproducedbyasmall teamofofficials,whoarefar toofewinnumberandlackthe expertise needed to regulate the safety of such a huge and potentiallydangerousindustry.

“Will the situation improve significantly after this accident? Based on therecordtodate,probablynot.”

Beforetheendof1999,JapaneselawmakerspassedtheNuclearEmergencyPreparedness Act, intended to improve cooperation among various levels ofgovernment in the event of an accident.The law also established an elaboratenotification and response framework. Sadly, however, Nature’s pessimisticassessmentwasonthemark.ThemodestreformsimplementedafterTokaimuradid not forestall the confusion and lack of preparedness that helpedmake theFukushimaaccidentsomuchworsethanithadtobe.

WhiletheColdWarhelpeddrivesupportforthenuclearindustryintheUnitedStates,theindustry’sprivilegedstatusinJapanhasmuchdeepereconomicroots.Japanisanationthatconsumeslargeamountsofenergybuthasfewresourcesofitsown;itcurrentlyimportsallbut16percentofitsenergyneeds.OnlyChina,theUnitedStates,India,andRussiaconsumemoreenergythanJapan,andtheyaremuchlargercountries.

Achievingenergyself-reliancehaslongbeenamajorpreoccupationfortheJapanese.As the nation struggled toward recovery afterWorldWar II, energysecurity became the lynchpin to its comeback. Power shortages during theKoreanWar, coupledwith soaring demand from industry and new residentialcustomers, led the Japanese government to step in with assistance for thecountry’sutilities,ofwhichTEPCO, theTokyoElectricPowerCompany,wastheoldestandlargest.“Throughdirectandindirectmeans,thepowercompanies

reaped enormous sums from Treasury coffers,” according to scholar Laura E.Hein. Once the utilities, which held regional monopolies, had improved theirsolvencyandinvestedinadditionalfossilandhydroplants,Japaneseauthoritiesturnedtheirattentiontowardatomicpower.

InJapan, radiationhasaheightenedsymbolism. In1945, theUnitedStatesdropped atomic bombs on Hiroshima and Nagasaki, resulting in an estimated140,000deathsand leading to Japan’s surrender inWorldWar II.Despite thisindelible legacy, the prospect of deriving abundant energy from the atomwastooenticingtoignore.OnMarch4,1954,theDietapprovedabudgetfornuclearenergydevelopment.

TheUnitedStates stood ready tohelp.ColdWar tensionswere increasing;theSovietUnionwasbecomingaglobalthreat,andtheUnitedStateswaseagertocementanallianceinthePacific.Washington’sAtomsforPeaceplanbecametheidealvehicle.TheEisenhoweradministrationandthosewhofavoredprivatenuclear development in the United States were looking for ways to promotepeacefulusesathomeandabroad.

In September 1954, Thomas E. Murray, a member of the U.S. AtomicEnergyCommission (AEC), delivered a speech to three thousandmembers oftheUnitedSteelworkersofAmerica.Histopicwasthedevelopmentofnuclearpower,buthewasjustasconcernedwithflagwaving.Optimismwasalreadyinthe air. Just five days earlier, Lewis L. Strauss, chairman of the AEC, haddelivered a similarly upbeat message to the National Association of ScienceWritersinwhichheutteredanoft-quoted(lateroft-derided)prediction:“Itisnottoomuchtoexpectthatourchildrenwillenjoyintheirhomeselectricalenergytoocheaptometer.”

Murray,inhisaddress,spokeeloquentlyaboutnuclearpowerandAmerica’sstature.Onewaytoassertandmaintainitsgloballeadership,hesaid,wasfortheUnitedStatestobuildanuclearreactorinJapanbeforetheSovietscould.

A reactor would be a “lasting monument to our technology and ourgoodwill,”Murraytoldtheunionmembers.“Becausetheeconomicsofnuclearpoweraresouncertain,itisunrealistictoexpectprivateindustrytoundertakeonapurelyriskbasisanythingliketheeffortthattheworldatomicpowerproblemdemands.” Shying away from nuclear power for cost reasons alone would be“inconsistentwithall thisnationstandsfor”andwould“playintothehandsoftheSoviets.”

This came as great news, certainly for the steelworkers, who would reapskilled manufacturing jobs, but also for U.S. companies like Westinghouse

Electric Corporation and GE, which already had a toehold in Japan. Thepreviousyear the twomanufacturershad loanedJapan$6.1million tohelp thegovernment purchase thermal generating equipment. Now, with the U.S.government proselytizing its benefits, they saw an opportunity tomarket theirnewest technology: nuclear energy. For the Japanese, the atom held out thepromiseoffinallyattainingasecureenergyfutureandfuelinggrowth.InAugust1956,constructionbeganonthecountry’sfirstnuclearfacility,aresearchcenter,inTokaimura.ThevillagesoonwouldalsobecomehometoJapan’sfirstnuclearreactor.

The appeal of nuclear power in Japan went beyond central governmentbureaucrats.Where plants were built, local economies benefited in ways thatstrengthenedthenuclearindustry’spoliticalaswellaseconomicclout.

In1958,thegovernorofFukushimaPrefectureapproachedTEPCO,hopingtopersuadetheutilitytobuilditsfirstreactorsalonganunderdevelopedstretchof coastline. Themotivewas purely economic.Rural areas of Japan, like thisregion and the Sanriku Coast to the north, were losing population to cities.Eventually,aportionofthecoastsharedbythetownsofFutabaandOkumawaschosenforthenewplant.

Local officials welcomed the project, but kept their negotiations withTEPCOsecret,fearingsomeresidentsmightnotbesoenthusiastic.TEPCO,forits part, dispatched young female employees to accompany utility engineersinspecting the proposed site, both disguised as vacationing hikers to avoidarousing public suspicions. Only two years after a deal was sealed did localresidentsfinallylearnoftheconstructionplans.

GroundwasbrokenforthefirstreactoratFukushimaDaiichiinJuly1967.TEPCOchoseGEasthecontractor,avendorithadusedforconventionalpowerplants.GEwouldbuildoneofitsnewdesigns,theMarkIboilingwaterreactor.(The first twoMark I reactors, atOysterCreek inNew Jersey andNineMilePointinNewYork,begangeneratingpowerin1969,whiletheFukushimaplantwas under construction.) TEPCO, which by 1970 was the world’s largestprivatelyownedutility,wouldstickwithGEdesignsforthefiveotherreactorseventually built at Fukushima Daiichi and for two of four units at nearbyFukushimaDaini.

Localofficials’predictionsthatthegiantFukushimaDaiichicomplexwoulddeliverafinancialbonanzaprovedtrue.Inanefforttopromotenuclearprojects,the national government provided subsidies to local governments. As the

reactorswereconstructedandcameonline,localpropertytaxrevenuessoared.By1978,thetownofOkumaderivednearly90percentofitstaxrevenuesfromthe plant, which also provided badly needed jobs. Residents enjoyed sportsfacilitiesandotheramenities.ManyotherreactorprojectswerelaunchedalongJapan’scoaststotakeadvantageofseawaterforremovingwasteheat.

Japan’s nuclear quest entwined government and private industry in a tightalliance.Thepushbybusiness leaders, politicians, academics, andbureaucratssteamrolledthefewexpertswhoraisedwarnings.Onesuchexpertwasayoungseismologist, Katsuhiko Ishibashi. A newly minted PhD from the prestigiousUniversity ofTokyo, Ishibashi discovered that a fault linewest ofTokyowasmuch larger than previously assumed. The Hamaoka nuclear power plant satatop that fault. Ishibashi’s research findingswerepublished in 1976, the sameyearHamaoka’sUnit1beganproducingelectricity.Bythen,Japanhadtwentyreactorsoperatingorunderconstruction.Notuntiltwoyearslater,in1978,didJapaneseauthoritiesdraftseismicguidelinesforreactordesign.

Finding an area in Japan not susceptible to seismic activity was difficult.Advancesinseismologywererevealingtheexistenceofheretoforeunidentifiedfaultsthathadproducedmassiveearthquakesinthepast,andmostlikelywouldproduce themin the future.Theembraceofnuclearpowerbygovernmentandindustry was not about to be slowed, however. Time and again, utilities andregulatorsdownplayedorignoredthethreatposedbyearthquakes.

For Ishibashi, the issue became a lifelong crusade. In 1997, he coined theterm genpatsu-shinsai, a catastrophe involving a quake-induced nuclearaccident. He envisioned a scenario in which there was a loss of power to areactor and “multiple defense systems lose their function simultaneously,”resultinginthereleaseofradiationoverawidearea.

MostmembersoftheJapanesepublicpaidlittleattentiontosuchwarnings;for them, the development of nuclear power went hand in hand with animproving economy. Japan boasts one of the most reliable electrical deliverysystemsintheworld.Its tenutilitiespromotedreactorsasawaytoensurethateconomicgrowth—andthelifestyleitprovided—wouldcontinue.

Not everyone was happy. In 2003, residents living near Hamaoka—which bynow had four operating reactors—sued to shut them down, arguing that theywereunsafeandcouldnotwithstandamajorearthquake.Testifyingonbehalfof

plant owner Chubu Electric was Haruki Madarame, a University of Tokyoprofessorandnuclearproponent,whowouldeventuallybeappointedchairmanofJapan’sNuclearSafetyCommission,apositionheheldonMarch11,2011.Madaramehadpublicly scoffedat thewarningsof Ishibashi and theHamaokaplaintiffs—including the possibility of a simultaneous failure of emergencygenerators—saying such concerns would “make it impossible to ever buildanything.” A court concluded that the safety measures at Hamaoka wereadequate.

Other lawsuits challenging reactor safety also met with defeat. In 1979,residentsintheareaofKashiwazaki,atowninNiigataPrefectureontheSeaofJapan, asked the courts to overturn a license granted toTEPCO to buildwhatwouldbecometheworld’slargestnuclearplant,withsevenreactors.Thelawsuitclaimed that thegovernmenthad failed toperformadequate inspectionsof thegeology of the plant site and had overlooked an active fault line. The lawsuitwound on for a quarter century, while the Kashiwazaki-Kariwa nuclear plantwas built andbeganoperating; then, in 2005, a court ruled therewas no faultline.Twoyearslater,amagnitude6.8quakestruckoffthecoasttenmilesfromKashiwazaki-Kariwa. A fire broke out at the plant, which was designed towithstandonlyquakesofmagnitude6.5orlower.

“What happened to the Kashiwazaki-Kariwa nuclear plant should not bedescribedas‘unexpected,’”IshibashiwroteintheInternationalHeraldTribuneshortlyafterward.ThiswasthethirdmajorearthquaketostrikenearaJapanesenuclear facility in two years. But as the plant suffered no significant damagefrom the quake, regulators remained confident that existing seismic standardswereadequate.

Other legal challenges on safety issues routinely failed. According to ananalysis by the New York Times after the 2011 earthquake, fourteen majorlawsuits raising reactor safety questions had been filed against the Japanesegovernment or utilities since the late 1970s. Evidence often revealed thatoperatorshaddownplayedseismichazards.Inonlytwoinstancesdidcourtsrulefor the plaintiffs, and those decisions were overturned by higher courts, theTimesreported.“IfJapanhadfaceduptothedangersearlier,”IshibashitoldtheTimes soon after the March 2011 disaster, “we could have preventedFukushima.”

That’snottosaytheJapaneseauthoritiessimplydismissedtheearthquakethreat.In1978,parliamentpassedtheLarge-ScaleEarthquakeCountermeasuresAct,a

lawbasedonthebeliefthatquakescouldbepredictedwellinadvance.The quest to forecast earthquakes is as old as the science of seismology

itself. “Ever since seismology has been studied, one of the chief aims of itsstudentshasbeentodiscoversomemeanswhichwouldenablethemtoforetellthe coming of an earthquake,” wrote JohnMilne in 1880. Milne, an Englishgeologist and mining engineer who became interested in earthquakes whileteaching in Japan, helped found the Seismological Society of Japan that sameyear.He is considered the father ofmodern seismology in part becauseof hisworkinthatcountry.

Accuratepredictions,however,haveremainedatantalizingbutelusivequest.“Journalists and the general public rush to any suggestion of earthquakeprediction like hogs toward a full trough,” said C.F. Richter, fromwhom thescalemeasuringearthquakes’energygotitsname,whenacceptingtheMedalofthe Seismological Society of America in 1977. “There is nothingwrongwithaiming toward prediction, if that is done with common sense, proper use ofcorrectinformation,andanunderstandingoftheinherentdifficulties.”

Richter’sadmonitionnotwithstanding,manycametobelievetheycouldnotonly predict earthquakes with accuracy but also determine which areas werelikelytobesafefromseriousdamageandthereforesuitablefornuclearreactorsandotherpotentiallyhazardousfacilities.

Debates over site suitability or the adequacy of standards ignored theinescapable fact thatnoonecouldclaim trueknowledgeof themassive forcesalwaysatworkfarbelowthetopographyofJapan.Nomatterhowrigorousthestandardsappliedtonuclearplantsitingandconstruction,therewouldalwaysbeuncertainty;anditwasn’tclearifsciencecouldsayhowlargethoseuncertaintiesactuallywere.

That reality didn’t deter the adherents of prediction or thosewho believedthat limited standards could ensurepublic safety.Among thosepromoting thisbeliefwerethenuclearindustryandthosechargedwithregulatingit.

Japan’s new seismic protection lawwas directed toward a single event: ashallowmagnitude 8.0 earthquake in the Tokai region, about sixty-two miles(one hundred kilometers) southwest of Tokyo. Seismologists such as KiyooMogiof theUniversityofTokyohadlongwarnedofadisastrousquakein thedenselypopulated region. (While the legislationwaspending,amagnitude7.0earthquake struck nearby, causing twenty-five deaths andwidespread propertydamage.)Theactsetupanetworkofmonitoringstationsintendedtogivethreedays’ advance warning. Soon, the public—and government—came to assume

thatthenextBigOneinJapanwouldhitTokai.Andthey’dgetplentyofnotice.Mogicautionedthattheunderlyingconceptofthelaw—thattherewouldbe

an unmistakable warning—was flawed. Earthquakes aren’t predictable in thesameway tides or sunsets are, hewrote in 2004; instead, scientistsmust basejudgments on complex data whose relation to seismic events is not fullyunderstood. Mogi was troubled that the government was so confident in itsabilitytopredictearthquakesthatitcontinuedtolicensenuclearplantsinanareaofhighrisk:namely,Hamaoka.

Japaneseofficialshadbeguntolet thenumberstakeona lifeof theirown.The probabilities—themselves subject to debate—began to be viewed asaccuratepredictions, and theycontributed to theoverconfidence thatwouldbeshatteredinMarch2011.

Japan later added another layer to its earthquake prediction system. In theaftermathof thedeadly1995Kobeearthquake, thegovernmentestablished theHeadquarters for Earthquake Research Promotion. In 2005, the first NationalSeismicHazardMapsofJapanwerepublished.Themapsarebasedonsurveysofactivefaults,long-termestimatesoftheprobabilityofearthquakeoccurrence,and evaluations of strong ground motion. They reflect a belief that“characteristicearthquakes”occuratpredictableintervals.

Theconceptofhazardmappingprovokescontroversyamongseismologistsand emergency planners around the globe. Some geophysicists argue thataccuratehazardmapsareimpossibletoproduce.Ratherthanprovidingreliableinformation,theysay,themapstendtocreateafalsesenseofsecurity.Others,including the U.S. Geological Survey, support hazard mapping, arguing thatalthough the maps are not perfect, they do offer some guidance for purposessuchassettingbuildingcodes.

The maps are based on centuries’ worth of data about earth movements.Evenso,someofthelargestearthquakesinrecentyears,evenbeforeMarch11,2011,occurredinareasorwithadegreeofforcethatsurprisedmanyscientists:theIndianOcean(2004),China(2008),NewZealand(2010and2011).

With expert views ranging from faith that earthquakes could be predictedwithcertaintytodisbeliefthattheycouldbepredictedatall,confusionreignedinthefieldofseismicrisk.Apparentlyevenstate-of-the-artsciencewasunabletoshedmuchlightonthequestionof“howsafeissafeenough”whenitcametobuildingnuclearpowerplantsinJapan.

The nuclear accidents at Three Mile Island in 1979 and Chernobyl in 1986stallednucleardevelopment inmanyplaces. Japanwasn’toneof them.There,constructioncontinuedfullthrottle.DuringthefiveyearsafterChernobyl,Japanaddedfivenewreactors,withseveralmoreunderconstruction.

Amap of Japan showing the location of its nuclear facilities. InternationalNuclear SafetyCenter,U.S.DepartmentofEnergy

TheaccidentatThreeMileIslandUnit2resultedfromaseriesofequipmentmalfunctions,designflaws,andoperatorerrors.Eventuallyabouthalfofthefuelcore melted. Nearly 150,000 people fled their homes. In the end, radiationreleases from the reactorweresmall,but theaccident symbolized to theworld

that nuclear power was not the safe form of energy generation its backersclaimed.

SevenyearsaftertheaccidentatThreeMileIsland,engineersattheSoviet-designed Chernobyl Nuclear Power Plant in the Ukraine were conducting asafety test on the Unit 4 reactor. After a sudden power surge, operatorsattempted an emergency shutdown, but power spiked instead, rupturing thereactorcoreandsettingoffaseriesofexplosions.Thegraphiteusedtomoderatefissioninthecoreignited,sendingamassiveplumeofradiationoverlargeareasof the Soviet Union and Europe. Ultimately, more than 350,000 peopleevacuated and resettled; a large area around the plant has been declareduninhabitable.

The Japanese government and newsmedia portrayedChernobyl as aman-made disaster caused by poorly trained operators and the structural defects ofold,Soviet-built,Soviet-maintainedequipment.Themessagewasclear:suchaneventcouldnothappeninJapan.Butduringthecountry’sownnucleardisasterin 2011, Japan’s Yomiuri Shimbun noted, in understated fashion: “[T]hisassessmentwasoptimistic.”“Wehavetorecognize,”thenewspaperdeclaredinaneditorialinApril,“thatthereisnoperfecttechnology”—adifficultadmissionin a country that prided itself on sophisticated engineering and exactingstandards.

From thebeginningof theeraofnuclearpower, the Japanesepublichadbeenrepeatedlyassuredbygovernmentregulators,plantowners,andthemediathatitwas inherently safe. Eventually, this viewwas generally accepted, despite theperiodic eruption of scandals revealing shortcomings in the competence andintegrityofthoseinchargeofnuclearpowerproduction.

Headlines scattered over the decades built a disturbing picture. Reactorowners falsified reports. Regulators failed to scrutinize safety claims. Nuclearboosters dominated safety panels. Rules were buried for years in endlesscommittee reviews. “Independent” experts were financially beholden to thenuclear industry for jobs or research funding. “Public”meetingswere paddedwithindustryshillsposingasordinarycitizens.Between2005and2009,aslocalofficialssponsoredaseriesofmeetingstogaugeconstituents’viewsonnuclearpowerdevelopmentintheircommunities,NISAencouragedtheoperatorsoffivenuclear plants to send employees to the sessions, posing as members of thepublic,tosingthepraisesofnucleartechnology.

Theutilities and regulators used the same tactic in the summerof 2011 as

local governments debated allowing the restart of reactors shut downafter theFukushima Daiichi accident. Utility employees were encouraged to sendanonymous e-mails supporting a restart or to showup atmeetings anddeliverthemessageinperson.Whenthecollusionwasrevealed,publicopinionturnedhostile.

Throughitall,thenuclearindustryinJapanremainedlargelyunchallenged,insulated by official reassurances that the nation’s elaborate oversight systemwas functioning and the industry’s overall performancewas beyond reproach,despiteafewbadapples.

Challengewasunlikelytocomefromwithinthegovernment.Nuclearenergyin Japan has been described as “national policy run by the private sector.”Regulators and the regulated cohabit peacefully in a “nuclear village” whosemission is topromotenuclearpower.When it comes towho iswatchingoverwhom, the lines often are blurred. A regulator today can become a utilityemployeetomorrowandviceversa.

It’sknownasa“revolvingdoor”intheUnitedStates.InJapan,movingfroma public to a private sector job is called amakudari, “descent from heaven.”1Bureaucrats know that when they are ready to retire, often at an early age, acomfortable job could bewaiting in the industry they once regulated. There’slittleincentivetorocktheboat.

ShortlyaftertheFukushimaaccident,Japan’sYomiuriShimbunreportedthatthirteenformerofficialsofgovernmentagenciesthatregulateenergycompanieswerecurrentlyworkingforTEPCOorotherpowerfirms.

Another practice, known as amaagari, “ascent to heaven,” spins therevolvingdoorintheoppositedirection.Here,thenuclearindustrysendsretirednuclearutilityofficialstogovernmentagenciesoverseeingthenuclearindustry.Again,ferretingoutsafetyproblemsisnotahighpriority.

The ties between government and industry go beyond sharing personnel.Japan’sAsahi Shimbun reported in early 2012 that twenty-two of eighty-fourmembersof theNuclearSafetyCommissionandtwoof itsfivecommissionershadreceivedatotalofabout$1.1millionindonationsfromthenuclearindustryoverafive-yearperiodendinginfiscal2010.One-thirdoftheNSCmembersoncommitteesoverseeingnuclearoperationshadreceivedsuchdonations.PriortobecomingchairmanoftheNSCin2010,HarukiMadarame,thenaprofessorattheUniversityofTokyo,hadreceivedabout$49,000.Criticsofnuclearpowerrarelywereonthereceivingendofsuchlargesse.The“nuclearvillage”looked

afteritsown.

OnDecember26,2004,amagnitude9.2earthquakestruckoffthewesterncoastofSumatra,triggeringadevastatingtsunamiacrosstheIndianOceanthatkilledmore than 286,000 people in fourteen countries. The quake, like the one thatstruckFukushimasevenyearslater,wasasubductionearthquake.And,likethe2011 quake, it caught seismologists by surprise. When the earthquake hit, asubcommitteeoftheNSCwasinthemidstofalongoverduereviewofJapan’sseismic standards fornuclearplants.The review, initiatedafter the1995Kobeearthquake,hadbeeninchingalongforelevenyears.

Amajorissuebeforethesubcommitteewashowtodeterminethemaximumearthquake plants had to be able to withstand. The old standard required thatevery plant be able to survive a nearby magnitude 6.5 earthquake, which inJapanwasfairlycommon.Thenewstandardwouldreplacethatgenericcriterionwith limits tailored to the seismic risks at each plant site. The utilities wereconcerned that the revised standard could effectively increase the earthquakemagnitudetheirplantswouldhavetowithstandandrequirethemtomakecostlyseismicretrofits.

When the new guidelines were ultimately approved in September 2006,criticscalledthemtoovague.AmongtheopponentswasKatsuhikoIshibashi,asubcommitteemember,whosaidtheguidelineswerefullofloopholes.Angryatthe subcommittee’s unwillingness to consider more rigorous standards, heresigned.

As Japan’s largest utility, TEPCO reaped enormous benefits from the blurredlinesbetweengovernmentandindustry.Thecompany’soperatingrecordraisedplentyofwarningsignsaboutthedangersofsuchincestuouspractices,however.AndtheywereapparentwellbeforeMarch2011.

In 2000, Kei Sugaoka, a nuclear inspector working for GE at FukushimaDaiichi, noticed a crack in a reactor’s steam dryer, which extracts excessmoisture topreventharm to the turbine.TEPCOdirectedSugaoka tocoverupthe evidence. Eventually, Sugaoka notified government regulators of theproblem.TheyorderedTEPCO to handle thematter on its own.Sugaokawasfired.

While TEPCOwas ostensibly dealingwith thematter, FukushimaDaiichicontinued tooperate.Then, in latesummer2002, thecompanyadmitted ithad

been falsifying safety records for years, covering up evidence of cracks inthirteenreactorcoreshroudsatall threeof itsplants.Theshroudsarestainlesssteel cylinders that hold fuel assemblies in place and help direct the flow ofcooling water. At a press conference announcing the cover-up, governmentregulatorsdeclaredthatpublicsafetywasnotthreatened.Theyhadreachedthatdeterminationnotfromtheirowninspections,butfromTEPCO’sassurances.

When the cover-up became public, TEPCO’s chairman and presidentresigned. The new chairman declared the falsification of records “the gravestcrisis since the company was established.” Despite the scandal, both formerexecutiveswereretainedasadvisorstoTEPCO.Theirsweren’tthelastheadstorollatthecompany.

•••

InJanuary2007,TEPCOadmittedtomorefalsifiedrecords,involvingatotalofabouttwohundredincidentsdatingbackmanyyears.(Anewspaperheadlinethenext day read: “Not Again!”) It was a year of catharsis for Japan’s nuclearindustry.Sixotherutilitiesrevealedtheirownunreportedsafetyproblems.NISAhaddirectedtheutilitiestoownuptoanysuchissues,hopingtoheadoffpublicopposition to new reactor construction. Whether the outpouring of misdeedshelpedorhurtNISA’scauseisnotclear.

Among the incidents TEPCO divulgedwere problems at its Kashiwazaki-Kariwa reactors on Japan’s west coast. Kashiwazaki-Kariwa is the world’slargest nuclear generating station, capable of producing 8,212 megawatts ofelectricity, nearly double Fukushima Daiichi’s output of 4,696 megawatts. Inone instance, during a routine government inspection at Kashiwazaki-Kariwa,operators discovered that a component of the emergency core cooling systemwasn’t working. Workers made adjustments in the control room to make itappearthepumpwasfunctioning.

AccordingtoTEPCO’sexplanation,theutilitywasn’ttheproblem;theruleswere. “[F]alsification occurred because passing the inspections became theobjective,”thecompanytoldthegovernment.TEPCOadmittedonlytohandlingdata“inappropriately,”nottolyingtoinspectors.Forexample,theutilityfailedto report that control rods came loosemore than once in the reactor cores atFukushimaDaiichi, in one instance triggering a criticality accident that lastedseven and a half hours.Technically,TEPCOacted legitimately.Reporting thecriticalitymishap,forinstance,wasnotrequiredunderJapan’ssafetyrulesatthe

time.

YES,THEPAPERWORKMATTERS—ALOT

Fudging figures, doctoring reports, and creative accounting may seemminor,thoughdeplorable,offenses.Buttheyarenotminor.Whenitcomesto nuclear plant safety, the value of accurate, complete, and reliablepaperworkcannotbeunderestimated.

IntheUnitedStates,NRCinspectorsauditonlyabout5percentoftheactivities at nuclear plants, according to senior managers at thecommission.Most of these audits involve reviewing the records of testsand inspections performed by plant workers. The NRC inspectorsthemselves witness only a very small fraction of actual tests andinspections. If safety inspectors couldnot trust aplant’spaperwork, theywouldhavetopersonallyobservemanymoreactivities thantheydonowto gain confidence that their assessment of the plant’s safety was areflection of reality. To put this anotherway:whenworkers feel free toprepare fictional accounts of tests and inspections, nuclear safetyassurancesbeginmorphingfromnonfictiontofictionaswell.

ThencametheearthquakethatdamagedKashiwazaki-Kariwa.ItoccurredonthemorningofJuly16,2007,witharupturealongthefaultthatacourthadruledin2005didn’texist.Theplanthadbeenbuilttowithstandasmallerquake;thisone,withamagnitudeof6.8,createdgroundmotiontwoandahalftimesgreaterthan that plant had been designed for. The episode raised questions aboutTEPCO’sresponsetosuchcrisesthatwouldprovealltoorelevantin2011.

When the quake struck, three of the seven reactors were at full power; afourthwasintheprocessofstartingup.Therestwereoutofserviceforrefuelingandmaintenance. All four operating reactors automatically shut down. A firebroke out in an electrical transformer. Because it was a national holiday, theplantwas shorthanded. Emergency response crewswere difficult to assemble.The quake had damaged the plant’s own fire extinguishing system. Cityfirefighterswerepulledawayfromlocalemergenciesandsenttotheplant;theirarrivalwasdelayedbyanhourbecauseofquakedamage.

Atthetime,PrimeMinisterShinzoAbecriticizedTEPCOforbeingtooslow

inreportingproblemsatKashiwazaki-Kariwa.“Nuclearpowercanonlyoperatewith the public’s trust,” he told reporters. The International Atomic EnergyAgencysentinspectorstotheshakenplantandconcludedthatthedamagewas“lessthanexpected.”Theagencydid,however,recommendareevaluationoftheseismicsituationatKashiwazaki-Kariwa,especiallytheexistenceofactivefaultsbeneath thesite.Later in2007,TEPCOreporteda fourteen-mile-long(twenty-three kilometers) active fault in the seabed eleven miles from Kashiwazaki-Kariwa.Thecompanysaidithadknownaboutthefaultsince2003,butdidnotreport its findings then because TEPCO staff didn’t believe the fault wouldproduceanearthquakelargeenoughtothreatenthereactors.

Immediately after the 2007 earthquake, the utility took all seven of theKashiwazaki-Kariwa reactors out of service to check for damage and upgradetheirseismicresistance.2Without20percentofitsgeneratingcapacity,TEPCOposted its first loss in twenty-eightyears, totaling$1.44billion. Itsstockvaluedropped30percent.

TobolsterconfidenceinthewakeoftheKashiwazaki-Kariwadebacle,anewTEPCOpresidentwasnamed in2008.MasatakaShimizu tookover, replacingTsunehisa Katsumata, who became chairman. The front office shuffle wasgettingalmostroutine:Katsumatahadtakenthetopjobinthewakeofthe2002falsificationscandal;nowShimizu,aforty-yearveteranofthecompany,steppedin.BothmenhadspenttheirentirecareersatTEPCO.Shimizumadecostcuttinga high priority, and within two years had returned TEPCO to the black,exceedinghistargetof$615millionincuts.Hissecret?Reducingthefrequencyofinspections.

Direct structural damage is not the only danger that earthquakes can pose toJapan’s coastal nuclear plants. They can also cause devastating tsunamis, asbecameobvious inMarch2011.Yetpredicting tsunamis is a similarly inexactscience. Given the uncertainties, developing standards for tsunami protectionposedanotherconundrumforregulatorsandplantowners.

On tsunami protection, TEPCO took its cue from government, and Tokyoseemed innohurry.The lengthysafetyreviewthat led to the2006earthquakeguidelinesdidnotaddresstsunamis.Proposedtsunamiguidelinesweremovingthroughtheirownseparatereviewprocessatapacealmostasslowasthetempoatwhich the quake standards had progressed. The nuclear industry also had astrongpresenceinthesedeliberations.

JustasthescienceofseismologyhadevolvedintheyearssinceJapan’sfirstnuclearplantswerebuilt, tsunami research, anewer field,wasgaininggroundrapidly.And Japan also provided an ideal laboratory: theSanrikuCoast alonehad experienced four destructive tsunamis in a little more than a century,includingthe1896quakeandwavethathadarun-upheightofnearly125feet.

Those tsunamis had struck to the north of Fukushima Daiichi. Whenconstruction began on the reactors in the late 1960s, engineers dismissed thelikelihood that the plant location might be vulnerable. Based on the worsthistorical tsunami on record at the Fukushima site—resulting from a 1960earthquake inChile—thereactorsweredesignedtowithstanda tsunamiwithamaximumheightofabouttenfeet(3.1meters).TEPCOwassoconfidentofthisdatapoint that thecompanyactually lowered theheightof thebluffwhere theplantwastobebuiltbymorethaneightyfeet(twenty-fivemeters).Thatmadeiteasiertodeliverheavyequipmenttothesiteandtopumpcoolingwaterintothereactors. The company also said the excavation would enhance earthquakeprotection by placing the reactors on bedrock—albeit bedrock far below thenaturalelevation.

So confidentwasTEPCO that in 2001 it submitted toNISAa single-pagetsunamiplanthatruledoutthepossibilityofalargetsunamihittingtheplantandcausingdamage.Thecompanyprovidednodatatosupportitsconclusions,andNISAapparentlyaskedfornone.“Thisisallwesaw,”aNISAofficialtoldtheAssociated Press, which located the TEPCO document a decade after it wassubmitted.“Wedidnotlookintothevalidityofthecontent.”

NISAlackedauthoritytoquestiontheaccuracyofTEPCO’spresenteddatainanyevent,because tsunamiplans fromutilitieswerevoluntaryat thisstage.TEPCO provided its information in advance of new tsunami guidelines beingdeveloped by the Japan Society of Civil Engineers. That group called forprotectivemeasurestobebasednotonlyonhistoricaltsunamidata,butalsoonwaveheightscalculatedbynumericalmodels,takinguncertaintiesintoaccount.In the one-page plan for Fukushima Daiichi, TEPCO provided its projectionusing thismethod:awavenohigher thannineteenfeet (5.8meters),generatedby a magnitude 8.0 quake modeled after one that had occurred in 1938.Accordingly, theutilitymadesomemodifications, includingraising themotorsoftheseawaterintakepumps.(In2009,TEPCOfurtherrefinedthecalculationsandraiseditsestimateofthemaximumtsunamiheighttoabouttwentyfeet.)

Theprevailingwisdom,basedonthehistoricalrecord,wasthatearthquakeslarger than magnitude 8.0 would not occur in the offshore trench near

Fukushima, although they had occurred further north off the Sanriku Coast.However,in2002,theHeadquartersforEarthquakeResearchPromotionsaiditwas possible that earthquakes similar to the 1896 Meiji Sanriku earthquake,whichhadanestimatedmagnitudeof8.3,couldoccuranywherealongthetrenchasfarsouthastheBousoupeninsula,wellbelowFukushimaPrefecture.

TEPCOpaidnoattentiontothatpredictionuntil2008,whenexpertswarnedthat the utility’s tsunami assessments could have underestimated the potentialsizeof earthquakesoff theFukushimacoast.As a result,TEPCOconducted acalculationassumingthatanearthquakecomparabletoMeijiSanrikuoccurredinthatarea.Basedonthismodel,theutilitynowpredictedatsunamiuptothirty-fourfeet(10.2meters)highneartheplant’sseawaterintakepumps.Awavethatlargecouldsweepinlandandreacharun-upheightofmore thanfifty-onefeet(15.7meters)aroundUnits1 through4atFukushimaDaiichi.ButTEPCOdidnot consider these results realistic,maintaining that the undersea faults in theareawerenotthetypecapableofcausinglargetsunami-generatingearthquakes.

Reaching even further back in seismic time, however, one potentialcounterexample stood out: the 869 A.D. Jogan earthquake and tsunami. Theexact origin of the earthquake, believed to have been a magnitude 8.6, wasunknown, but scientists had found evidence of geologic deposits from thetsunamiwellinlandinareasnotthatfarnorthofFukushimaDaiichi.CouldsuchadevastatingearthquakeoccurclosetoFukushimaafterall?Concerned,TEPCOrananother calculationassuminganearthquakeas largeas Joganand found itmightproduceatsunamiashighasthirtyfeet.TheutilitythensurveyedtsunamidepositsaroundFukushimaPrefectureandlocatedsomejustnorthoftheDaiichisite, but it found their patterns to be inconsistent with its model. TEPCO’sconclusion:furtherresearchwasneeded.

AtugboatthatwassweptinlandbytheMarch11tsunamiandlefttorestinthedevastatedtownofOfunato,northofSendai.SimilarscenesofdestructioncouldbefoundalongthebatteredcoastlineofnortheasternJapan.U.S.Navy

TEPCO managers discussed the new wave projections internally andconsideredcountermeasures.Butultimately thecompanydidnotseeaneed toprepareforwhatitstillregardedasahighlyimprobableevent.Itdidn’tmoveitsbackup diesel generators out of the turbine building basements. Nor did itenhanceprotectionbyconstructingalargeseawall.AlthoughtheSanrikuCoastranks as one of the most “engineered” in the world—with tsunami barriersstretchingformiles—TEPCOmanagementfearedthatatallbarricadeinfrontofa nuclear plant would send the wrong message to the public. “Buildingembankments as tsunami countermeasures may end up sacrificing nearbyvillages for the sake of protecting nuclear power stations,” according to aTEPCOdocument.“Itmaynotbesociallyacceptable.”

NISA conducted hearings on earthquake and tsunami hazards at nuclearplants in June2009.Thepanel examiningFukushimaDaiichi didn’t include atsunamiexpert.Earthquakeswereregardedasamoreprobablethreat,andthat’swhatthecommitteefocusedon.Butwhenthepanel’sfindingswerepresented,arespected seismologist warned NISA that a tsunami at the plant could be asdevastating as an earthquake. When he asked why the 869 A.D. Joganearthquake,whichsentwatermorethantwomilesinland,wasnotincorporatedintothepanel’sassessment,aTEPCOofficialdismisseditasa“historic”eventnotrelevant to thedeliberations.AlthoughNISApromised tofollowupon theissue, at the next meeting Fukushima Daiichi’s existing preparations weredeemed sufficient. Without pressure from regulators, TEPCO continued to

investigatetheJoganissueonaslowtrack.TEPCOdideventuallygetaroundtoreportingnewtsunamidamageassessmentstoNISA—onMarch7,2011.

Four days later, at the U.S. NRC, the prediction that things could get “reallyugly” at FukushimaDaiichiwas coming true. Inside theOperationsCenter atWhite Flint, experts watched the crisis develop with growing alarm—andfrustrationatthelackofinformationortheabilitytorespond.TheNRC’searlyofferofengineeringassistancetoJapanhadbeenmetwithsilence,andtheNRCstaff,likeordinarymembersofthepublic,hadaccesstonothingbutspottyandconfusingmediareports.“Thisisnotourevent,”NRCchairmanGregoryJaczkowarnedhisimpatientteam.

But that didn’t preclude the agency’s experts from parsing every detailtricklingoutofJapan.IntheearlyhoursofMarch12,DanielDorman,adeputydirectorworkingintheOperationsCenter,calledJaczkoathometoalerthimtotheexplosionatUnit1.Dormanandhiscolleagueswerewatchingitreplayedonatelevisionscreen.

“It’s an initial short duration pulse,” Dorman told his boss, “like anexplosion,followedbyalargecloud,andthenthereissomesubsequentfootageshowingwhat appears to be the frames of the building that—the upper wallsaroundthe—whatwouldbethemetalframeworkabovetherefuelinglevel,it’sbeenopeneduptotheIbeams.”Hecontinued,“We’restillworkingoffofwhatwegotonthemedia.Butitisaverydisturbingimage.”

Dormanwasn’taloneinhisconcern.At 5:12 a.m. Washington time, the NRC’s Robert Hardies e-mailed his

colleagueMatthewMitchell:“Mydogwokemeuptogoout.IturnedonCNN.They had breaking video they could not explain. To me it looked like acontainmentbuildingdisappearinginanexplosivecloud.WTF.”

3

MARCH12THROUGH14,2011:“WHATTHEHELLISGOINGON?”

Atfirst,plantbossMasaoYoshidathoughttheviolentmotionbeneathhisfeetat3:36p.m.March12wasanotherearthquake.Thencamepotentiallyworsenews:the topof theUnit1 reactorbuildinghadblownoff;only thesteel frameworkremained.

Fourminuteslater,theharriedteamintheplant’semergencyresponsecenterjoinedtherestof theworldwatchingtheexplosionreplayedonTVscreens.Ahugebillowofwhitesmokeanddebrisexpandedskyward,driftingawayontheprevailingwinds.

Acheckofthejury-riggedgaugeshowedthatthewaterlevelinsidetheUnit1reactorhadnotchanged:5.5feetbelowthetopofthefuel,orabout21.5feetbelownormal.Thefuelhadstartedmeltingabouttwenty-onehoursearlier.Also,thepressurewithinthereactorvesselhadnotdropped,suggestingthattheworst-casescenario—thattheexplosionhaddamagedthereactorvesselitself—hadnotoccurred.

ThislookedtopersonnelattheplantandatTEPCO’semergencyoperationscenter like a hydrogen explosion. But fromwhat source? PrimeMinisterKanhad asked the Nuclear Safety Commission chief, Haruki Madarame, thatmorning about the likelihood of hydrogen igniting, and had been assured thatthiswasunlikely.

Duringnormalreactoroperations,nitrogengasisaddedtothedrywell—partof the primary containment structure—to preclude an explosion of hydrogenshouldanyaccidentoccur.Hydrogencannotigniteunlessoxygenispresent,sosubstituting nitrogen for oxygen—a process called “inerting”—eliminates thepossibilityofavolatilemixforming inside thedrywell.Theatmosphere in the

reactorbuildingitselfwasnotinertedbecauseregulatorsneverthoughtitwouldbe necessary; protecting the containment from rupture would be sufficient topreventradiationleaks.Now,somehow,hydrogengashadapparentlymigratedtoanareawherenoonehadexpectedittobe.

Theinitialreactionamongthestartledworkerswasdenialthatthehydrogenwasgenerated fromdamagednuclear fuel.Yoshida first thought theexplosionmight involve the turbine generators, which use hydrogen gas as a coolingmediumintheiroperation.However, thiswasruledoutwhenreports indicatedthattheUnit1turbinebuildinghadnotbeendamagedintheblast.

Unit1afterahydrogenexplosionblewoffthetopofthereactorbuilding.TokyoElectricPowerCompany

Anothertheorysuggestedthatthespentfuelpoolinthe“attic”ofthereactorbuildingwasboilingand thefuel therewasno longercompletely immersed. Ifso, the overheated cladding of the fuel rods could have reactedwith steam to

generatethehydrogengasthatignited.Withoutworkinginstruments,therewasnowaytocheckthewaterlevelortemperatureofthepool.Butitwasnotclearhowsomuchofitcouldhaveboiledawayinsuchashorttime,givenwhattheoperators knew about the amount of heat generated by the relatively smallquantity of fuel in the pool: only 292 spent fuel assemblies and 100 newassemblies.(Thenewassembliesweretheretoawaitthenextrefueling.)

Thenanotherhypothesiswasputforward:theextremepressureandheatthathadbuiltupbeforeventinghadloosenedboltsandsealsinthereactor’sdrywell,allowingradioactivesteamandhydrogentoleakintothereactorbuilding,whereasparkorstaticelectricitytriggeredtheblast.Orperhapswhenthecontainmentwasvented,hydrogenunderenormouspressurehadleakedoutoftheventpipeinto the reactor building before it could be expelled through the tall exhauststacksharedwithUnit2.Normally,ventilationfanswithinthereactorbuildingmighthavehelpedtodrawanyhydrogenupandoutofthebuilding,butthefanscouldn’tworkwithoutelectricity.Instead,thegaswouldhaveaccumulateduntilit became concentrated enough to explode. No matter what the hypothesis,though,onethingwasclear:ifthecontainmenthadbeenventedsoonertoreduceits pressure, thismight have prevented hydrogen—and fission products—fromleakingintothereactorbuilding.

For the hapless crew in the plant’s emergency response center, there wasmorebadnews:fallingdebrishaddamagedtheelectriccable thatworkershadspent hours laying andwerewithinminutes of energizing to restore power toUnits1and2.TheexplosionhadalsodamagedthefirehosesthatworkershadcarefullyarrangedtoinjectseawaterintoUnit1.AlthoughradioactivelitterwasnowscatteredaroundtheUnit1reactorbuilding,Yoshidaorderedhisemployeestoget thehosesworking.Thefireengines injectingfreshwater intoUnit1haduseduptheirsupplynearlyanhourearlier.Theneedtogetwaterintothecorewasstillimperative,andtheworkershadbeenveryclosetobeingabletosupplyit. The explosion set them back by several hours, but despite the hazardousconditionstheyrepairedthedamageby7:00p.m.

Meanwhile, justbeyond thesix-mile (ten-kilometer)evacuationzone, residentsofthecoastaltownofNamiethoughttheyhadfinallyreachedsafety.Earlierthatmorning theyhadbeen rousted from theevacuationcenters towhich theyhadfled toescape the tsunami;now thosecenterswere tooclose toanewdanger:Fukushima Daiichi. Their next haven was a school. Children played in theschoolyard. Adults, dressed in heavy winter coats, sat together on the

gymnasiumfloororcookedamealoutside.WhiletheworldwatchedimagesofthegiantcloudbillowingfromUnit1,thoseclosesttoitwereunawarebecauseofthelossofcellphoneandtelevisionservice.

As the Namie evacuees would later learn, merely being farther from thedamaged reactorswould not necessarily protect them. Luckwas on their sidethat night, however, because the emissions fromUnit 1were relatively small,and the prevailing winds blew them primarily northward along the coast andthenouttosea.

Almost from the beginning of the accident, an early-warning system hadbeenmakingominouspredictionsaboutthedangerthattheNamieevacueesandotherpeoplenearFukushimaDaiichicouldfaceshouldconditionsworsenattheplant. The System for Prediction of Environmental Emergency DoseInformation, or SPEEDI,was developed by the Japanese after theThreeMileIsland accident. It went into operation in 1986. If radiation is released in anaccident,SPEEDIusesreal-timemeasurementsfromthenuclearplant togetherwithmeteorologicaldatatopredictwheretheradioactivitywillspreadandhowintenseitwillbe.Whenactualradiationreleasedataareavailable,thesystemisfar more useful in assessing risks and defining evacuation areas than theconcentric zones arbitrarily drawn around a plant. The system is continuallyupdatedandmonitoredfromanofficeinthecapital.

Thedaybefore,whenTEPCOdeclaredanuclearemergency,SPEEDIhadswitched to emergency mode, ready to track any releases from FukushimaDaiichiandguidedecisionsaboutevacuationsbasedonthelocationofradiationplumes.Therewasoneproblem:FukushimaDaiichihadnopower.Asaresult,whenradiationwasreleased,theplant’son-sitemeasuringdeviceswereunabletogatherandtransmitdataaboutittoSPEEDI.Withoutsuchdata,allSPEEDIcoulddowasindicatethedirectioninwhichtheradiationwouldtravel.1

Those projections were duly passed from the Education Ministry, whereSPEEDI is housed, to NISA, which forwarded them to the prime minister’soffice. But they came with a caveat: their reliability could not be guaranteedbecause no one knew how much radiation was actually being released. As aresult,thereadoutswerenevershowntotheprimeminister.

Fourdays into the accident, thenewsmediabeganasking for theSPEEDIdata.ThatpromptedameetingoftopEducationMinistryofficialswhoworriedthat “a release of the predictions could cause people unnecessary confusion.”With that, responsibility for SPEEDI datawas handed off to theNSC,whose

chief,Madarame,dismissed thecalculationsasnobetter than“amereweatherreport.”

TheNamie evacuees at the schoolhadno inkling theywere at riskuntil aTEPCO employee showed up late on the afternoon ofMarch 12 in protectiveclothing, carrying a dosimeter. Less than an hour after the Unit 1 explosion,radiationreadingsattheplantboundaryhadsoared.Buttheemployeereassuredtheworried families that theywere safebecause theywereoutside theofficialevacuation zone—and then he jumped in his car and left. About 6:30 p.m.,military trucks arrived at the school. With little official explanation, theoccupants were made to pack up their few belongings and head out into thenight, once again in search of safety. Other evacuees weren’t as lucky; someremainedinareasthatwereinthepathofradiationplumesuntilMarch16beforebeingtoldtoleave.

In Tokyo the evening ofMarch 12, officials gathered in the primeminister’soffice,struggling to figureoutwhatwashappeningatFukushimaDaiichi. Justbefore6:30p.m.,adecisionwasmadetodoubletheevacuationzonetoa12.4-mile(twenty-kilometer)radiusaroundtheplant.Kanannouncedthedecisiononnationaltelevision,tellinghisaudiencethatJapanwasfacingan“unprecedentedcrisis.”JoininghimwasCabinetSecretaryEdano,whoreassuredthepublicthatalthoughanexplosionhadoccurred in theUnit1 reactorbuilding, theprimarycontainmentremainedintactandtherewouldbenomajorescapeofradioactivematerial. “Please remain calm,” Edano told viewers. It was advice thegovernmentrepeatedoften.

AbsentfromthisbriefingwasKoichiroNakamura,deputydirectorgeneralatNISA,whohadbeenhandlingregularupdatesforthemedia.Nakamura’scandoratpressconferencesearlierthatdayapparentlyhadgottenhiminhotwaterwithKan’soffice.Inamorningsessionwithreporters,Nakamura,whohadadegreeinnuclearengineering,wasaskedifthefuelhadstartedtomelt.Hereplied:“Wecannot deny the possibility.” Four hours later, at another briefing, Nakamurasaid:“Itlookslikeacoremeltdownisoccurring.”Ashorttimelater,NISAwasnotified that the prime minister’s office had to clear all statements about thesituation, and that NISA also needed to obtain permission from Kan’s officebeforeholdingfurtherbriefings.Nakamuraaskedtobereplaced.

Whenreportersgatheredforanotherbriefingshortlyafter9:00p.m.,anewNISAspokesmanwasincharge.Askedaboutmediaaccountsofameltdown,thespokesmanbackpedaled,saying:“Theconditionofthecorehasnotbeenclearly

identified yet.” The word meltdown was not mentioned. The next morning,another NISA briefer was asked about the likelihood of a meltdown. Theanswer:“Thelikelihoodcannotbedeniedbecausesuchamaterial[cesium]hasalreadybeendetectedandwemustkeepthatinmind.”

In short, if reporters were looking for definitive answers from thegovernment’s nuclear safety officials, NISA wasn’t providing them. In itssteadfasteffort toavoid thewordmeltdown,NISAultimatelycameupwith itsownterminology:fuelpelletmelt.(TEPCOalsoeschewedmeltdown,preferringcoredamage.)AlthoughNISA’sclassificationmadetechnicalsense,theagencyhadlittlebasis toavoidconcludingthatafull-scalemeltdownhadoccurred.Inthe minds of many listeners, its careful parsing of words was a distinctionwithoutadifference.

During the afternoon of March 12, after the explosion in Unit 1, Kan wasmeeting in his office withMadarame and several others when the discussionturnedtothequestionofinjectingseawaterintotheUnit1reactorasalast-ditchattempttocoolthedamagedcore.

TEPCOofficials,realizingthattheinjectionofseawaterofferedperhapsthelast hope of cooling the reactor, had already given the go-ahead. Thatinformationwaspassedalong tomembersof theEmergencyOperationsTeamworking in thebasementof theprimeminister’sofficebuilding.But thenewsnevermadeitupstairstoKan’soffice.

Thedecisiontouseseawateristhedeathknellforareactor,andinthiscaseitwouldsendanunequivocalsignalthatUnit1hadnowbeenwrittenoffbyitsowners as a piece of radioactive scrap. Seawater is highly corrosive to theinternalpartsofanuclearreactor;eventhefreshwaterusedinareactorisfilteredtoprotect components from impurities.ThePacificmight cool the core, but itwouldfinishthejobofdestroyingthereactor.

Kan askedMadarame about the possibility that the seawater could triggerrecriticality—anuncontrolledchainreaction—inthedamagedfuel.2Madaramereassured the prime minister that this was unlikely. Participating in theconversation was TEPCO’s liaison, Ichiro Takekuro, who interpreted thediscussiontomeanthatthegovernmentmightnotapproveofinjectingseawater.

Shortlyafter7:00p.m.,TakekurocalledplantsuperintendentYoshidatotellhimabouttheconversation.Yoshidasaidthattheseawaterinjectionhadalreadybegun.Takekurotoldhimtostopitbecausetheprimeminister’sofficewasstill

weighing that option.An angryYoshida called TEPCO headquarters andwastoldhehadnochoicebuttosuspendtheinjectionpendingadecisionbyKan.

Yoshida knew that if he stopped the injection, he might not get the jury-riggedpumpingsystemtoworkagain.Andheknewthatcontinuingtogetwaterinto the corewas thehighestpriority, regardlessof thegovernment’s apparentdithering. In a moment of bare-knuckled defiance, Yoshida summoned thepersoninchargeoftheinjectionworkandwhisperedinstructions:“I’mgoingtodirect you to stop the seawater injection, but do not stop it.” Then, in a loudvoice,heard in theplant’semergency responsecenter—and,viavideo feed, inTokyo—Yoshida ordered that the pumping be halted. Finally, at 8:20 p.m.,Takekuro delivered word that the primeminister had given the okay and theinjection could resume. By then, however, Yoshida had a new spate ofemergencies.

OnSaturdaymorning,March12,NRCchairmanGregoryJaczkowasenroutetoan11:00a.m.meetingattheWhiteHousetodiscussthesituationinJapanwhenhe received an update. Informationwas still in short supply at theNRC,withmost coming via media outlets. The NRC wasn’t alone; the Departments ofState,Defense,andEnergy,theU.S.AgencyforInternationalDevelopment,andespeciallytheU.S.EmbassyinTokyowerealsolaboringtolearnmore.

Martin Virgilio, the NRC’s deputy executive director for reactor andpreparednessprograms,wasmanningtheOperationsCenteratWhiteFlintandhadjustgottenoffthephonewithnuclearindustryofficials.Theyhadprovidednew information that Virgilio, a level-headed thirty-four-year veteran of theNRC,wantedtopassalongtoJaczkobyphone.

Virgilio’s information had come from the Institute of Nuclear PowerOperations (INPO), an industry group created after the Three Mile Islandaccident tobolsternuclearsafety initiativesandenhance the industry’s tatteredpublicimage.INPO,anditsinternationalcounterpart,theWorldAssociationofNuclear Operators (WANO), had been working sources to learn as much aspossible.(OnevaluablesourcefortheindustryandtheNRCwasChicago-basedExelonCorporation,whichoperatesmoreboilingwaterreactorsthananyotherU.S. utility.) The call provided the NRC with important details, includinginformationgleanedby industrypeopledirectly fromtheircontactsatTEPCO.Notalloftheinformation,however,wasaccurate.

INPO andWANO representatives told Virgilio that a hydrogen explosionhadoccurredintheUnit1reactorbuilding,confirmingtheassessmentofNRC

staffmemberswhohadwatchedtheexplosionontelevision.Itwasasignificantdetail. If the explosionwas in the turbine building, the hydrogen could easilyhavecomefromsourcesotherthandamagedfuelinthereactorcoreand/orspentfuelpool.Butifthereactorbuildingexploded,itwasafarmorelikelyindicatorofextensivefueldamagesomewhere.

As the industry representatives and theNRC sharedwhat they knew, theypieced together this picture of the situation at Fukushima Daiichi: after theexplosion, radiation levels at the plant boundary had jumped to one hundredmillirem(onemillisievert)perhour—abouttenthousandtimesbackground—butthendroppedtofiftymilliremperhour.TheprimarycontainmentatUnit1wasbelieved to be still intact. Iodine and cesium isotopes had been detected,indicatingsomemeltingoffuel.Abouteightinches(twentycentimeters)ofthefuel inUnit1hadbeenpartiallyexposed,andmaintainingwater levels in thatreactorvesselwasproblematic.TherewasanunconfirmedreportthattheUnit1containment was being filled with borated seawater using fire trucks. Unit 3appeared tobe incold shutdown.Unit2’sRCICcooling systemseemed tobedoing its job of transferring heat from the core to the torus, but therewas noelectricalpowertorunthepumpsthatcooledthetoruswaterandtransferredheatto thesea. Ifheatcouldnotbe removedfromthe toruswater, thecontainmenttemperatureandpressurewouldcontinuetorise.

AlthoughtroubleseemedtobebrewingatUnit2,theUnit1situationtoppedeveryone’s list of concerns.And in hindsight, theywere notwrong—Unit 1’sdamage was actually far more extensive at that point than the briefing hadindicated.However, theworseningconditionsat theothertwounits,aswellasUnit4,wouldsoonviefortheNRC’sattention.

For the NRC, the fragmentary information spilling out of Japan posed acombination of challenges the staff had never encountered during emergencydrills; nobodyhad trained for an event this severe.The experts atWhiteFlintand elsewhere within the agency were largely forced to rely on secondhandinformationandcomputeranalysesthatmightnothaveaccuratelyreflectedwhatwas actually happening. At the same time, the NRC, as home to the U.S.government’s resident experts in nuclear power, was being counted on toprovide guidance to ensure the safety of Americans scattered all over Japan,including 38,000 U.S. troops, 43,000 dependents, and 5,000 civilian defenseemployees,plusembassypersonnel,businesspeople,students,andtourists.

One of Jaczko’smain concerns, even at that early stage,was the potentialradiological impact of the accident andhow far away from the site significant

radiation exposure could occur. The NRC’s Protective Measures Team hadalreadybegun to runcomputer simulations,usingacodecalledRASCAL(theRadiological Assessment System for Consequence Analysis) to address thisquestion. However, as was the case with SPEEDI, the RASCAL simulationswere of limited valuewithout data on howmuch radiationwas actually beingreleased.VirgiliotoldJaczkothat,basedoncrudeassumptions,includingatotalfailureoftheUnit1reactorcontainmentandseverecoredamage,theexposurelevelsthatwouldtriggerevacuationbyU.S.standardswouldbeexceededatfiftymilesfromFukushima.3JaczkoaskediftherecouldbedangerevenfartherawayandVirgiliosaidtheNRChadn’tmodeledpastthatpoint.Hedidn’tmentiontoJaczkothattheRASCALcodewasonlygoodouttofiftymiles.

In addition to monitoring what was happening in Japan, the staff at theOperations Center was beginning to focus on a different kind of crisis: apotential public relations nightmare at home. The NRC oversees twenty-threereactors of the same design as the units in trouble at FukushimaDaiichi. Theagency had been dragging its feet for years on addressing a host of difficultissues, including revising seismic safety rules. And now the NRC faced theunpleasanttaskofhavingtodefenditsoversightbeforeanewlyskepticalpublic.

AlthoughearlynewsreleasesofferedgeneralassurancesaboutU.S. reactorsafety—“Nuclear power plants are built to withstand environmental hazards,includingearthquakesand tsunamis”—theNRCdidn’tknowenoughabout theJapaneseplants tosaywithcertainty that thesafetysituationwasanybetter intheUnitedStates.Forinstance,theNRCdidnotknowatthetimewhetherJapanhadinstalledhardenedventsatitsMarkIboilingwaterreactorsbackwhenmostU.S. plants did so, at the urging of the NRC, in 1989.4 And even if NRCofficials could legitimately claim U.S. plants were safer, they had to treadcarefullyorriskembarrassingamajorU.S.ally.OneNRCstaffercalledthisa“slipperyslope.”

WhiletheNRCwastryingtoprymoreinformationfromJapan,italsofacedpressure tobemore forthcoming.Someof thepushwas coming from its ownstaff. As Jaczko was heading home after the White House meeting, Virgilioasked his boss if the NRC might step ahead of the other federal agencies,“sanitize our Qs and As [about the accident] and post them on the website.”Jaczko said no. “At this point, all of the public communication needs to becoordinated,”hesaid.“[L]et’scontinuetokeepitwithinthefederalfamily.”

At thatmoment, the federal familywas engaging in a little sibling rivalry,

withtheNRCbuttingheadswiththeDepartmentofEnergy(DOE),whichfieldsitsownteamofnuclearexperts,manyofwhomworkinthenationallaboratoriesaround thecountry.Thoseexpertswere“chompingat thebit” toget involved,whichdidn’tsitwellattheNRC.“[S]omebodymightwanttocallDOEandtellthem to tell their labs to cool it,” said theNRC’sBrianSheron onMarch 12,“becausethelastthingwewantisthelabsgoingoff,talkingtothepress,talkingaboutconsequencesandallsortsofotherstuff.”

State officialswere beginning to pressNRCofficials for an assessment ofradiationriskstotheirresidents.5“Ithinkweneedtodomorewiththestates,”Virgilio told Jaczko.That’swheremost requests for informationwere comingfrom,hesaid.Sofar,anyway.TheU.S.newsmedia,alreadyplyingtheNRCforinformationabouteventsinJapan,werealsolookingforalocalangle.

Eventually, Jaczkoandhis teamknew, theNRCwouldhave toanswer thequestion: could Fukushima Daiichi happen here? For the NRC, that was theultimate“slipperyslope.”

“Ithink. . . it’sinevitablethatwe’regoingtogetthosequestionsandcallsfor comparisons of U.S. facilities to [those in] Japan,” the NRC’s BrianMcDermott,joiningVirgilioonthecall,toldJaczko.Jaczkoagreedandtoldhiscrewtostartworkingonsometalkingpoints.

Later that day, the conversation in theNRC’sOperationsCenter turned tocrafting acceptable answers, first for the states and then, ultimately, for themediaandthepublic.Stayingontopofthemessagecouldbedifficult,theNRCteamagreed.

“[I]f we’re trying to restrict the information, or at least control theinformation, that we’re getting outside, anything that you give a state or agovernor,you’renotgoingtobeabletocontrolwhattheydowithit,evenifyouask them to keep it close,” said Dr. Charles L.Miller, an NRC veteran whooversaw state programs. Officials in western states, in particular, wanted toknowwhattheNRCknew,especiallythelikelihoodofameltdowninUnit1andthe possibility of radiation reaching the United States. So far the NRC hadrefused to make any public statements about exactly what was happening atFukushima.

Together,ahandfulofstaffmembersdraftedthetalkingpoints.Thegistofthemessage, they agreed, should be this: The NRCwill not speculate. Don’tbelieveeverythingreportedinthemedia“bytheso-calledexperts.”Becautious.“And avoid answering questions on whether it could happen here,” Miller

warned.“Imean,Idon’tthinkwe’rereadytodothatyet.”Asthecrisiscontinued,theNRCexertedconsiderablediscipline,refraining

from appearing to second-guess the plant operators or to make pessimisticassessmentsaheadoftheJapanese.Thepressreleasesitissued,whileseekingtoreassureAmericans, flatly stated that “theNRCwill not comment on hour-to-hourdevelopmentsattheJapanesereactors.”Asforspeculating,BillBorchardt,the NRC’s director of operations, had his own advice for his impatientcolleagues:“Don’t...scratchtheitch.”

Within minutes of getting the official go-ahead from Tokyo to “resume”injecting seawater intoUnit 1,Yoshida found the next problem landing in hislap.At8:36p.m.onMarch12,thegaugemonitoringwaterlevelsinUnit3ranoutofbatterypower. Infact,problemsinUnit3hadbeenquietlymultiplying.They,too,involvedcoolingthecore.

Awareearlyonthatbatterylifewasanissue, theUnit3shift teamhadcutoff all nonessential power loads, fearful that if the RCIC stopped for somereasontheremightnotbeadequatepowertorestartit.Withbatterypoweralone,operators were able to keep the cooling system running by continuouslymonitoringthewaterlevelandcontrollingtheflowrate.

BecauseUnit3appearedtobestablewiththeRCIClimpingalong,YoshidaandhisworkershadfocusedonrestoringpowertoUnits1and2.Butat11:36a.m.onMarch12,theRCICinUnit3stoppedandcouldnotberestarted.NowUnit3neededwaterandneededitquickly.Allavailablefireengineswerebeingused to pump water into Unit 1. Obtaining another off-site truck was notimmediatelypossiblebecauseroadsweretreacherous.

Fortunately, Unit 3 had an emergency cooling system that was stillfunctional: the “high-pressure coolant injection” system orHPCI (pronouncedhip-sea).Whenwaterlevelsdroppedinthecore,theHPCIautomaticallykickedin about an hour later, also drawing on battery power. Under normalcircumstances, theRCICwasused todelivermakeupwater to replace coolantboiledawaybydecayheat.TheHPCIsystem,withabouttentimestheflowrate,is designed formuch largerwater losses, such as couldoccur froma rupturedpipeorstuck-openreliefvalve.Buttheseweren’tnormalcircumstances,andtheoperatorsworked to controlHPCI flow as they had been doingwith the nowdormantRCIC.

The water level rose and pressure inside the reactor decreased. Yoshida

orderedpreparations tovent thecontainment,knowing itwasonlyamatteroftimebeforethatbecameanecessity.Hehopedtoventwhileradiationlevelsinthereactorbuildingwerelow.

The last reading of the Unit 3 water gauge, before the batteries died,indicated that the fuel might be covered by a mere sixteen inches of water.Supervisors doled out thirteen two-volt batteries from the stockpile of fiftybatteriesthathadbeendeliveredovernightfromanotherpowerstation,andthegaugewas reactivated. StabilizingUnit 3 became the priority now thatUnit 1wasbeingcooledbyseawaterinjection.

However, the HPCI pressure started to drop and the shift team at Unit 3began toworry that it could not depend on theHPCImuch longer. The teamdecided to switch to external injection, using adiesel-driven firepump,whichteammembersthoughtwouldbemorereliable.Buttodothis, theywouldfirsthavetodepressurizethereactorvesselbyremotelyopeningasafetyreliefvalve(SRV). (The reactor vessel’s pressure had to stay low enough for the low-pressurefirepumptobeabletoinjectwater.)TheshiftteamthoughtopeningtheSRVwaspossiblebecausethevalve’sindicatorlightwasoninthecontrolroom,signaling that theSRVcouldstillbeoperated from thecontrolpanel.Yoshidawasnotified,buthedidn’tthinkdealingwiththeissuewasapriorityinlightofother,morepressingcrises.

Shortlybefore3:00a.m.onMarch13,theUnit3operatorsdecidedtoshutdowntheHPCI.However,when they tried toopen theSRV, theswitchdidn’tseemtoworkandtheSRVindicatordidn’tchangefromgreentoredtoshowitwasopen.Theworkers attempted touse the firepumpanywayandpersuadedthemselvesfromasoundtheyinterpretedasflowingwaterthatitwasworking.NoneofthiswasreportedtoYoshidauntilnearly4:00a.m.Ifhehadknowninadvanceoftheplan,Yoshidaprobablywouldnothaveapprovedit:heknewthefirepumpwouldnothaveworkedwelleven if theSRVhadbeensuccessfullyopened.

After Yoshida discovered what had happened, he decided that the teamshould try to depressurize the reactor vessel manually, using scavenged carbatteries to power the valve controls, and then inject water using a higher-pressurefireenginethathadbecomeavailablefromelsewhereontheplantsitewhenaroadwascleared.Butthereactorhadalreadybeenwithoutcoolingforanhour,andithadenteredacriticalphase.AfterafinalattempttorestarttheHPCIandRCICfailedaround6:00a.m.,YoshidahadnochoicebuttoreporttoTokyothatoperatorshadlosttheabilitytoprovideemergencycoolingtoUnit3.

Althoughthereissomeuncertaintyaboutthetiming,byapproximately9:00a.m.onthemorningofMarch13,thefuelrodsbecameuncovered,triggeringthesame sequence of events that had occurred at Unit 1 some thirty-six hoursearlier: overheating of the fuel, oxidation of the fuel cladding, hydrogenformation,and releaseof fissionproducts.TheUnit3corewasmeltingdown,and the vessel pressure was rising fast. As though in a nuclear version ofGroundhog Day, workers once again faced the urgent need to vent thecontainmenttoreducepressuresotheycouldinjectmakeupwatertotrytohaltdamagetothereactorcore.

Racingagainsttime,theoperatorsattemptedtoopenthevalvesinthepipingbetweenthecontainmentandanexhauststackinordertodischargegas,buttheycouldn’t outpace the increase in pressure within the intensely hot reactor.Anotherreactornowappeareddoomed.

Three hours passed before venting got under way and the containmentpressure dropped. Because core damage had already begun, high levels ofradioactive materials were vented and radiation levels at the plant boundaryspiked.Butsoonafterward,asafetyreliefvalveopened,perhapsautomatically,anddepressurizedthereactor,allowinginjectionofanewlyuncoveredsupplyoffreshwater in fire cisterns to the core. Freshwater supplies were running low,however, andYoshida orderedworkers to prepare to switch to seawater. Justafternoon,thefreshwaterreservoirhadbeendepletedandworkersscrambledtohookuptheseawaterline.Seawaterbeganflowinginanhour.Butonceagainitwastoolittle,toolate;measurementsindicatedthatthecoreremainedexposed,asign that not enoughwaterwas getting into the reactor vessel to re-cover thefuel. Radiation levels were continuing to rise, hitting 1.2 rem (twelvemillisieverts)perhourontheUnit3sideofthesharedcontrolroom.

AcrossJapan,concernwasgrowingaboutthisdisasterthatseemedtoworsenbythe hour. Late Sunday evening, TEPCO officials held a news conference.President Shimizu, dressed in a blue company uniform, apologized to theJapanese people and said that the tsunami had “exceeded our expectations.”Withthat,hedroppedoutofpublicviewforabouttwoweeks,promptingmuchspeculationintheJapaneseandforeignmedia.(TEPCOofficialslaterexplainedthatShimizuhadfallen illbecauseofoverwork.)Shimizuapparentlyremainedinvolvedindecisionmaking,however.HeandPrimeMinisterKanwouldsoontangleoverahighlypublicizedmisunderstanding.

TEPCO corporate management likely wasn’t winning fans inside the

frenziedcommandcenteratFukushimaDaiichi, either.TapesofconversationsbetweenTokyoandthecenterrevealacertaindisconnect.

Earlier Sunday, headquarters had ordered one thousand spare car batteries,but delivery to the plant was held up for hours by delays in obtaining thegovernment permits necessary to use the expressways. By Sunday night,withthe shipment still en route andbatteries in employees’ cars and trucks alreadyappropriated,theneedfortheadditionalbatterieshadgrowncritical.About7:15p.m., an announcement blared over the public address system at FukushimaDaiichi: “Wearegoingout tobuy somebatteries,butweare shortof cash. Ifanyonecouldlendusmoney,wewouldreallyappreciateit.”

And despite his responsibilities managing the deepening crisis, Yoshida’sbossesexpectedhimtokeepupwiththepaperwork.ThepreviousnightTEPCOheadquartershadcalled theexhausted superintendentaskinghim to submithisnight shift schedules.Yoshida,whoat thatmomentwas struggling togetvitalwater into theUnit 1 reactor, responded: “I’m a bit too beat to prepare themnow.” Headquarters persisted and Yoshida eventually replied, “[N]one of ourworkerscangohomeanyway.It’sjustaquestionofwhethertheyareawakeorasleep.”Whether thatsatisfied the timekeepersatheadquarters isunknown;bythetimeYoshidarespondedtothem,theyhadallgonehomeforthenight.

Back in the United States, it was early Sunday morning when the NRC’semergency operations center received a call from Admiral Kirkland Donald,director of naval reactors at the National Nuclear Security Administration, asemiautonomousdivisionoftheDOE.DonaldwantedtonotifytheNRCandtheDOE,whichjoinedthecall, thattheU.S.S.RonaldReagan,anuclear-poweredaircraftcarrieroffthecoastofJapan,had“pickedupsomeactivityoutatseathatwethinkyouneedtobeawareofandprobablyneedtobeaddressingwiththeJapanesegovernment.”The“activity”wasradiation.

TheRonaldReaganandsixothernavyvessels fromtheSeventhFleethadbeenenroute toSouthKorea toparticipate in jointnavalactivities therewhentheywere diverted to Japan after the earthquake to help in relief efforts. Theships had taken up position about one hundred nautical miles off FukushimaDaiichi,with theofficers thinking theywouldbeoutside any radiationplume.ThenradiationdetectorsintheRonaldReagan’sengineroompickedupreadingstwoandahalftimesnormal.

Radiation was also detected on crew members and helicopters that hadlanded on a Japanese ship fifty miles offshore from the plant. Although the

levelswere low, theadmiralwasworried.Themeasurementswerehigher thanthenavyhadexpected,basedon the scant informationavailable.TheprospectthatU.S.personnelmightbeatriskbecamereal.(Thereweremorethan3,400sailorsandaviatorsontheRonaldReaganalone.)Thecrewandequipmentweredecontaminated and the navy ships headed for safer water about 130 nauticalmilesoffshore.Enroute,theRonaldReagancontinuedtodetectcontamination.

For the navyvessels, getting out of harm’swaywas amatter ofweighinganchorandmovingfartherouttosea.Itwouldnotbeassimpleforthetensofthousands of Americans living in Japan. They no doubt were beginning towonderwhethertheyweresafeandwheretheycouldgoiftheyweren’t.

Approximately 160,000U.S. citizenswere living in Japan inMarch 2011.Responsibilityfortheirwell-beingrestedwiththeU.S.EmbassyinTokyo.U.S.ambassadorJohnV.RooshadputoutacalltoWashingtonforguidancealmostimmediatelyaftertheearthquakeandtsunami;soontheembassywasalsocaughtup in responding to a nuclear accident. The Japanese were not providinginformationandrelationsweregrowingstrained.

TheNRCscrambledtogetoneofitsexpertsaboardamilitaryflightabouttodepartforJapanlateontheeveningofMarch11.ItwassuchahastydeparturethatAnthonyUlses,thechiefoftheNRC’sreactorsystemsbranch,hadnotimeto pack. ByMarch 14, a total of elevenNRC experts had been dispatched toJapan.

Itwasthatsameday,March14,thattheJapaneserelentedandacceptedtheU.S.offerofassistance,andasa resultmoresystematicdatacollectionbegan.TheNationalNuclearSecurityAdministrationsentthirty-threepeopleandeighttons of equipment that are part of its AerialMonitoring System (AMS). TheAMS uses specially equipped aircraft to identify andmeasure radiation in anemergency.Eventually,aU.S.GlobalHawkdronewentaloftover thereactorsto begin gathering data and images that were shared with the Japanesegovernment.

On the morning of March 14, radiation levels at monitoring posts aroundFukushima Daiichi were high, and the drywell pressure in Unit 3 was againstartingtorise.Workershadsuccessfullyventedthecontainmentthreetimestheday before—or at least thought they had—and now needed to do so again.Althoughtheymanagedtogetpowerandcompressedairtothenecessaryvalvesby using a portable generator, the drywell pressure continued to increase.Thecrewwasawarethattherehadbeenagapofmorethanfivehoursbetweenthe

timeitshutdowntheHPCIandthetimeitmanagedtosetupthefireenginetoinjectwaterintothecore:morethanenoughtimeforsignificantcoredamagetooccur.

Even worse, although water was being pumped into the reactor, the levelinsidedidnotappear tobe rising.Noonehadknownforquitesome time justhow much water had been getting into the reactor vessel, because of theintermittent operating histories of RCIC, HPCI, and the fire engine.WorkersfearedthatUnit3mightnowbefollowingatrajectorysimilartothatofUnit1.Meanwhile,anothercrisiswasabouttoemergeinanunexpectedplace.

While plant personnel focused on cooling the three reactors that had beenoperating when the earthquake struck, trouble was slowly brewing in one ofthosethathadbeenshutdownonMarch11.InthespentfuelpoolofUnit4,thewater temperaturewas steadily rising, inching toward theboilingpoint.At thetimeoftheearthquake,Unit4hadbeenoutofserviceformaintenance,andtheentire reactor core was sitting in the spent fuel pool, high above the reactorvessel. Consequently, the fuel pool was loaded with more than 1,500 fuelassemblies.Morethanone-thirdofthespentfuelassemblieshadbeenremovedfromthecorejustthreemonthsearlier,meaningtheywerestillrelatively“hot”intermsofbothtemperatureandradiationlevels.Ofthesevenspentfuelpoolsat Fukushima Daiichi—one for each reactor plus a common pool for extrastorage—theUnit4poolhadthehighestheatloadbyfar.

Thespentfuelpoolsarebigtanksofwater,forty-fivefeet(fourteenmeters)deep, with walls and floor made of reinforced concrete and lined with steel.Spent fuel assemblies are stored in racks in the lower third of the pools. Thelargevolumeofwaterabovetheracksprovidesradiationshielding.Withoutthewatertoprovideshielding,theradiationlevelevenattherimofthepoolwouldbequicklylethaltoworkers.Becausespentfuelgeneratesheatandhighlevelsofradioactivity for many decades after discharge from a reactor, active coolingsystemsarecritical.Duringnormaloperation,pumpscirculatewatertomaintainapooltemperatureofabout100°F(40°C).Oncecoolingisinterrupted,thewaterinthepoolwillbegintoheatup,andifitshouldreachtheboilingpointlossescanmountrapidly.

ThespentfuelpoolsatUnits1through4hadbeenwithoutpowertocirculatecooling water for almost three days. Yet until now operators had paid littleattention to them. For decades, engineers believed that spent fuel pools posedmuch less safety risk than operating reactors and hence required far lessprotection. Compared to fuel assemblies in an operating reactor core, most

assemblies stored in spent fuel pools are cooler and less radioactive, becausetheyhavebeenoutofareactorforyearsandtheirshorter-livedfissionproductshavedecayedaway.Ifaspentfuelpoolweretolosecooling,operatorstypicallywould have days to respond before the massive volume of water in the poolcould heat up enough to boil and eventually uncover the fuel. More severescenarios—suchasamassiveearthquakethatmightdamagetheintegrityofthepoolstructureitself—wereregardedastooimprobabletoworryabout.

Thislackadaisicalattitudeinformedthewayspentfuelpoolsweredesignedandbuilt.Regulators in theUnitedStatesandelsewherewhoreviewedboilingwater reactordesignsdidnot require that the spent fuel cooling systemsbe asrobust as those for the reactor core. Nor did they require that the pools besurroundedbyleak-tight,pressure-resistantcontainmentstructuressuchasthosemandatedforthecores.And,inapprovingGE’sMarkIandIIreactordesigns,theregulatorssawnoprobleminhavingthespentfuelpoolperchedonthefifthfloorofthereactorbuildingandtoppedonlybyasteelframestructure,despitetheobviousdangerssuchanarrangementmightposeinaseriousaccident.6

Thesafetyofthesepooldesignswaspredicatedontheabilityofoperatorstorestore cooling within a few days. Apparently little thought was given to thequestionofwhatwouldhappeniftheycouldn’trespondpromptly—say,iftheywere occupied with a prolonged loss of power and three reactor meltdownssimultaneously.Neitherdidthedesignersorregulatorsworrymuchaboutwhatwould happen if the operators didn’t have as much time to act as everyoneassumed—for instance, if a large earthquake caused the pool to losewater bysloshingitoverthesidesorcrackingthelinerandcausingittoleak.

Whatcouldhappen is this: if thewater leveldiddecreaseanduncover thefuelrods,theycouldoverheatandmelt,muchlikethoseinsidethereactor—butwithonecriticaldifference.Thespentfuelisnotenclosedbytherobustprimarycontainment.

Eventhoughtheamountofheatinaspentfuelpoolisfarlowerthanthatinareactor,thezirconiumalloycladdingencasingthehottestrodscancatchfireifitreaches a temperature of 800°–900°C, generating its own heat source. This inturncould rapidlydamage the fuelpellets themselves andallow the releaseofgaseous isotopes, like the long-livedcesium-137.Under certain circumstances,such a fire could spread to other assemblies in the pool. And because typicalspentfuelpoolsholdmorefuelthanasinglereactorcore,afirethatinvolvedtheentirepoolcouldreleasemorecesium-137thanareactormeltdown.(Iodine-131,

anothermajorisotopeofconcerninareactoraccident,posesmuchlessriskinaspentfuelpool.Itwouldnotbepresentinsignificantamountsunlessthefuelinthepoolwas less than threemonthsold; after that time, the iodine-131wouldlargelyhavedecayed.)Andfinally,reactionofthezirconiumwithsteamwouldproduceexplosivehydrogengas, just as it did in thedamaged reactor cores atFukushimaDaiichi.

At that point, the only barrier between these isotopes and the environmentwould be the leaky, flimsy top of the reactor building. Such a structure hadalreadyproventobenomatchforthehydrogenexplosionthatoccurredatUnit1.Whenthathappened,radiationlevelsdidnotincreaseverymuchbecausetheprimary containment inside the building remained intact. But a hydrogenexplosionresultingfromaspentfuelfireatUnit4’sspentfuelpool,occurringina largely uncontained environment, would release a catastrophic amount ofradiation.

By the time operators began to focus on ways to cope with the risingtemperatureintheUnit4pool,theradiationleveltherewasalreadysohighthatitprecludedanyhumaninterventiontogetwaterintothepoolusingtemporarypumps.Astheybegantoexploreotherapproaches,theoperatorsknewtimewasagainstthem.

But on thisMondaymorning,March 14, the next explosion to hit FukushimaDaiichicamenotfromUnit4,butfromUnit3.At11:00a.m.,ahugeblastblewoutnotjusttheuppersectionsofthereactorbuilding,ashadhappenedatUnit1,butalsolargesectionsofthewalls,injuringanumberofpeoplenearby.Debrisfell into theUnit3spent fuelpoolandonto theground,where itdamaged thefireengineandhosespositionedtoinjectseawaterintothereactor.Onceagain,hoursofpainstakingworkwereundoneinaninstant.

SmokepoursfromUnit3followingablastat11a.m.onMarch14.Fallingdebrisinjuredworkersontheground and damaged firefighting equipment thatwas being readied to inject vital coolingwater into thereactor.TokyoElectricPowerCompany

By early afternoon, radiation levels above thirty rem (three hundredmillisieverts)perhourweredetected justnorthofUnit3, raisingconcerns thatthe core had alreadyundergone significant damage and that the explosionhaddispersedradioactivematerialaroundthesite.Therisingradiationalsorenderedpart of the Units 3 and 4 control room unsafe, further hampering operators’abilitytogaugetheconditionofthereactor.

Compared to the seriously damagedUnits 1 and 3,Unit 2 had seemed like asuccessstory.IncontrasttoUnit3,theRCICatUnit2hadapparentlycontinuedto operate on its own for nearly three days, keeping the water level fromdropping and exposing the core. This was remarkable, because ordinarily theRCICshouldnothavebeenabletooperateforthatlongwithoutbatterypower.Butoperatorsknewitcouldn’tkeeprunningindefinitely.

TheRCICtransferredheatfromthereactorvesseltothetorus,butthatheatremainedwithinthecontainment,whichitselfwasalreadyoverheated.Withoutany means of external cooling, pressure and temperature in the containmentcontinuedtoincrease.TheRCIChadnotbeendesignedtofunctionundersuchpunishingconditions.Andataround1:30p.m.onMarch14,itlookedlikeithadfinallyquit.TheUnit2waterlevelstartedtodrop.Nowitwasclearthat,withoutpromptaction,Unit2wouldsufferthesamefateasUnits1and3.

Forexhaustedshiftoperators,someofwhomhadbeenondutyforthreedayswithoutsleep,thecrisesseemedtohavenoend.Theoperatorsneededtoinjectwater into theUnit 2 reactor vessel as soon as possible to keep the core frombeing exposed. But just as at Units 1 and 3, they first needed to vent thecontainment. Otherwise, they would not be able to depressurize the reactorvessel adequately to force water into it with the fire engines. Yoshida hadanticipated this eventuality right after the Unit 1 explosion and had orderedworkerstopreparethemeansbothtoventtheUnit2containmentandtoinjectwaterintoitwhenneeded.

ButYoshidahadnotanticipatedtheUnit3explosion,whichdisruptedboththe Unit 2 containment vent line and the alternate water injection line thatworkershadestablished.Thissetbackmarkedthethirdstrikeagainstthedoomedplant.Workingamidrubble,aftershocksfromtheearthquake,andhighradiationlevels,acrewracedagainsttimetorepairthedamagetotheUnit2ventlineandtoconstructanewwaterinjectionline.Workerstriedtoventthecontainmentat4:00p.m.but failed.Meanwhile, thewater level inside the reactorvessel keptdropping.By4:30,thetopofthecorewasexposed.

TEPCO president Shimizu ordered Yoshida to try to inject water into thereactorvesselwithoutwaitingforventingtosucceed.Buttomaketheattempt,workers needed to open a safety relief valve thatwouldmove steam from thereactor vessel into the torus. Efforts to open the valvewere complicated by alackofbatterypower. (Thisreliefvalve isdifferent fromthecontainmentventvalvesthatworkersstruggledwithonUnits1and3.)7

Onceagain,asearchwasmountedforbatteriestoenergizethesafetyreliefvalve. Thesewere carried to the control room and connected, but they lackedenoughvoltage.Thewaterlevelcontinuedtodrop.Finally,atabout6:00p.m.,additionalbatteriesallowed thevalve tobeopened.But thewaterwasnowsolow it didn’t even register on the gauge, meaning that the core might becompletelyuncovered.Alsoworrisomewasthefactthat,althoughhydrogenandradioactive gases were flowing into the containment, pressure there was notrising,asithadintheotherunits.Thecontainmentpossiblyhadsprungaleak,allowing gases to escape into the reactor building and out through the holeblowninthesideofthebuildingwhenUnit1hadexploded.

By7:00p.m.,pressureinsidetheUnit2reactorhaddroppedfarenoughforthe fire engine pump to force water into the core. But a passing workerdiscovered that the fire engine, which had been idling while awaiting the

injectionoperation,hadrunoutoffuel.Theenginewasrestartedshortlybefore8:00 p.m., but water levels in the core remained too low to measure. Soonpressure inside the reactor rose again, thwarting the fire engine pump. Theintense heat from the exposed fuel was quickly vaporizing the water beinginjected.Assteamrefilledthereactorvessel, thepressure increased.Toenablethepump to injectwater again, theoperatorsmanaged toopena second reliefvalve.Thatappeared todo the trick;water inchedup tocoverpartof thefuel.Buttheprogresscameatacost:steampressureinsidethereactorwasontherisetoo.For thenextseveralhours, theoperatorsplayedcatandmousewithwaterlevel and pressure. The steam pressure periodically spiked above the waterpressure of the fire engine hoses, and the operators could not be certain howmuchwaterwasgettingintothereactorvessel.

At thesame time,operatorswere tryingwithoutsuccess tovent theUnit2containment.Accordingtothegaugereadings,bynowthecontainmentpressureshouldhaveforcedtheventopenbyblowingthrougharupturedisk,butithadnot.Thepressureinthedrywellsuddenlybegantoriserapidly,andYoshidawasafraid it would burst. He decided it was necessary to try to vent the drywelldirectly—an action that was considered a last resort because it would allowradioactive gases to escape into the environment without first being filteredthroughthewaterinthetorus.However,forbetterorworse,operatorswerenotabletoventthedrywelleither.

TheoperatorscontinuedtostrugglethroughtheearlyhoursofMarch15tofindaway tovent thecontainment.At6:00a.m., just asa shift change in theUnits 3 and 4 control room was taking place, a noise that sounded like anexplosion was heard in the area around the torus beneath the Unit 2 reactorvessel.Pressureinthetorusdropped,suggestingthattheexplosionhaddamagedthe torus and allowed its contents to escape into the reactor building. If thecontainmenthad actuallybeenbreached, vast amountsof radiation could soonspilloutintotheenvironment.

Then,aroundthesametime,ahydrogenexplosionrippedthroughtheUnit4reactor building, collapsing the top two stories of the five-story structure.Theincoming and outgoing control room crews fled to the safety of the SeismicIsolationBuilding, retracing their route on foot this time because the concreteandrubblecovering thegroundnear thereactormadecar travel impossible. Intheir cumbersome radiation suits andbreathingequipment, it took themnearlytwohourstomaketheirwaytothebuildingandalertYoshidaofthedamagetoUnit4.

Atabout6:20a.m.onMarch15,ahugeexplosion ripsapart the top twostoriesofUnit4,exposing thespentfuelpool.Untilthen,Unit4hadseemedtoposetheleastthreatinthefirstdaysoftheaccident.TokyoElectricPowerCompany

TheworkersatFukushimahadexperiencedmanysurprises in thepast fewdays,buttheexplosionatUnit4musthavecomeasaparticularshock.Althoughthey were aware that the temperature was rising in the spent fuel pool, theybelieved thatUnit 4was the least of their problems.Now it appeared that thepoolhadheatedupmuchfasterthantheyhadexpected,sorapidlyinfactthatthespent fuel might have become uncovered, sustained damage, and generatedexplosivehydrogen.Butevenmoreworrisomewastherealizationthattheotherspentfuelpoolsatthesitemightalsobeinjeopardy—aparticularconcerngiventhatthepoolsatUnits1and3werenowdirectlyexposedtotheenvironment.Inaninstant,thespentfuelpoolswentfrombeingalowprioritytoanimmediatethreat.

Inresponsetothedeterioratingsituation,at11:00a.m.PrimeMinisterKanordered residents between about twelve and eighteen miles (twenty to thirtykilometers)ofthereactortoremainindoors.Thosewhohadn’talreadyflednowbecamehousebound, relyingon their small framehomes toprotect them fromwhatevermighthappennext,andnotknowingwhentheymightbeallowedoutagain.Noonehadeverwarnedthemtoprepareforasituationlikethis.

WiththecatastrophiceventsatFukushimaDaiichishowingnosignofslowing,the radiation exposure levels of the workers grappling with the disaster had

beguntoworrygovernmentandutilityofficialsinTokyo.Thegovernmentcameupwithasolution:increasetheallowablelimitsofexposure.

On March 14, the government agreed to raise the maximum allowableradiationdoseforworkersinanemergencyfromtenrem(100millisieverts)peryeartotwenty-fiverem(250millisieverts)peryear.Thedecision,announcedthefollowing day, was based, in part, on fear that soon everyone at FukushimaDaiichimightexceedtheexistingexposurelimitandthusberequiredtoleave.Alreadyworkershadtoperformtasksinshortbursts tostaywithincumulativedoselimits.8

That evening, TEPCO president Shimizu was told that, because of theworsening conditions, Yoshida was considering evacuating about 650nonessential personnel from the plant. Shimizu telephoned the head of NISAbeforedawnonMarch15toapprisehimofthegraveconditionsatUnit2andnoted that if things continued to worsen, the company might pull out somepersonnel. In another instance of bungled communication, Shimizu apparentlydidnotmakeitclearthatessentialworkerswouldremain.

Officials in the prime minister’s office feared a total abandonment of theplant,inwhichcasethedangerswouldgrowexponentially.Ataround4:00a.m.,anangryKansummonedShimizutohisoffice,wheretheutilitychieftoldhimtherewasnoplantoabandontheplant.(ThemediareportedthatKan,iratethathewasnotinformedofeventsattheplant,shoutedatShimizu,“Whatthehellisgoingon?”)TheencounterapparentlyconvincedbothKanandShimizuthatthelinesofcommunication—andcooperation—neededtoimprovequickly.Thetwomenagreedtoestablishagovernment-TEPCOintegratedresponsecenterattheutilityheadquarters.

Aboutninetyminuteslater,KanvisitedTEPCOheadquarterstomakeitclearthat thegovernmentwas asserting a stronger role in the accident response.Enroute, he said later, he considered aworst-case scenario inwhich evacuationscouldextendasfarasmetropolitanTokyo,population13million.(Indeed,massevacuationsmight have been necessary, according to a worst-case assessmentprepared at Kan’s request by the chairman of the Japan Atomic EnergyCommissionandpresentedtotheprimeministeronMarch25.)

The TEPCO showdown coincided with the arrival of the latest bad newsfromFukushimaDaiichi:thepossiblecontainmentruptureatUnit2,followedbytheblastintheUnit4spentfuelpool.

WhentheJapanesefinallydidaskforhelpfromtheUnitedStatesonMarch14,they were looking for heavy-duty pumping equipment that could deliverseawater topits fromwhich itcould thenbe injected into the reactorcoresviafireengines.U.S.militaryforcesinJapanhadfirefightingequipmentthatwouldfitthebill,anddiscussionsalreadywereunderwaywithTEPCO.

Overthecourseofthatday,NRCstaffersbeganarrivinginTokyo,includingTonyUlses and JimTrapp,both experts inboilingwater reactors.Finally, theNRC’s emergency operations center atWhite Flint had eyes and ears on theground.TheNRCteamjoinedexpertsarrivingfromothergovernmentagencies,mostofthembasedattheU.S.Embassy.

Later onMonday, JackGrobe, theNRC’s deputy director for engineering,was manning the White Flint Operations Center when Chairman Jaczkotelephoned for anupdate.Grobehadworrisomenews: theprevailingwinds inJapan,whichhadbeencarrying radiationout to sea,wereabout to shift to thesouthwest—towardTokyo.WiththreereactorsandtheUnit4spentfuelpoolintrouble,“thatchanges thedynamicof theprotectivemeasuresaspectsof this,”Grobe told his boss. Vast numbers of people could now be downwind. As aresult,theOperationsCenterhadsummonedadditionalstaffexpertsonradiationdoseassessmentsandmeteorology.Butsofar,GrobetoldJaczko,Japan’s12.4-mile (twenty-kilometer) evacuation zone around Fukushima Daiichi was“consistentwithwhatwewouldrecommend.”

MartyVirgilio thencalledGrobe to tellhimU.S.nuclear industryofficialsnowspeculated that therewasacrackin the torusatUnit2. If true, thiscoulddramaticallychangetheteam’sassessmentofthesituation.Thetoruswaspartoftheprimarycontainment.Uptothattime,asbadasthingshadgotten,theNRCwasnotawareofevidencethattheprimarycontainmentsatanyofthereactorshadexperiencedamajorrupture.Suchabreachcouldreleasedozensoftimesasmuch radioactivematerial as theminor leakage that had previously occurred.Given theprojectedwindshift inland,aUnit2containment failurecouldhavecatastrophicconsequencesforalargesegmentoftheJapanesepopulation.

“Imean, this isbeginning to feel likeanemergencydrillwhereeverythinggoeswrongandyoucan’t,youknow,youcan’timaginehowthesethings,allofthem,cangowrong,”saidGrobe.Nodrillhadevercomeclosetothis.

But the bad news hadn’t stopped arriving. JimTrapp called to say that anadmiralattheU.S.navalbaseatYokosuka,southofTokyoand188milesfromFukushimaDaiichi,wasreportingradiationmeasurementsof1.5millirem(0.015millisievert)perhour,apparentlybecauseofthewindshift.TheNRCteamwas

astonishedthatsuchahighdoseratewouldbedetectedatsuchagreatdistancefromtheplant.

Trapp added onemore ominous bit of information from Japanese officialsabout the blast inside Unit 2: “[T]hey do believe they breached the primarycontainment.”TonyUlses, alsoon thephone, raisedanevenmore frighteningprospect: the loudnoiseheardinUnit2“wasprobablywhenthecorewentX-up”—meaning when it had melted through the bottom of the reactor vessel.“Landing in the water under the vessel, it would have caused a little steamexplosion,”saidUlses.

“Believeitornot,Jack,we’retellingyouthegoodnews,”TrapptoldGrobe.Thenhelaunchedanotherdirelitany,basedoninformationgleanedfromNISAofficialsinTokyo.NoonewascertainofthewaterlevelinthespentfuelpoolatUnit3;asaresultoftheexplosion,thereactorbuilding“reallycollapsedintothefuelpool.”Radiationoftenrem(onehundredmillisieverts)perhourwasbeingmeasurednearUnit4,whichcouldprovelethalafteradayortwoofexposure.(For context,workers atU.S. nuclear reactors are limited to five remperyearandgenerallyreceivefarlessthanthat.)

In an attempt to find some good news to pass along to his exhaustedcolleagues in Tokyo, Grobe told Trapp and Ulses that additional NRC staffmembers were en route. But that prompted a word of warning from Trapp:“[W]e’vegottothinkabout...whetherwewantthemtocome.”

“Imean,” addedUlses,”we’re getting to the pointwhere this is justmorebodiestohavetogetbackoutofherepossibly.”

4

MARCH15THROUGH18,2011:“IT’SGOINGTOGETWORSE...”

Jim Trapp and Tony Ulses were back on the phone with their colleagues atWhiteFlintbeforedawnEastCoasttimeonMarch15.Theoriginalplanforthepair to spell each other off until reinforcements arrived had fallen apart; therewas just toomuchgoingon.Bothwereexhausted; ithadbeena roller-coasterday.

At first, ithadseemed that the floodofbadnews fromFukushimaDaiichiwas slowing.The latestpressure readings indicated that thecoreof theUnit2reactor had not breached the reactor vessel, and operators were able toreestablishwaterinjection.Otherpressurereadingscontradictedtheassumptionthat the mysterious noise heard at Unit 2 had been a rupture of the torus,although the data were inconsistent, suggesting an instrument failure. Units 1and3werestable,withseawaterinjectionsproceedingsmoothly.

The details even elicited a bit of optimism fromBrianMcDermott a shorttime laterwhenhebriefedhisboss,Gregory Jaczko. “[L]astnightwe thoughtwehadabigproblem,”hetoldJaczko,referringtoUnit2.“Andthismorning,it,itsuggestswehavelessofaproblem.”

Thatassessmentwasshort-lived.Overnight,concernaboutthestatusofUnit2hadledtheNRC’sProtective

MeasuresTeam to run computer simulations for that unit basedonworst-caseassumptions: a fullymolten core and a ruptured containment.The simulationsprojected levels of radiation exposure based on the prevailing winds blowingtowardTokyo.Readingspickedup at theYokosukanaval base and elsewhereseemedtosuggestthatthereleasewasworsethaneveryonehadthought.

Because the NRC’s RASCAL program can only estimate radiation doses

within fiftymiles of a release site, itwas of little use in interpreting the datacollected at Yokosuka, about 190miles from the plant. Even so, the findingswerepassedalongtotheStateDepartmentandtheU.S.EmbassyinJapan.Thecalculationsindicatedthat,ifwindscontinuedtoblowsteadilyinonedirection,thenevacuationwouldbewarrantedforeveryoneuptofiftymilesdownwindoftheplant.ThiswasbasedontheU.S.EnvironmentalProtectionAgency’s(EPA)protective action guides, or PAGs. (According to the PAGs, members of thepublic shouldbeevacuated fromanyareawhere theycould receivemore thanonerem,ortenmillisieverts,ofradiationexposureinafour-dayperiod.)Basedon the RASCAL estimate, the NRC was recommending to State that U.S.citizens evacuate if they were within fifty miles of the plant, four times thedistance the Japanese were recommending. Approximately three hundredAmericans resided inside this fifty-mile zone, along with about 2 millionJapanese.

From a health standpoint, it seemed a prudent call. Politically, however, arecommendationsoatoddswithwhatJapanwastellingitscitizenswassuretoupsetTokyo.TheStateDepartmentwasinanawkwardpositiondiplomatically,hopingtheNRCmightfindawaytosupportthetwelve-mileevacuationwithapress release—even suggesting the language it wanted the NRC to use,reaffirmingtheJapaneseevacuationrecommendations.TheNRC’sexpertsstuckbytheirguns:askJapantotelluswhywe’rewrong,theycountered.

For the NRC, a fifty-mile evacuation advisory for Japan could also havepolitical ramifications at home. The commission currently requires thatemergencyevacuationplansbedevelopedonlyfortheareawithintenmilesofanuclear reactor.Safelyevacuatinganarea twenty-five timesas largewouldbedifficult, if not impossible, at many reactor sites without detailed advancepreparation—andplentyoftime.

While debate continued about the status of FukushimaDaiichi Unit 2 and itsimplications,TrappandUlseshadmorebadnewstoreport:thecrisisattheUnit4 spent fuel pool. It appeared, they said, that the situation could be just asdangerous—andbaffling—asthatinUnit2,ifnotmoreso.

ThehydrogenexplosionatUnit4hadoccurredalmostsimultaneouslywiththesuspectedexplosion inUnit2 (about6:00a.m.March15, Japan time),buttheNRCheardnothingaboutaproblematUnit4untilacoupleofhoursafterthe report of a possible containment breach atUnit 2. (MasaoYoshida at theplant also had been late in learning. He had not known of the explosion for

almost two hours—until his workers made it back to the Seismic IsolationBuilding.)TheUnit 4 reactor, out of servicewith its fuel in thepool, hadnoteven been on anyone’s radar. In fact, only a few hours before the Unit 4explosion,MartyVirgilio had reported in a status briefing that therewere noconcernsaboutanyofthespentfuelpools,althoughgiventheextendedlossofpower,theteamneededto“keepaneyeon”them.EvenafterinformationabouttheUnit4crisisbegantricklingin,Unit2remainedatthetopoftheprioritylist—butnotforlong.

As the NRC staffers pieced together data from a variety of sources, adisturbing picture began to emerge that challenged the team’s complacencytoward the spent fuel pools. Themassive blast that had blown off theUnit 4reactor building’s roof and damaged walls there looked like yet anotherhydrogenexplosion.Butwherehadthehydrogencomefrom?Themostobvioussourcewouldbeachemicalreactionbetweensteamandoverheatingfuelrodsinthe spent fuel pool. But thatwouldmean that thewater level had dropped toexposethefuelmuchmorequicklythananyoneanticipated.

The spent fuel pool was designed to hold 1,300 to 1,400 tons of water,approximatelyhalfthevolumeofanOlympic-sizedswimmingpool.Ifthepoollost cooling, it would have taken a couple of days for the water to reach theboilingpoint.Whenthewaterbeganboilingaway, thepoolwouldlosearoundonehundredtonsofitperday.Aboutonethousandtonsofwaterwouldhavetoboil off before the fuel would be exposed. By a back-of-the-envelopecalculation,itshouldtakewelloveraweektogettothatpoint.Atthetimeoftheexplosion,thecoolingpumpsfortheUnit4poolhadlackedpowerforlessthanfour days. If the spent fuel had become uncovered in such a short time, thenmore thaneighthundred tonsofwatermusthavebeen lost insomewayotherthan boiling. This could have been a result of shaking during the earthquake.(OneworkerwhowasontheUnit4refuelingfloorwhenthequakestrucklaterreported seeing waves in the pool and being drenched as water sloshed out.)Therewasanotherpossibility: a leakor crack in thepool itself, causedby theearthquakeortheexplosioninUnit3.

NoonecouldverifywhatwasactuallygoingoninUnit4,orinanyoftheother spent fuel pools for that matter, because the gauges that measured thewaterlevelandtemperatureinthepoolswereuselesswithoutelectricalpower.

Theworst case seemed to be confirmedwhen theNRC started to receivereportsthatafewhoursaftertheblastafirewasobservedburningintheUnit4reactor building. Initial fearswere that this showed the zirconiumcladdingon

the fuel had indeed ignited,making it possible that the fuel itselfwasmeltingandreleasingamassiveamountofradioactivecesium.Withtheroofandwallsof theUnit4reactorbuildingblownapart, theradiationwouldgostraight intotheatmosphere.Noonecouldgetcloseenoughtoinvestigate;however,thefireburneditselfoutshortlybeforenoon.ItssourcewassubsequentlyidentifiedbyNISAaslubricatingoilusedinageneratoronalevelbelowthefuelpool.Thequakemighthavedamagedpipingorastoragetank,andasparkapparentlysettheoilablaze.If thezirconiumcladdinghadbeenburning,thefirewouldhavelastedfordays.

Radiation measurements between the Units 3 and 4 reactor buildings hadsoared to forty rem per hour, making even brief forays near the buildingsextremely dangerous.They also seemed to indicate that, even if there had notbeenazirconiumfireintheUnit4spentfuelpool,somethingbadhadhappenedthere:perhapspiecesofspentfuelhadbeendispersedbytheexplosion,ortherewasnowaterleftinthepooltoshieldthefuel.

Meanwhile, in the hours after the mysterious event at Unit 2 and theexplosion atUnit 4, radiation at the plant gate had spiked to its highest levelsince the accident began, and an ominous cloud of “white smoke” was seendrifting from Unit 2. The prevailing winds continued blowing inland, towardpopulated areas. News that the wind direction was rotating clockwise, awayfrom Tokyo but toward smaller cities and agricultural areas northwest of theplant,wassmallconsolation.Sinceitwasnolongerclearthattherehadbeenacontainment rupture atUnit 2, reports ofwhite smoke notwithstanding, itwaslookingmoreplausiblethatUnit4wasthesourceoftheincreasedemissions.

NowtheNRChadanewchallenge:tryingtounderstandwhatwasgoingonwiththeUnit4spentfuelpool.Thequestionofwhetherthepoolstillheldanywater had serious implications for estimating the amount of radiation thatpotentially could be released. Thiswould soon become a thorny issue for theNRCteam.

TherewasnodoubtatWhiteFlintthatwaterhadtobeaddedtotheUnit4poolimmediately.Thatmeantplantoperatorswouldhavetofigureoutawaytodelivertonsofwaterperhourintoaspentfuelpoolfivestoriesofftheground,filledwith rubble, and emitting levels of radiation that could be lethal withinminutes. In the NRC’s view, getting water into the spent fuel pools shouldbecome thenumberonepriorityatFukushimaDaiichi.However, the Japanesedidnotyetseeitthatway.

WHEREFUKUSHIMADAIICHIGOTTHINGSRIGHT

FukushimaDaiichi focusedworld attention on spent fuel pools and theirassociatedrisks.Fukushimaalsodemonstratedasafermeansofmanagingthespentfuelrisk:drystorage.

There were 408 spent fuel assemblies in dry storage at Fukushima.Although jostled by the earthquake and submerged temporarily by thetsunami, these assemblies survived without the need for helicoptersdroppingwaterfromaboveorfiretruckssprayingwaterfrombelow.

Damage inside the dry cask storage building at Fukushima Daiichi was extensive. Although thecasks(oneisvisible,center)werejostledandsubmergedbythetsunami,theyremainedunharmed.TokyoElectricPowerCompany

Drystoragewasfirstusedin theUnitedStates in1986,andit isnowpracticed at plants across the country. After spent fuel assemblies havestayedinapoolforaninitialperiod,workerstransferthemintodrystorageon-site.Typically,aboutfifteentonsofspentfuelareplacedinsideasealedmetalcanister, thenplacedwithinaconcreteandsteelcask(thecoreatalargereactorholdsnearlyonehundredtonsoffuel).Passivecooling—airflowfromthechimneyeffect—removestheheatproducedbythefuel.

Passivecoolingdoesnotworkfordenselypackedspentfuelpools.Theheatproducedby thefuelassemblies—particularly thosedischargedfrom

the reactor corewithin thepast fiveyears—requires continual coolingofthewaterinthepools.

A large radiation release from a pool could result in thousands ofcancerdeathsandhundredsofbillionsofdollarsindecontaminationcostsandeconomicdamage.

The crowded spent fuel pools at U.S. reactors pose hazards. Anaccident or terrorist attack could cause a loss of water from a pool orinterruptvitalcoolingsystems.AsFukushimaDaiichidemonstrated,itcanbechallengingtopumpwaterupfivelevelsintoapoolforaboilingwaterreactor.Andunlessahydrogenexplosionripsapartwallsandroofs,itcanbedifficulttodropwaterintoapoolfromaboveorspraywaterinfromtheside.

Transferring more assemblies into dry storage is the better way tomanagerisksposedbyspentfuel.Reducingthespentfuelpoolinventoryaccomplishesfourthings:It(1)reducestheheatloadinthepool,(2)addsmore water to the pool for every assembly removed, (3) allows theremaining assemblies to be spread out, and (4) reduces the amount ofradioactivematerialinthepool.

Thefirsttwoofthesegiveworkersmoretimetointerveneintheeventofaproblem,increasingtheirchancesofsuccess.Thethirdrestoresmarginagainst inadvertent criticality within a spent fuel pool and providesadditionalspacebetweenassembliesforcoolingairorwaterflow.Andthefourth limits the sizeof the radioactive cloud that canbe emitted fromapool.Thus,boththeprobabilityandtheconsequencesofaspentfuelpoolaccidentareloweredbymovingfuelassembliesintodrystorage.

Thereare lessons tobe learnedfromwhatwentwrongatFukushima.Thereareequallyimportantlessonstobelearnedfromwhatwentright.

NRC chairman Gregory Jaczko checked in with the Operations Center atWhiteFlintataround9:00p.m.onMarch15.JackGrobewasondutyandgavehisboss a rundown.FreshNRC troopsweredue to arrive in Japan toproviderelieftoJimTrappandTonyUlses.(Bynow,abouttwohundredpeoplefromavarietyoffederalagencieshadarrivedattheU.S.EmbassyinTokyotoassist.)

Reliable informationwasstillhard tocomeby,Grobe toldJaczko,and theNRC was relying on “snippets” of information from NISA and U.S. and

Japanesenewsmedia.“It’sbeenextremelyfrustrating,”Grobesaid,addingthathe hoped to gleanmore from industry sources in theUnited States.Also, theDOE’s Radiological Assistance Program teams were now on the ground andwould soonbeprovidingcrucial landandaerialmonitoring.That,Grobe said,“willbeahugebenefit.”

JaczkoremindedGrobethatitwouldtakeatleasttwohourstoobtainhigh-levelauthorizationifanexpandedevacuationorderforU.S.citizenswasdeemednecessary. “I don’t anticipate a need for that,”Grobe told his boss. “[T]hingsseemtobereasonablystable.”

JaczkowasdueonCapitolHill thenextdayforhearings in theHouseandSenate.Heandhisstaffhadbeenbriefing lawmakerssinceMarch11,but thiswouldbethefirstopportunityformembersofCongresstoquestionthechairmaninpublic.Mediacoveragewasacertainty.

The day wasn’t over yet. At about 10:00 p.m., the NRC team watchedJapanese television footageofsmokepouring fromUnit3.TEPCOannouncedthatradiationlevelswererising.Ashorttimelater,U.S.mediabeganreportingthatTEPCOwaspullingitsworkersfromtheplant.Althoughitwasunclear ifthat meant everyone, this was extremely troubling news. Without sustainedintervention,theplantconditioncouldquicklydeteriorate.

JimTrappandTonyUlses,whohadcalledintoWhiteFlint,confirmedthatradiationlevelswerehigh.“Unit4isinshambles,”Trapptoldhiscolleagues.HehandedthephonetooneofAmbassadorJohnRoos’sassistants,whoaskediftheNRC headquarters knewmore about the status ofworkers at the plant.MartyVirgilioreadaloudaWashingtonPostbulletin:“TheskeletoncrewremainingatFukushimaDaiichiNuclearPowerPlantisbeingevacuatedbecauseoftheriskstheyfacefromdangerousradiationlevels.”(Thiswasn’tquiteaccurate; it laterturned out that the workers had been pulled from the heavily contaminatedcontrol roomsbut remainedon-site,available to return ifneeded.Nonessentialpersonnel had departed the plant, but they eventually returned.)The linewentdead briefly and then Ulses explained the interruption: “We just had anearthquakehere.”

Inside the Seismic Isolation Building, superintendent Yoshida and his fellowworkers often had to rely on reports from the emergency crewsmaking briefforays out onto the plant grounds to knowwhat was taking place. Only thenweretheyabletoassessjusthowbadthingshadgotten.Afteroneexplosion,themen inside could hear debris raining down on the roof of the bunker-like

building.“I really felt we might die,” Yoshida told a reporter in a rare interview,

nearlyayearandahalfaftertheaccident.1

Working conditions in the Seismic Isolation Building rapidly worsened.Personal dosimeters, used to measure radiation levels, were in short supply.Manyhadbeendestroyedbythetsunamiorrendereduselesswhentheirbatteriesdied.Thosestillfunctioningwerereservedforworkersforcedtoventureoutside.Protective clothing also became scarce.Meals consisted of biscuits and driedfood,andwaterwasrationed.Crewssleptinthehallways.

Tosupporthispeople,Yoshidasaid,hepassedoutcigarettesintheheavilyused smoking room. He encouraged them to record their names on a largewhiteboardasamemorialincasetheydidnotsurvive.Inthecircumstances,hetoldtheinterviewer,“itwasclearfromthebeginningthatwecouldn’trun.”

TapesfromthevideoconferencelinkbetweentheSeismicIsolationBuildingandTEPCOheadquarters, releasedbyTEPCOmore thanayear later, revealachaoticscene.TempersflareasYoshidaandhis teamarebesiegedwithordersand counterorders from TEPCO headquarters, which was also gettinginstructionsfromtheprimeminister’soffice.

Yoshida would later tell government investigators he believed TEPCO’schainofcommandduringtheaccidentwas“disastrous.”WhenhewasorderedonMarch12tosuspendinjectingseawater—theorderheignored—Yoshidasaidhethought:“Whatthehellistheofficetalkingabout?”

ByMarch18,hispatiencehadallbutrunout.Whenofficialsatheadquartersdirectedhimtosendcrewsouttoconductanothercheck,Yoshidasnapped:“Mypeople have beenworking day and night for eight straight days. . . . I cannotmakethembeexposedtoevenmoreradiation.”

In theweehoursofMarch16,EastCoast time,Charles“Chuck”CastocalledWhite Flint from Tokyo, where he had arrived a short time before. Casto, adeputy regional administrator in theNRC’sAtlantaoffice,hadbeenchosen toheadtheNRCteaminJapan.2(Hewouldspendalmostayearthere.)Alongwitheight other NRC staff members, Casto joined Trapp and Ulses in the U.S.Embassy.TheNRCcrewsetupshopinalargeconferenceroom.

CharlesCasto

BillBorchardt

MartyVirgilio.U.S.NuclearRegulatoryCommission

Thefirst thing thatDanDorman, inchargeovernightatWhiteFlint,askedCasto forwas an update on theUnit 4 spent fuel pool.Casto promised to getwhathecould.“Asyouknow,”hesaid,“thecommunicationschannelsareverylimited.”Eventhoughhehadarrivedsorecently,Castohadpickedupthehighlevelofconcernpervading theembassy.“[T]hey’reworriedabout the170,000[sic]Americansoverhere,”hesaid.“That’stheirprimarygoal.They’reheretoprotectthem....[T]hat’sgottobeourfocus.”

MartyVirgilio,whowas on the line inWhite Flint, concurred. “[T]he toppriority is to support the ambassador and theU.S. citizens there. I would saysecondissupportfortheJapanesegovernmentintherecoveryofthesereactors.And,then,thirdisgatheringinsightsandlessonslearnedforus,sothatwecanassesstheimplicationsforour[reactor]operatingfleetandapplicants.”

Late the previous evening, a RASCAL simulation had estimated radiationdosesfromaspentfuelfireinapoolthathadlostallitswater,aswellasitsroof,andreleased50percentofitsradioactivecontentstotheatmosphere.Justasforthe case of Unit 2 with no containment, the calculation indicated evacuationwouldbeneededatleastouttofiftymilesdownwind,RASCAL’slimit.Sonowtwopossiblescenarioswouldwarrantafifty-mileevacuation,andtheNRCstillhadnowaytoknowwhethereitherwasoccurring.

But a decision had to bemade soon on evacuation advice toAmbassadorRoos, and theNRC team needed to judgewhether its disaster scenarioswereplausible. There would be hell to pay if the United States expanded theevacuation zone and it turned out that theUnit 2 containment remained intact

andtherewasnospentfuelfireatUnit4.The lack of solid data about the status of Fukushima Daiichi frustrated

everyone.“Itwasliketryingtoinvestigateahomicideandnothavingaccesstothe crime scene,” Casto would later say. “There was just so muchmisinformation, lackof information, andyoudidn’tknowwhat information totrust.”TheNRCcrewatWhiteFlintagreedtotryhardertogetdetailsoutoftheU.S. and international nuclear industry. GEHitachi, for instance, had its ownemergency operations center in Tokyo; if need be, Casto suggested, Virgiliocouldasktop-levelGEofficialsintheUnitedStatesforaccess.

Casto had spent a portion of the fourteen-hour flight toTokyo buried in acouple of NRC technical publications (known as “NUREGs”) relevant to thecrisis.Fordecades,theNRChasfundedcontractorsatU.S.nationallabstoruncomputer simulations of possible reactor accidents. Casto was struck by howcloselythesesimulationsmatchedthereal-worldsituationatFukushima.Ashetoldhiscolleagues,“ofcourse, thatMarkIcontainment is theworstoneofallthecontainmentswehave . . . thisNUREGtellsyou that inastationblackoutyouaregoingtolosecontainment.There’snodoubtaboutit.”3

About ninety minutes later, John Monninger, an engineer with Casto’sgroup, calledWhite Flint to report that the NRC team had been invited to ameeting with TEPCO and Japanese nuclear regulators. TEPCO apparentlywantedguidanceondealingwith spent fuel pools.Monninger also sharedbadnews:thepools inUnits1and2were“boilingdown.”ThoseinUnits3and4weredisplayingzirconium-water reactions,meaning that thefuelwasexposed.Further, the explosion at the Unit 4 reactor building had “leveled the walls,leveled the structure for the Unit 4 spent fuel pool all the way down to theapproximate level of the bottomof the fuel,”Monninger said. “So, there’s nowaterintherewhatsoever.”

TEPCOwastalkingaboutdumpingsandinthepool,whichwouldreducetheradiationlevelsbutdonothingtocooltheoverheatedfuelrods.TheNRCgroupagreedthatacombinationofwaterandboron(toreducetheriskofcriticalityinthe pool) seemed the best answer. The headquarters teammembers promisedMonninger that they would come up with further suggestions before theircolleaguesinTokyoleftforthemeetinginaboutforty-fiveminutes.

WhiletheNRCwasprojectingradiationdoselevelsundervariousscenarios,theDOE’sOfficeofNavalReactorswasdoing its ownassessments, andbothagencieswerefeedingtheirrecommendationstotheU.S.ambassador.Thetwo

groupsweren’t seeingeye toeye, it seemed.To theOfficeofNavalReactors,theradiationreadingsdetectedonnavalvesselsandatbasesfarfromFukushimaindicatedthattheeventwasmuchworsethantheNRChadpaintedit.WhiletheNRCwasestimatingtheradiationreleasefromdamagedfuelinasinglereactor,expertsatNavalReactorssawafargreaterdanger;theybelievedtheNRCwas“undershooting”thepotentialrelease.AsStephenTrautman,deputydirectorofNaval Reactors, told theNRC by phone, “[I]f we end up losing one of theseplants,there’sagoodpossibilitywe’regoingtolosealloftheseplants.”Thetwosidesagreedthatthethreatsfromthespentfuelpoolsalsohadtobefactoredin.

ForU.S.officials, theevacuationdecisionwasadelicatebalancingact.OnMarch 13,AmbassadorRoos had put out a press release tellingAmericans inJapan to “follow the instructions of Japanese civil defense authorities,” whowere evacuating only a 12.4-mile (twenty-kilometer) zone around Fukushima.Now the ambassadorwas getting information that suggested the advicemightnot be sufficient. Yet if theUnited Stateswere to unilaterally launch awiderevacuation,itcouldangeranimportantally.

Within the embassy itself, fearswere high.WhenCastomade trips to thecafeteria,hewasoftenstoppedbystaffmembers,includingpregnantemployeesworried about their unborn children, asking: how bad is it? “There wassignificantconcern,”herecalled.

To arrive at a unified recommendation forAmbassadorRoos, a high-levelphone conference was arranged with Naval Reactors and the NRC teams inJapan andWhite Flint. During the call Jaczko asked: “[D]o we think this isgoing togetbetterorgetworse?”MartyVirgilio responded,“It’sgoing togetworseifyouthinkaboutthespentfuelpools.Rightnow,Unit4doesn’thaveaspentfuelpoolanymore.”Waterlevelscouldn’tbemaintainedintheUnits1,2,and3fuelpools,headded.

Atworst,Jaczkosummarized,theaccidentcouldinvolvethreereactors“outofcontrol”andpossiblyuptosixspentfuelpools.Theambassadorshouldbaseany evacuation decision on that information, he said, and then asked: “Doesanybodydisagreewiththat?”

“Chairman,”saidAdmiralKirklandDonaldofNavalReactors,“Iagreewithyou.”

“If this happened in theU.S.,” addedBillBorchardt, theNRC’s executivedirectorandaveteranoftheU.S.nuclearnavy,“wewouldgoouttofiftymiles.Thatwouldbeourevacuationrecommendation.”

Itwasabout6:30a.m.Wednesday,March16.ItwastimetocalltheWhiteHouse.

Jaczko’s summary to personnel in the White House Situation Room wassuccinct. In even terser language, a White House official repeated Jaczko’sreport toconfirm:“Threereactorsmeltingdown,sixspentfuelpondsgoupinflames.Andwhat,then,wouldbetheimpactforTokyo,forexample,ifthewindkeptblowinginthatdirection?”

“At thispoint, I thinkIwouldstillgowith the fiftymiles rightnow,”saidJaczko,notingthelackofsolidinformation.However,hecautionedthateveniftheestimateswereonly“offbya littlebit,” the impactcouldbe“significantlylarger.”

Before Jaczko’s scheduled 9:30 a.m. testimony on Capitol Hill, he andBorchardt, whowas accompanying the chairman, called in toWhite Flint forupdates.Whichposedthelargerthreatnow,Jaczkoaskedhisteam:Unit2orthespentfuelpools?Thepools,hewastold.

AfterJaczkohungup,Borchardtremainedonthelinetoseekmoredetails.Casto,participatingfromJapan,said that inadditionto the threatposedbytheUnit4spentfuelpool,onehadtoassumethatconditionsattheotherendangeredreactors and spent fuel pools would also deteriorate because the NRC teamwasn’tseeingany“mitigation”oftheongoingcrisis.

Borchardt asked: “I just want tomake sure that no one takes anything he[Jaczko]saysasimplyingthat,iftheyresolvetheissueswithUnit2,lifeisgoingtobealotbetter.Right?”

“No,”someoneelseonthecallreplied.Discussions atWhite Flint now focused on howbest to dealwith the fuel

pools.TheJapaneseweretalkingaboutusingahelicoptertoflyoverUnit4anddumpsandorwaterintothegapingholewheretheroofofthebuildinghadbeen.Castowasgrowingimpatient.“Idon’tknowwhatthey’rewaitingfor.”

Radiationlevelsatsixty-fivefeet(twentymeters)abovetheopenpoolwouldbe“hundredsofthousandsofrads,”camethereply.HelicopterpilotswhoflewoverChernobyltodumpsandontheburningreactorthere“flewuntiltheydied,basically,”saidonememberoftheNRCteam.

Borchardt called again to “triple-check” the fifty-mile evacuationrecommendation.Was it still a go? CharlieMiller said yes, based on currentmeteorological conditions. But if conditions changed, even a fifty-mile

evacuationmightnotbesufficient.Ifthewindshifted,Milleradded,evenTokyo—150milesaway—couldbeaffected.

A short time later, Monninger called White Flint to report that twogovernment ministry employees had asked for help acquiring emergencyequipment tomovewater from the ocean to the reactor buildings, plus watercannonsandfourorfivetruckswithaerialboomscapableofsprayingwaterataheightofsixty-fivetoonehundredfeet(twentytothirtymeters)toreachthefuelpools. All of this apparatus would need to be positioned quickly because theradiationlevelnearthereactorswasthirtyrem(threehundredmillisieverts)perhour. Robots with remote cameras and radiation measuring equipment alsowouldbeuseful,theJapanesesaid.

“Onething,wewentbackandforthon[the]Unit4[spentfuelpool],”saidMonninger, “. . . becausewe believe thewallswere blown out and thewaterlevelisatthebottomoftheactivefuel.Thattookthemback,youknow,quiteabit. . . .Theysaidtheydon’thaveanyindicationsofthat.Theybelieve,whichwould be true, there will be screaming radiation levels if those walls wereknocked out. They said the walls . . . could have been knocked out, but thespent-fuelpoolwallmaynotbetheoutermostwall.”

TheJapanesehadshownMonningera“bird’seyeschematic”oftheUnit4spentfuelfloor.“Theyhadadecentlevelofconfidencethat . . . thespent-fuelpoolwallshadn’tbeenblownoutandthesuccesspathwastofloodthatupandnottogowithsand,dirt,orwhatever.”

Borchardt called again fromCapitolHill looking for anynew information.Monninger’sreportfromtheJapanesewasrepeated:“Theydon’tthinkthespentfuel pool forUnit 4 is as degraded aswe thought.”Borchardt asked formoredetails.Coolinginthepoolstillmaybepossible,hewastold.MonningeraddedthathebelievedreactorfuelhadbeenejectedintheexplosionatUnit4andwasnowlyingaroundtheplantsite,whichwouldexplainhighradiationreadingsontheground.TheJapanesewerebulldozingdirtovertherubble,andtheradiationlevelsdroppedbyasmuchas70percent.

“Sothepotentialissolelytorefillthepool?”Borchardtasked.“That’s correct,” came the reply.Even so,Borchardtwas told, “there’s no

change to the recommendations that we’ve made.” The fifty-mile evacuationstood.AsbestastheWhiteFlintcrewcouldtell,Units1to3haddamagedcoresandthespentfuelpoolatUnit4wasalmostdry.

TheNRChad sound reasons for its suspicions. Therewas no clear proof, buttherewasplentyofcircumstantialevidence.TheUnit4poolcontainedthemost,andthehottest,spentfuelamongthereactorsatFukushima.Itwouldthereforebethefirsttoboilaftercoolingwaslost.TheUnit4reactorbuildinghadblownapart, as TV replays nearly constantly reminded them; themost likely reasonwouldbethedetonationofhydrogengas.SincetheUnit4reactorcoreheldnofuel,themostlikelysourceofhydrogengaswasexposedfuelinthepool.Ifthefuel were uncovered, its metal cladding could ignite—explaining the firereported inUnit4.And thehigh radiation levels reportedbetween theUnits3and4buildingscouldbecausedbydebris,perhapsevenportionsof fuel rods,ejectedfromadryUnit4poolduringtheexplosion.

Finally, observers reportedwhite vapor emanating from theUnit 3 reactorbuilding while nothing visible wafted from Unit 4. Based on this latestcircumstantialevidence,itwasreasonabletoconcludethattheUnit4spentfuelpoolhadboiledordrained itselfdrywhile theUnit3poolwasboiling towardthatoutcome.

But still, therewas no definitive proof. The Japanese could turn out to berightafterall,butitwouldbemanydaysbeforeanyonecouldgetcloseenoughtoUnit4tofindout.

•••

Jaczkohadbeenscheduled todiscuss theNRC’s2012budgetwith twoHouseEnergyandCommercesubcommittees,butFukushimawasoneveryone’smind.BeforeJaczkocouldtestify,hewassummonedtoameetingattheWhiteHouse.Jaczko told President Obama and his national security advisors that the NRCrecommended the evacuation of Americans living within fifty miles ofFukushimaDaiichi.Itwas,thechairmansaid,theadvicetheNRCwouldgiveifthisincidentweretakingplaceintheUnitedStates.

NRCchairmanGregoryJaczkotellsaHousesubcommitteehearingonMarch16thattheNRCbelievedthespent fuel pool atUnit 4was dry, raising the possibility that the spent fuel could catch fire and releaseadditionalradioactivematerial.TheannouncementcameshortlyaftertheUnitedStatesadviseditscitizensliving within fifty miles of Fukushima Daiichi to evacuate or remain indoors if evacuation were notpossible.U.S.NuclearRegulatoryCommission

Ashorttimelater,WhiteHousePressSecretaryJayCarneyalertedreportersto the expanded evacuation recommendation during a briefing. The StateDepartment had issued a travel warning half an hour before, citing the“deteriorating situation”atFukushimaDaiichi.U.S. citizens livingwithin fiftymiles (eighty kilometers) of Fukushima were advised to leave or take shelterindoorsifevacuationwasnotpossible.Inaddition,thewarningsaid,“theStateDepartmentstronglyurgesU.S.citizenstodefertraveltoJapanatthistimeandthoseinJapanshouldconsiderdeparting.”

Washington’sfifty-mileevacuationrecommendationwasabouttogetsomecompetition in the news. Before he began his testimony on Capitol Hill thatafternoon,JaczkocalledintotheWhiteFlintoperationscenter.“[J]usttorepeat,webelievepoolNo.4isdry,andwebelieveoneoftheotherpoolsispotentiallystructurally damaged?” he asked. “That’s correct,” Chuck Casto said fromTokyo.“That’sthebestweknow.”

“Imeantherelevantfactorisit’sdry,”saidJaczko.“Yes,”Castoconfirmed,“andtheycan’tmaintain[water]inventoryatall.”

Jaczkohungup,buttheconversationcontinuedbetweentheNRCexpertsinTokyo andWhite Flint. They realized they had neglected to tell the chairmanthattheJapanesedidn’tagreewiththeNRC’sassessmentabouttheUnit4pool.They didn’t call him back, though, because they thought he didn’t want that

levelofdetail.Andtherewereplentyofotherproblemstoworryabout.TheUnit2 spent fuelpoolnowappeared tobe in trouble; steamwas rising through theholecreatedinthatreactorbuilding’swallbytheUnit1explosion,sothatpoolmight be boiling dry. Steam or smoke was coming from the Unit 3 pool,meaning thewater level there couldbedropping.Unit 1 appeared to have theonlypoolofthefournotinimmediatetrouble.

WhenJaczkotookhisseatinthelargeHousehearingroom,helaunchedintothelatest news from Fukushima. At three reactors there is “some degree of coredamagefrominsufficientcooling,”hesaid.AtUnit2,coolingwasnotstablebuttheprimarycontainmentwasfunctioning.WaterlevelsintheUnit2spentfuelpoolweredecreasing.TheintegrityoftheUnit3poolhadbeencompromised.

Thenhemovedon toUnit 4. “Webelieve that secondary containmenthasbeendestroyedand there isnowater in the spent fuelpool,”he said,“andwebelieve radiation levels are extremely high, which could possibly impact theabilitytotakecorrectivemeasures.”JaczkosaidthehighestprioritynowwastomaintaincoolingofthereactorsatUnits1,2,and3andtokeepwaterlevelsupinthespentfuelpools.Ifcoolingfunctionsshouldfail,hewarned,“itwouldbeverydifficultforemergencyworkerstogetintothesiteandperformemergencyactions.”

What poses the highest risk at themoment, askedRep.HenryWaxman, aCalifornianwithalonginvolvementinnuclearsafetyissues.

“Allof thefactors together, really, thecombination,”Jaczkosaid.“There’sthe possibility of this progressing further.” If the cooling systems failed, heexplained, emergency workers “could experience potentially lethal doses in averyshortperiodoftime.”

Jaczko hustled out of the House hearing and across Capitol Hill to theSenate, where Bill Borchardt had been pinch-hitting for his boss before theSenate Environment and Public Works Committee, which had convenedspecifically for a briefing on Fukushima. The chairmanwas grilled about thesafetyofU.S.reactors,especially those inseismicallyactiveareas,suchas thetwo in the home state of the committee’s chair, California senator BarbaraBoxer.

After Jaczko’s testimony, the committee heard from representatives of theUnion of Concerned Scientists and the Nuclear Energy Institute (NEI), theprimary nuclear industry lobbying group inWashington. They were asked to

addresswhether aFukushima-type accident could happen in theUnitedStatesandifso,whatneededtobedonetoprecludesuchadisaster.

Tony Pietrangelo, chief nuclear officer of the institute, chose his wordscarefully:“IthinkIunderstandyourconcern,becauseIshareit,thatpeopleareseeingwhat’shappeninginJapanandthey’rescared.Wecanneversaythatthatcouldneverhappenhere.There’snosuchthingasaprobabilityofzero....Butwhat I would tell you is it doesn’t matter how you get there, whether it’s ahurricane,whether it’s a tsunami,whether it’s a seismic event, whether it’s aterrorist attack,whether it’s a cyberattack,whether it’s operator error or someotherfailureintheplant,itdoesn’tmatter.Wehavetobepreparedtodealwiththoseevents.”

Edwin Lyman of the Union of Concerned Scientists agreed that aFukushima-type event could not be ruled out in the United States: “We haveplantsthatarejustasold.Wehavehadastationblackout.WehavearegulatorysystemthatisnotclearlysuperiortothatoftheJapanese.Wehavehadextremeweather events that exceeded our expectations and defeated our emergencyplanningmeasure[s],[suchas]HurricaneKatrina.”

WhilePietrangelosaidthat theindustryhad tobepreparedtodealwithsevereevents like natural disasters, he did not say that the industry actually wasprepared todealwith them. In fact,he told thecommittee thatFukushimahadprompted an industry-wide effort to “verify each company’s capability tomitigateconditions thatresult fromsevereadverseevents,” includingtotal lossofelectricpower,earthquakes,andfloods.Atthetime,hedidnotanticipatethatthosereviewswouldturnupnumerousproblems,callingintoquestionthelevelofpreparednessofU.S.reactors.

Pietrangelo informed Boxer that “we already have mobile—diesel-drivenmobilepumpsoneverysiteinthecountrythatcanbemovedaroundthesitetoprovide another contingency measure should we lose a cooling source. Andthere’scountlessothermeasureslikethat.”

Those measures are known as “B.5.b,” named after the section of theregulatoryorderswheretheyappear.4TheywereamongthestepsthattheNRCrequiredutilitiestotakeafterthe9/11attackstopreparefor“lossoflargeareasofaplantduetoexplosionsorfire”—thekindofdamagethatmightbeexpectedfromaterroristaircraftattack.Forexample,utilitiesmuststoreB.5.bequipmentfarenoughawaythatitmightbeabletosurviveaplaneattackonareactor.But

thereisnorequirementthattheequipmentsurviveothertypesofdisasters,suchasanearthquake.WhenLymanaskedabouttheabilityoftheemergencypumpsto survive an earthquake, Pietrangelo said that the pumps are not certified towithstandanyearthquakeatall,muchlessasevereone.

Inotherwords, in thefaceofaFukushima-scaleevent, theB.5.bmeasurescouldwellbeworthless.ButinthedaysafterFukushima,boththeindustryandthe NRC cited the B.5.b measures in response to the question they had bothfeared:“Canithappenhere?”

Jaczko’sassertion that theUnit4spent fuelpoolwasdryapparentlydidn’t sitwellwith the Japanese.Casto andTonyUlseswere invited to theKantei, theprimeminister’sofficialresidenceandoffice.TheJapanesewantedtoshowtheAmericansavideooftheUnit4spentfuelpool—indicatingitcontainedwater.MonningertoldtheWhiteFlintcrew:“Wethinkthereasonthey’redoingthatisbecause, I guess, of maybe statements the NRC has made or maybe thechairman’s hearing testimony . . . saying that Unit 4 the spent fuel pool wasdry.”

Ashort timelater,Castoreportedbackafterwatchingthevideo,whichtheJapanesedeclinedtoprovidetotheAmericans.“Youknow,it’snotveryclear.You’retalkingaboutahelicopterthat’stryingtodoalotofthingsatonceinafield.Andtheytriedtoscanallfour[reactor]units.Youhavetolookthroughawindow.And they claim there’s a reflectionofwateron theUnit 4 spent-fuelpool. . . .There’ssomethingthere.Youdon’tknowif it’ssteelorwater.Theyclaimit’sareflection.”

Steamwasvisiblecomingfromthesideofthebuildingnearestthespentfuelpool, said Casto, obviously frustrated. “You’ve got a building that’s had anexplosion and has debris everywhere, and you’re trying to look at it with ahelicopterthat’sflyingbyinsplitseconds.Youcan’ttellanythinginthere.Youknow,theyclaimthere’saglimmerofareflectionbut,youknow,it’ssteaming.Unit3issteamingevenharder.”

Jaczko,whohadjoinedthecall,interruptedCasto.“So,atthispoint,younolonger believe that the pool is dry?” Casto replied: “I would say, as of fiveo’clockyesterday,thepoolhadsomewaterinit.”

“Okay.NowI’vesaidpubliclythepoolisdry,”saidJaczko.“Doyouthinkthat’sinaccurate?”Castoreplied:“Iwouldsayit’sprobablyinaccuratetosayit’sdry.”

“DoyouthinkIneedtorollbackanyofthestatementsthatImade?”Jaczkoasked.

“I don’t think so,” Casto said. “Itmay not have been dry, but it certainlywasn’tfull.”Therewasnoneedtochangethefifty-mileevacuationadvisory,theteamassuredJaczko.

AsdebateswirledatWhiteFlint,PresidentObamaandPrimeMinisterKanwereonthephone.ObamapromisedcontinuedtechnicalassistancetoJapanandthe two leaders discussed the steps theUnited Stateswas taking to protect itscitizens. After the conversation, Japanese cabinet secretary Yukio Edano toldreporters in Tokyo that the two countries would do a better job of sharinginformation.

AsfortheAmericans,everyoneunderstoodthattheUnitedStatesneededtotreadlightly.AsChuckCastolaterobservedofthesituation:“Thebestsciencepersoncan’tbringsciencetoitiftheydon’thavetherightdiplomacyskills.”

ConvincedthattheUnit4spentfuelpoolheldwater,theJapanesefocusedtheirattention on Unit 3. The white smoke seen billowing from that unit the daybefore—aswellasaspike inradiation—madegettingwater to thefuel thereapriority.A three-pronged attack began shortly before 10:00 a.m. onThursday,March17.

It consisted of dropping water from Self-Defense Forces helicopters andsprayingwater fromthegroundusingSDFfire trucksandhigh-pressurewatercannon trucks that the Tokyo Metropolitan Police Department used for riotcontrol.5

AninitialattempttodumpwaterfromanSDFhelicopteronMarch16hadbeenabandonedbecauseofhighradiationlevels.Leadplateslinedthebelliesofthe helicopters and the crewswore protective clothingwhen they took off thenextday.

Over the course of ten minutes, two CH-47 Chinook helicopters droppedthirtytonsofwaterontheupperpartsoftheUnit3reactorbuildingduringfourflights.NHKtelevisioncameras,positionedabout twentymilesfromtheplant,captured the drops in footage viewed around the world. Although a smallamount of white steam rose from the building, very little water apparentlyreachedthepool.Mostwascarriedoffbystrongwinds,andsomewasdeflectedby debris atop the pool. The water cannons were useless and the fire trucksproved inadequate; neither could deliver the water where it was needed.

Radiationlevelsprohibitedmovingtheequipmentcloser.TEPCOalsofocusedonrestoringpowertotheplantviaanewtransmission

line,althoughutilityofficialswereunabletosaywhenthatmightbecompleted.Theplancalled for repoweringUnit2 to restorecooling to its spent fuelpool.BecauseUnit2’sreactorbuildingwasintactasidefromasmallhole,itwouldbedifficulttospraywaterinside(incontrasttoUnits1,3,and4,whichnolongerhadroofs).Butgiventheextensivedamagetotheplant’swiringsystems,therewasnoassurancethatoff-sitepowerwouldbeofmuchuse.

Thefirst radiationreadingsgatheredby theU.S.NationalNuclearSecurityAdministration’s Aerial Measuring System, part of the DOE’s RadiologicalAssistance Program,were providing independent data.Until now,most of themeasurements had come from TEPCO via NISA, andWashington wanted itsown.TheU.S.sensorsnotonlymeasuredhowmuchradiationwaspresent,butalso identified the isotopes emitting it—the nuclear fingerprints of dangerousmaterials including cesium-137. In addition, a U.S. Air Force Global Hawkdrone flew over the plant site, measuring temperatures and gathering high-resolutionimagery.

WhiletheJapanesestruggledtogetwaterintothepools,theAmericanswereofferingfiveheavy-dutypumpsfromtheU.S.DefenseThreatReductionAgencythat were available for pickup three hours away from the plant. (Earlier, theJapanesehadrejectedtwofiretrucksofferedbytheU.S.AirForcebecausethevehicleswerenotregisteredinJapanandthuscouldnotbelegallydrivenontheroadways, an act of bureaucratic nitpicking that amazed the Americans.) Thepumpscoulddeliver seawater to the fuelpools—assuming thepoolswere stillintact. ThatworriedCasto. “The pumping strategymay not be useful at all ifthereisnospentfuelpool,andthereisjustarubblebedintheresomewhere,”hesaid.

Evenso, it seemeda logicalplanofattack.At6:00a.m.onMarch17, theJapanese SDF picked up the pumps at Yokota Air Base and set out forFukushimaDaiichi,196milesaway.

•••

Deliveringthewaterwouldrequiremorethanpumps,however,andU.S.expertshadspenthoursconferringonjustwhatwasneeded.Pipesandstrainers(tokeepdebrisintheoceanwaterfromcloggingthepumpsorthespraynozzles)hadto

beacquired.Becauseoftheextremelyhighradiation,installationofthesystemhad tobecompletedas rapidlyaspossible. “[I]t’sgot tobeon tractor-trailers,minimumdisconnect,”onememberoftheU.S.teamsaid.“Theywoulddrivein,hookthis thingup, throwtheportablesubmersiblepumpout in theocean,andlight this system off and leave.” The NRC asked the giant engineering firmBechtel Corporation to design the complete cooling systems that would beneeded and to arrange for procurement and delivery of all the additionalequipment to the site, but not to perform the dangerous jobs of installing andoperatingthesystems,whichwouldbelefttotheJapanese.

The NRC was developing a radiation dose map of the plant site to helpinstallers minimize their exposure. “[I]t’s going to be heroic efforts, becauseyou’regoingtohavesomebodyrunningtowardthepool,”saidoneoftheWhiteFlintstaffers.Boronwouldbeaddedtothewatertoreducethelikelihoodofthespentfuelgoingcritical.TwentythousandpoundsofboronhadbeenlocatedatCalifornia’sDiabloCanyonnuclearplantandwasbeingflownfromVandenbergAirForceBasetoYokota.

An exhaustedChuckCasto called in toWhite Flint to say the pumps hadarrivedattheplantandeffortswerenowunderwaytoreducetheradiationlevelswithsandorleadshieldingsothesystemcouldbeinstalled.“[Y]ouknowtherearelethaldoseratesthey’regettingoutsidethatbuilding,”saidCasto.

Thediscussion turned toUnit2, andCastowasaskedabout its status:hadthe primary containment been breached?He did not know.ANISA summarywasvague,Casto said, referringonly to thepossibilityof an “incident” in thesuppression chamber, based on the sound of an explosion and a subsequentreductioninthemeasuredpressureinthetorus.

For a moment, the magnitude of the crisis for the Japanese overwhelmedCasto,whonoted thata thousandbodieshadwashedashore fromthe tsunami.“[I]t’shelloverhereforthatgovernment.Imean,it’sjustabsolutelyhell.AndIknowwegetfrustratedwiththem,but,man,whenyouthinkaboutwhatthey’refacedwith,it’sabsolutelyunfathomable.”

AlthoughtheUnitedStateswasworkingoutdetailsonthepumpsystem,itwasaone-sidedeffort.“Wearenotgettingany takers fromtheJapanesesideof thisequation,” Virgilio told his colleagues. Although the SDF had collected thepumpsanddeliveredthemtotheplant,theJapaneseapparentlywereafraidthattrying to hook up the system would be too dangerous because of the highradiation levels. So they were intent on continuing their spraying operations.

“Theyareusinghelicoptersthesamewayyoufightforestfires,”saidamemberoftheAmericanteam.

Atabout8:00a.m.Thursday,DanDorman,ondutyatWhiteFlint,briefedtheNRCteamviaaconferencecall.EventshadmovedbothUnit4andUnit2down the list of concerns.The highest priority nowwas theUnit 3 spent fuelpool, which appeared to have experienced a zirconium-water reaction and aresultingfire,hesaid.Overtheprevioustwelvehours,theJapanesehadtriedtodrop and spraywater into theUnit 3 pool, butwithoutmuch effect. SeawaterinjectiontothereactorvesselscontinuedinUnits1,2,and3,withwaterlevelsinthecoresatabouthalftheheightofthefuel.Thereweremixedreportsonthestatus of the Units 2 and 3 containments. TEPCO was still trying to restorepowertothesite.Thepumpswereinplacebutitwasnotcertainthattheycoulddevelop enough pressure to spraywater high enough to reach the pools.Newradiationmeasurementshadbeencollectedbyaircraftovernightandwerebeinganalyzed. Radiation levels of 375 rem per hourweremeasured three hundredfeetabovetheUnit3reactor.

Toeveryone’ssurprise, theJapaneseasked theNRCto list itsprioritiesoncontrolling the situation at Fukushima Daiichi. Although the turnabout waswelcome, fulfilling the requestwould put theNRC in the position of directlyofferingadvice,somethingithadthusfaravoided.MakingamistakeweighedonCasto. “I don’twant to try any strategy that doesn’t have soundmeasures, orreasonablysoundmeasures,ofsuccess,”hetoldVirgilio.“BecausethelastthingwewanttodoismakethesituationworsefortheJapanese.We’regoingtoownthisthingifwedo.”

Radiation exposure fears were growing beyond the vicinity of FukushimaDaiichi. The NRC was aware that significant levels of fallout could occuroutsideof thefifty-mileevacuationzone.Fordataonthat, ithadtodependontheDOE,whichwasusingitsmoresophisticatedatmosphericmodelingtoolstodevelopdoseprojectionsextendingonehundredandfiftytotwohundredmilesfrom the plant, an area that included Tokyo. The DOE was also runningsimulations toestimatepossibledoses to thepublic inAlaska,Hawaii,and theWestCoast,anditwasgettingsomealarmingresults:forinstance,dosesashighasthirty-fiveremtothethyroidsofpeopleinAlaska.TheNRCdidn’ttrustthenumberstheDOEwascomingupwith,butitdidn’thavethemeanstodisprovethem.

In theUnited States, theDepartment ofHomeland Securitywas screeningpassengersreturningfromJapan.InChina,grocerystoresinseveralcitieswere

strippedofiodizedsaltafterrumorsspreadthataradioactivecloudwasmovingin. Some buyers mistakenly believed that iodized salt would protect againstradiation; others feared that sea salt supplies from the coast would becontaminated. The city of Florence, Italy, sent a plane to Japan to pick up itsstranded orchestra and the conductor, Zubin Mehta. (Maestro Mehta wouldreturnamonthlaterforaperformancetobenefitdisastersurvivors.)

Casto and the NRC squad in Tokyo were swamped with meetings—with theambassadorandembassystaff,withotherU.S.officialsaidingintheAmericanresponse, with Japanese government officials. The crew was running on sixhoursofsleeporless,withsessionsstretchingwellintotheearlymorninghours.Noticeablyabsent,however,wererepresentativesofTEPCO.Theutilityseemedintentongoingitalone.

Finally,TEPCOofficialsdidagreetositdownwiththeAmericanstodiscussa pumping system the United States had proposed for cooling the spent fuelpools.ItwasthefirsttimetheutilityhadheardoftheU.S.plan,Monningertoldhis colleagues at White Flint. Apparently NISA and METI, which had beeninvolvedinthediscussionsoftheU.S.plan,hadnotbotheredtoappriseTEPCO.

Yet theUnited States had already givenBechtel the go-ahead to assemblefour separatepumping systems,or “trains,”one for eachof the fuelpools.ByMarch18,thecomponentshadbeengatheredinAustralia,awaitinganairlifttoJapan.OnlythendidtheU.S.teamdiscoverthattheTokyoFireDepartmenthadassembled a similar pumping system with local parts for use at FukushimaDaiichi.

Nomatterwhosesystemwouldbeused,theproblem,ofcourse,wasthefinalleg:gettingcloseenoughtolaywaterlinesnearthereactorsandpools.RadiationlevelsbetweenUnits2and3nowrangedbetween450and600remperhour.

TEPCO’s preferred and potentially less risky approach was to use twoconcretepumpingtrucks,similar tothoseusedtoencasetheChernobylreactorafterthataccident.Thetrucks,equippedwithboomscapableofextendingabouttwo hundred feet, could remotely spray seawater into the fuel pools withprecision.TwosuchtruckswereinJapan,andadditionalonescouldbeobtainedfromabroad.

Castowasstillworryingaboutpumpingwaterontothehotfuel.Theriskwasamassiveradioactivesteamcloud“that’sgoingto...paniceverybody.”

“We’re in such never-never land, and I don’t really know how to make

decisions when you have very little information,” Casto said, and urged hiscolleagues to seek additional guidance from experts inside and outside thegovernment. “We’re going to need all the great minds together,” he added.“Let’ssolve thisasanAmericannuclear industryhelping theJapanesenuclearindustry,notjusttheNRC.”

HELPFULHINTS

AstheexpertsinJapanandtheUnitedStatesstruggledtofindwaystocoolthecoresandstemtheradiationreleasesspillingfromFukushimaDaiichi,averageAmericanshadnoshortageofideas—noranyreluctancetosharethem.TheyfloodedtheNRCwithsuggestionsviae-mailsandphonecalls.

“I’msurey’allhavemanyexpertstryingtoassistintheemergencyinJapan,”wroteSharonH.,“butIthoughtIwouldwritejustincasethisideahadnotbeenconsidered”:cornstarch.

“Haveyouconsidered...finegroundblackpeppertosealthecrackatFukushimaDaiichi?”wroteShawnM.“Yes,commonhouseholdpepperisvery effective as a crack sealant. I once sealed a long crack (8") in anengineblock.ItheldforyearsandIdidnotneedtoreplacetheengine.”

Among other suggestions: Ping-Pong balls, antifreeze, a ski resortsnowmaker to blow snow into the core. Coal ash. An asbestos blanket.Liquidnitrogen.Putty.

Vinny S. proposed using tiles from the space shuttle. “The shuttleprogram is ending and we could recycle materials and be eco-friendlywhileensuringsafetyatthereactors.”

Othersweremoreinsistent:“GetthisinformationtoJapanortellthemwhen they call you,” directed one e-mail. “I was divinely led. God istellingmeitwillwork.”Whatfollowedwasadetailedlistofinstructionsentailing “vector forces,” a “metrogravitron particulator,” and a deviceknownasthe“Deometrian.”

MostsuggestionsreceivedastandardresponsefromtheNRC’sOfficeofPublicAffairs:“Weappreciatesuggestions thatworktowardresolvingthe situation in Japan; it’s reassuring to see how helpful and dedicated

private citizenshavebeen in lightof thisdisaster. . . .PleaseunderstandthattheNRChassomeofthemostexpertpeopleintheworldavailabletoassist the Japanese authorities in whatever way they request.” TheNRCsuggested the Americans also contact the Japan Atomic EnergyCommission.

One public-spirited citizen apparently got a runaround before finallylandingattheOfficeofPublicAffairs.HisnamewasHaroldDenton.He’s“been calling all overNRC,”wrote stafferAmyBonaccorso. In case thenamedidn’tringabell,sheaddedthatDentonwasthe“spokespersonfortheNRCduringThreeMileIsland—healsowastheperson[who]provideddaily reports to Pres. Jimmy Carter.” Denton, who also delivered dailybriefings to hundreds of reporters during theThreeMile Island accident,wantedtourgethecommissiontomakeitsexpertsavailabletothemedia,she wrote, because reporters “are reaching out everywhere for info . . .including retired employees (with old information).” Bonaccorso’s bosspromisedtocallDenton.

Stepping into the information void onMarch 15was TV personalityGlennBeck.“GlennBeckisnowexplainingtheChinaSyndrome,usingawokasacontainmentvessel,”anOfficeofPublicAffairsstaffere-mailedhis colleagues, to which one responded: “ohmigod.” “Maybe it’s a bigmixingbowl,Ican’ttell,”saidafollow-upe-mail.Thatwasn’tBeck’sonlyprop:M&Msmadehandyfuelpellets.

Thatcollaborationwasalreadyintheworks.Thenextday,Saturday,March19,agroupofexpertsfromindustrymetwiththeirgovernmentcounterpartsatWhiteFlint.Themodel,Virgilio explained,was thepublic-private response totheDeepwaterHorizonoilspillintheGulfofMexicoin2010.Attendingwererepresentatives from the Institute for Nuclear Power Operations, which wasorganizingthemeeting,GE,Exelon,theFrenchnuclearconglomerateAreva,theDOE, and the Electric Power Research Institute. Experts within the nuclearindustryhadregularlybeenconferringwiththeNRCandJapaneseauthoritiesaswell as conducting their own research.TheAmericans hoped that bymergingtheprivateandpublicresponse,TEPCOmightbecomemorereceptivetooutsidehelp.

The Japanesegovernmentmightalsoneed someconvincing. “We’regoingtostartworkingthroughdiplomaticchannelsin-countrytotrytomakesurethat

whatwe develop is implementable from a political standpoint,” saidVirgilio.Key to any public or private responsewas reliable data.And thatwas still inshortsupply.

5

INTERLUDE—SEARCHINGFORANSWERS:“PEOPLE...AREREACHINGTHELIMITOF

ANXIETYANDANGER”

From the first days of the accident,YukioEdano, a forty-six-year-old lawyer,became the faceof thegovernment.Aschiefcabinet secretary, responsible forcoordinatingtheexecutiveministriesandagencies,hewasomnipresentonliveTV.1

Although Edano gained certain celebrity status, his carefully wordedstatements later came in for criticism. Even as he announced evacuations, hefailed to adequately explain to the public the reason for the orders; otherimportantdetailsoftenweremissingfromhissummaries.

As the accidentunfolded, thebriefingsofvariousgovernment agencies, aswellastheupdatesprovidedbyTEPCOandNISA,othergovernmentministries,and localgovernments,wereadisjointedmixof reassurancesand frustratinglyvaguedescriptionsofwhatwastakingplaceattheplant.Attimes,theauthoritiesprovidedconflictinginformation.

ByMarch18,officialresponsestotheaccidentseemedtobecomeanumbersgame,withstatisticsbandiedaboutinaconfusingblur.Thatday,NISAelevatedtherankingoftheFukushimaDaiichiaccidentfromalevel4toalevel5ontheseven-levelInternationalNuclearandRadiologicalEventScale(INES)becauseoffueldamagetothecoresatUnits1,2,and3.Inapressreleaseannouncingthechange,TEPCOblamedthereactorcrisison“themarvelsofnature,”areferencetothetsunamiandearthquake.

While thesignificanceof that increase from level4 to level5undoubtedlyescapedmany in thepublic, for regulatorsand theJapanesenuclear industry it

wasasmuchasymbolicasasubstantivechange.Japan’sworstnuclearaccidentto date, the 1999 criticality incident at the Tokai fuel fabrication facility thatkilledtwoworkers,hadratedalevel4onINES.ThreeMileIslandwasalevel5,and now Fukushima Daiichi was joining Three Mile Island on that dubiousgloballist.

What Tokyo and the Japanese nuclear industry dreaded even more washavingtoacknowledgethattheaccidentwarrantedalevel7rating,definedasamajor accident with widespread health and environmental effects and theexternal release of a significant fraction of reactor core inventory. Only oneaccidentinhistoryhadbeendeemedthatserious:Chernobyl.

ItwouldbealmostfourmoreweeksbeforeJapaneseauthoritiesannounced—belatedly, according tomany—that the events in Fukushima indeed rated alevel 7 ranking. In the annals of nuclear history, Fukushima Daiichi andChernobylwouldforeverbelinked.

Edano’s news briefings routinely contained twomessages: the latest radiationreadingsposedno“immediaterisktohealth,”followedbythesewords:“Remaincalm.”TheJapaneseheardthatadvicefromtheirgovernmentfrequentlyduringMarch as radioactive plumes spilled from the plant, as the expanding dangerzoneforcedevacueestomoverepeatedly,andasauthoritiescontinuallyfailedtocontain—or even explain—the accident. If more evidence was needed thatthingswereoutofcontrol,videosof theexplosionsanddamageatFukushimaDaiichi played repeatedly on TV and websites, occasionally serving asbackgroundillustrationsfornewsreadersrepeatingthegovernment’sreassuringstatements.

Japan’s chief cabinet secretary Yukio Edano was the government’s primary spokesperson during theaccident.Frequentlyadvisingthepublictoremaincalm,helatercameundercriticismbyinvestigatorsfordownplayingtheseriousnessofthreatsposedbyeventsatFukushimaDaiichi.AP

Such assurances had begun to ring hollow. “People in Fukushima arereachingthelimitofanxietyandanger,”thegovernorofFukushimaPrefecturecomplainedaweekintotheaccident.Theyweren’ttheonlyones.AcrossJapan,millionsof people struggled tomake senseofwhatwashappening, andmanybeganlookingforalternativesourcesofinformation.

CriticismwasalsomountinginternationallyaboutJapan’scandorregardingconditionsattheplantandthedegreeofriskpostedbyradiationemissions.Thisclearlyhadgrownbeyondadomesticevent.Earlyon,fearsthatdangerouslevelsofradiationcouldcontaminateareasfarbeyondJapangainedlegitimacyinpartbecauseofthedearthofinformation.Thefragmentsofdataexpertscouldgleanfrom FukushimaDaiichi painted a picture often at odds with the assessmentscomingoutofTokyo.TheNRC’sexpertsundoubtedlywerenot theonlyonesabroadengagedindebatesaboutthepotentialradiationhazard.

The International Atomic EnergyAgencywas faulted for its sluggish andconfusing response. The agency’s head, Yukiya Amano, a career Japanesediplomat,paidaone-dayvisittoTokyoonMarch18toannouncethattheIAEAand the internationalcommunitywere“standingbyJapan.”Criticsargued thatinsteadof standing by, the IAEA should bewading in andparticipatingmuchmoredirectlyineffortstoassessthethreatsposedbythereactors.Someblamed

theorganization’sbackseatroleinpartonAmano’stiestoTokyo’spoliticalandnuclearestablishment.(ThatcriticismincreasedwhentheIAEAdeclaredinlateMaythatJapan’sresponsetotheaccidenthadbeen“exemplary.”)

However,evenif theIAEAcouldhavedonemore,itwashamstrungbyitslackofauthority to intervene in the internalnuclearsafetyaffairsofsovereignstates.Withregardtociviliannuclearpowersafety,theorganizationfunctionedmoretosetstandardsandpracticesthantobeanuclearcoponthebeat.Andatthe beginning, the IAEA scientists were as starved for information as thoseeverywhereelseoutsidetheJapanesegovernmentandTEPCO.

Logically,many Japanese turned to the newsmedia for help. There, too, theywere often ill served. For journalists, the events at Fukushima Daiichi posedunique reporting challenges. The accident superimposed a complextechnological failure involving multiple reactors on a catastrophic naturaldisaster that itself was a major story. Nuclear jargon was confusing andunfamiliar; radiation measurements were baffling. Information camesecondhand;accesstotheplantandthoseworkinginsidewasimpossible.

ReportersfromJapan’smajormediaoutletsstayedwelloutsidethetwelve-mile (twenty-kilometer) evacuation zone, not traveling closer formore than amonthaftertheaccident.Ratherthandoon-scenereporting,journalistsoftenjustrepeatedgovernmentandutilitystatements,supplementingthemwithinterviewsofacademicsorindustryspokesmen,whoseobjectivitysooncameintoquestion.

SomeforeignjournalistsandJapanesefreelancereportersventuredasclosetothedisastersceneastheycouldgo,talkingwithevacueesandprovidingvividdescriptions of the confusion and miscues in the accident response. At timestheiraccountsweresoatoddswithwhatmajorJapanesemediawerereportingthatthesejournalistswereaccusedofsensationalizing.

Theinternationalandindependentreportswereoftenpostedorstreamedonwebsites. For those with Internet access who saw the accounts, the events atFukushimaDaiichiseemedfarmorealarmingthanhowtheywereportrayedinregularupdatesfromofficialsources.

Advocacy groups, including the Citizens’ Nuclear Information Center,quicklybecamesought-afterprovidersoftrustedinformation.OnMarch12,thecenter began conducting extensive daily briefings in Japanese and in English,delivered by independent nuclear experts. Streamed live on the Internet, thesessionsprovideddetailsandanalysisoftenunavailableelsewhere.Theyquickly

developedalargefollowing,withviewerse-mailingquestionsfortheexpertstoanswer. International organizations, including the Union of ConcernedScientists, also conducted detailed briefings, posting transcripts and relevantdocuments online and responding to hundreds of media inquiries from theUnitedStates,Japan,andelsewhere.

As the days progressed, and the hunger for information grew, newmediaoutlets—the Internet, Twitter, blogs, Web-based broadcast media—played anincreasingly vital role. Some of the content for these outlets came from thosemost immediately affected: disaster victims, evacuees, and even emergencyworkerswhocapturedeventsoncellphonesorreportedthemviatextmessages,blogs,andTwitterfeeds.Again,thestoriestheytoldwereoftenatoddswiththeofficialassessments.

One of the most compelling accounts came from Katsunobu Sakurai, themayorofMinamisoma,adevastatedcoastalcommunityaboutfifteenmilesfromFukushimaDaiichi.Sakuraisatdowninfrontofacamcorder inhisofficeandpleadedforassistancefromanyone.Thenaturaldisasterandthenuclearaccidenthadmadeconditionsinhiscityuntenable,hesaid.Foodandfueldeliverieshadstopped;residentswhohadnotalreadyfledhadbeenorderedtoremainindoors.“WiththescarceinformationwecangatherfromthegovernmentorTEPCO,weareleftisolated,”Sakuraisaid,lookingintothecamera.“Ibegyoutohelpus.... Helping each other is what makes us human being[s].” The eleven-minuterecording,postedonYouTube,wasviewedbymorethantwohundredthousandpeopleinthecourseofthreeweeks,andreliefpouredintothebeleagueredcity.

Evenasup-to-datetechnologymadedisseminatingthenewsfasterandsimpler,many Japanese journalists labored under the influence of traditional politics,economics,andculture,whichdidnotrewardconfrontation.

Asaresult,TEPCOoftengotafreeridefrompotentialcriticsinandoutofgovernment, and it grew to symbolizemuch of what was wrong in corporatemanagementand regulatoryoversight in Japan.Despite itswell-knownhistoryof covering up safety problems, the utility was regarded by many as a“cornerstoneof corporate Japan,” relyingonpoliticalmuscle, publicgoodwill,anddeferentialwatchdogstokeepitsnuclearfacilitiesandthebillionsinvestedinthemoperatingwithoutseriouschallenge.TEPCOhadcommittedtobuildingmorereactorsathomeandoverseas,andwasevenplanningtohelpfundatwo-reactorprojectinTexas.Whatconfidencecouldreportershavethatthecompanywasnowbeingforthright?

In theabsenceofcompanypresidentMasatakaShimizu,whohadvanishedfrom public view, the utility put junior executives before the cameras toapologizefor“causinginconvenience.”Buttheyofferedlittleinthewayofnewdetails. TEPCO’s press releases occasionally omitted crucial information. TheutilityannouncedthatithadsuccessfullybeguninjectingseawaterintotheUnit2 reactor at 11:00 p.m. onMarch 14, for example, but failed tomention thatradiationlevelshadjumpedattheplantentranceaboutfourhoursearlier.

Members of the media camped out for days at TEPCO headquarters,squeezed intoa cluttered roomoff the first floor lobby.Utilityofficialswouldappeartomakebriefannouncementsatallhours.Whenpressedbyreportersfordetailsandexplanations,theyoftenwereunableorunwillingtoanswer.

Inbettertimes,TEPCOhadbeenasavvycorporatecommunicatorwithdeeppockets and enviable national clout. For years the company had financed asophisticatedandexpensivepublicrelationsprogramtopromotethebenefits—and safety—of nuclear power. TEPCO, like Japan’s other nuclear utilities,erectedelaboratevisitorcentersthatresembledthemeparks,filledwithanimatedcharacters extolling the wonders of nuclear power. TEPCO’s mascot, Denko-chan,promotedthecompanytotheyoungersetandtheirfamilies.

TEPCO ranked alongside Japan’s internationally known corporations—Panasonic,Toyota,Sharp—indollarsinvestedforadvertising.Butwhenthingswentawry,TEPCOseemedtohavenocrisiscommunicationsplaninplace,justasitlackedaworkableaccidentplan.

As for government officials, they also had incentives to downplay theaccident.Japanhadpinneditsenergyfutureonnuclearpower.Everyjournalistwasawareofthehistoricallyclosetiesbetweenindustryandgovernment.Whatconfidencecouldreportershavethatpublicofficialswouldnowprovidecrucialinformation that reflected poorly on such an influential industry—or on thepolicydecisionsthathadpromoteditsexpansion?

Publictrustwasanearlycasualty.Yettrustiscritical,notedaDiet-appointedcommittee,ledbyYotaroHatamura,thatinvestigatedthecrisisanddetaileditsfindingsinalengthyreport.TheInvestigationCommitteeontheAccidentattheFukushimaNuclear Power Stations of Tokyo Electric PowerCompanywrote,“Inappropriateprovisionofinformationcanleadtounnecessaryfearamongthenation.”

The report echoed the findings of another independent investigativecommission,whichcriticizedthegovernmentforwithholdinginformationonthebasis that ithadyet tobecompletelyverified.By“sacrificing ‘promptness’ in

ordertoensure‘accuracy,’thereisconverselyadangerofinvitingcitizen’s[sic]mistrust and concern,” the committee noted, acknowledging the difficultbalancing act that often faces officials in times of emergency. That wasparticularlytruewhennewswasfloodinginfrommultiplesourcesotherthanthegovernment.

Perhaps the greatest chasm betweenwhatwas being said andwhat the publicneeded to hear concerned the complex issue of radiation exposure and healthrisks.The looming question on everyone’smindwas the obvious one: arewesafe? There could be no unqualified answer; a “safe” level of radiation is anissue on which scientists and health experts often disagree. Even so, thegovernment failed to provide basic guidance, a criticism leveled by theHatamuracommittee.

Chief Cabinet Secretary Edano and others repeatedly used the ambiguousphrase “it does not have immediate effects on health.” As the Hatamurainvestigationnoted,thatexpressioncouldbeinterpretedintwoconflictingways:that the radiationwas harmless, or that itmight produce cancer, just not rightaway.Citizenswerelefttoferretoutthetruthontheirown.

Time and again, the government bungled its handling of the radiation andhealth issue. OnMarch 16, for example, as the United States was ordering afifty-mile evacuation for its own citizens in view of rising radiation levels,Edano declared that only the government’sNuclear SafetyCommission couldprovide an accurate analysis of radiation data. But the chairman of the NSC,HarukiMadarame,was occupied advising PrimeMinisterKan and apparentlyunavailable.OnMarch23,nearlytwoweeksintotheaccident,Madarameheldhis first news briefing and informed reporters that no analyseswere available“becauseweareveryunderstaffed.”

By then, citizen activists, armed with their own radiation monitoringequipment, had begun to gather readings around the country and post themonline. The flurry of numbers—some reliable, some unverifiable—onlycompounded the confusion. For parents desperate to protect their children,trustworthyanswerswerehardtofind.

AchildreceivesradiationscreeningatagymnasiuminFukushimaonMarch24,2011.AP

In an effort to avoid arousing fears, the government also deliberatelywithheldcrucialinformation—afactthatconfirmedthesuspicionsandinflamedthedistrustofmanywhentheomissionscametolight.

It wasn’t until June, for example, that officials publicly acknowledgedmeltdowns at the three reactors—information the government had possessedsince March 12, based on the off-site detection of tellurium-132, a fissionproductthatcouldonlyhavecomefromameltedcore.ByJuneitwasoldnewstoanyoneinJapanwhohadInternetaccessandcaredtosearchforFukushimaanalysisfromothersources.Moreover,theJapanesehadacknowledgedonApril12 that Fukushima Daiichi was a level 7 accident on INES, a ranking thatcertainly implied ameltdown.Theofficial disclosureof themeltdowns finallyarrivedshortlybeforedetailsaboutthemweretobereleasedataninternationalconference.

AndtherewastheJapanesemediaitself.It,too,operatedunderacloud.ReportsaboutFukushimaDaiichifrequentlycamecoloredwiththebuilt-inbiasesofthepublicationorbroadcastoutlet: fororagainstnuclearpower, fororagainst thepolitical party in office, for or against Japan’s powerful but faceless elitewhoinfluencedpolicybutseemedunaccountablefortheiractions.

Japan’snewsmediafordecadeshavefunctionedthroughasystemofpressclubswhose “members”—the journalists frommainstreammedia—work fromnewsrooms inside government offices and have ready access to the publicofficials and agencies they are assigned to cover. Nonmembers, who include

reportersworking for thegrowingnumberofWeb-basedor independent newsorganizations as well as freelance journalists, are left to their own devices,briefedlessfrequentlyandotherwiseisolatedfromthedailyofficialmedialoop.(Foreign journalists have their own press club, which accords them certainprivileges,buttheyalsoaregenerallylessconstrainedintheirrelationshipswithpublicandprivatenewsmakers.)

Criticsof thepressclubsystemhave longargued that it fostersa too-cozyrelationshipbetweenreportersandthosetheycover.Journalistscanbereluctantto challenge the official line for fear of alienating sources and losing access.Politicians and bureaucrats, for their part, know their pronouncementswill beduly reportedwithout countervailing views because that iswhat’s expected ofJapanese press club members. Aggressive investigative reporting, common inmanyothercountries,hasbeentheexceptionratherthantheruleformanyyearsinJapan.

The press clubs also can limit coverage of those who take issue withgovernment policies. Japanese antinuclear activist Aileen Mioko Smith, whoheads Kyoto-based Green Action, described the difficulty of attracting mediaattention tonuclear safety issues. “The Japanesepress club systemhasprovenvery effective at keeping nuclear news out of mainstream media,” she wroteshortlyaftertheaccident.“Ioftensay,‘Ifyouwanttomakesurethatyoudon’tgetanymediacoverage,gototheMETIpressclub.’”(METI, theMinistryofEconomy, Trade and Industry, oversaw nuclear safety until a governmentreorganizationaftertheFukushimaDaiichiaccident.)

Andthus,inthefranticdaysfollowingMarch11,wheninformationbecamethe coin of the realm, millions of Japanese felt themselves abandoned. Theinstitutions theyhad longdependedonand trusted—government,corporations,themedia—nowseemedineffectual,evensuspect,failingtodeliverasaresultofintent,ineptitude,orthesheerimmensityoftheunfoldingcrisis.

The experience left its mark on many Japanese. “There is a sense ofbetrayal,”saysDr.EvelynBromet,apsychiatricepidemiologistattheUniversityofNewYorkatStonyBrookwhoseresearchincludesthementalhealthimpactsof the Three Mile Island, Chernobyl, and Fukushima accidents. She visitedFukushima and examined detailed survey responses collected from evacuees.The responses reveal a high level of fear, anger, and emotional stress amongmany Japanese, she says. “There’s nobody that they trust any more forinformation.”

“Youshouldn’tassumethatpeoplecan’thandlethetruth,”saysBromet.“It

maybedifficulttoswallow,butit’sbettertobeopenandstraightwiththem.”During the Fukushima Daiichi accident, Japanese authorities ignored that

basic tenet of crisis management, concluded Japan’s Nuclear AccidentIndependent Investigation Commission in its July 2012 report. “[T]hegovernment chose to release informationpurely froma subjective perspective,ratherthanreactingtotheneedsofthepublic.”

JustastheNRC’stechnicalstaffrapidlygearedupinresponsetotheeventsatFukushimaDaiichi onMarch 11, so did the commission’s public informationarm. Although the accident was taking place halfway around the world, U.S.mediawouldhavequestions.

AsthehourspassedanddetailstrickledoutofJapan,itbecameincreasinglyclear that these distant events could have major implications for Americancitizensabroad,andevenathome, if radiationreleasesbecamesevereenough.Inadditiontothoseissues,thepublicaffairsstaffalsowassensitivetopossiblerepercussions for theU.S. nuclear establishment, onlynowgettingbackon itsfeetafteralengthy,involuntaryhibernation.

ConstructionhadresumedonthefirstnewAmericanreactorindecades,andthe NRC was well on its way toward approving combined construction andoperating licenses for four more reactors. The White House supported theexpansion of nuclear power in the U.S. energy mix, and the NRC wassystematically extending the licenses for aging plants, giving them anothertwentyyearsofoperation.Somewereevencallingthisanuclear“renaissance.”

Now,however,opponentsof thegrowingfootprintofnuclearpower in theUnitedStates,includingthosewhohadlongarguedthatitposedseriousriskstopublic health and safety, would be able to bolster their case by uttering oneword: Fukushima. ThreeMile Island had had the same impact three decadesearlier,andtheU.S.industrywasonlynowrecovering.

Onethingwascertainasthedisturbingreportscontinuedtoarrive:thiswasadeveloping drama that would dominate the twenty-four-hour news cycle fordays,ifnotweeks.Asaresult,someseriousmessagingwouldberequiredbyallsidesinthenucleardebate,andtheNRCwouldbeinthethickofit.

Shortlyafter5:00a.m.onMarch11,justaswordwasreachingtheUnitedStatesof the crisis in Japan, Scott Burnell of theNRC’sOffice of PublicAffairs e-mailedtheheadquartersoperationsofficeratWhiteFlintthathewasheadedin

towork.“Alwaysinterestingtowakeupandfindhugenewshasoccurred,”henoted.Atthispoint,hehadnoideahowhuge.

The job of public relations, whether performed for a public agency or aprivateenterprise,entailsdualmissions:toprovideaccurateinformationandtodeliver that information in the light most favorable to the presenter. Thosemissionscanconflict.AttheNRC,theOfficeofPublicAffairshastoperformaparticularly challenging balancing act. The agency is often caught in thecrosshairs between criticswho feel the agency is too lax on safety issues, too“pro-nuke,”andan industry thatpushesbackagainst regulations it seesas toostrictandhasthepoliticalmuscleinWashingtontogetitsway.

Although regulatory conflicts with industry and its allies do arise, theyusually occur under the media radar. As a result, the NRC is far moreaccustomedtodefendingitsperformanceagainstcriticsinthepublicsectorwhoclaim the commission is too lax.Andwhen those critics take aim, theNRC’spublicaffairsstafftendstocirclethewagonstoprotectitsown.

Fukushimawasn’t an accident in a backwater country; itwas occurring inhighly educated, science-savvy Japan, using technology and a regulatoryplaybooklargelyborrowedfromtheAmericans.Thirty-oneagingcarboncopiesof the reactors atFukushimaDaiichiwereoperating around theUnitedStates.Assurancesaboutreactorsafety,repeatedsooftenintheUnitedStates,hadalsobecome the mantra in Japan. Regulators and industry were cozy—anothercomplaintheardinbothcountries.Thoseconnectionswereprettyhardtoignore,andthenewsmedialatchedontothemalmostimmediately.

By10:30a.m.onMarch11,themediacallsande-mailswerepouringintotheNRC,andtheOfficeofPublicAffairshadalreadyassembleditsfirstsetoftalking points, a script of sorts to make sure everyone delivered the samemessage.AlistoflikelyquestionsandtheiranswerswaspreparedforChairmanJaczko,whowouldsoonbeinfrontofcamerasfieldingqueriesfrompoliticiansandthemedia.Thelistincludedtheobvious:

Q:“Canthishappenhere?”A:“TheeventsthathaveoccurredinJapanaretheresultofacombinationof

highly unlikely natural disasters. It is extremely unlikely that a similar eventcouldoccurintheUnitedStates.”

Q:“IsthereadangerofradiationmakingittotheUnitedStates?”A:“Giventhethousandsofmilesbetweenthetwocountries,Hawaii,Alaska,

theU.S.Territories,andtheU.S.WestCoastarenotexpectedtoexperienceany

harmfullevelsofradioactivity.”Q:“HasthisincidentchangedtheNRCperceptionaboutearthquakerisk?”A:“TherehasbeennochangeintheNRC’sperceptionofearthquakehazard

(i.e.,groundshakinglevels)forU.S.nuclearplants.Asisprudent,theNRCwillcertainly be looking closely at this incident and the effects on the Japanesenuclear power plant in the future to see if any changes are necessary toNRCregulations.”

Thoseweretheresponsesmarked“publicanswer”onthebriefingmaterials,withthisnoteattached:“Talkfrombutdonotdistribute.”Theywerenottobesharedwithout“explicit”permissionfromJaczko’soffice.AsfortheNRCstaffitself, the communications lidwasclamped tightly; all commentshad to comethroughtheOfficeofPublicAffairs.

Most of the Fukushima responses drafted for the chairman also containedwhat was marked as “additional, technical non-public information,” whichtendedtopaintasomewhatdifferentpictureofthesituation.Forexample:

Q:“Whathappenswhen/ifaplant‘meltsdown’?”A: Public answer: “In short, nuclear power plants in theUnited States are

designed to be safe. To prevent the release of radioactive material, there aremultiple barriers between the radioactive material and the environment,including the fuel cladding, the heavy steel reactor vessel itself, and thecontainmentbuilding,usuallyaheavilyreinforcedstructureofconcreteandsteelseveral feet thick.”Nonpublic addendum: “Themelted coremaymelt throughthebottomofthevesselandflowontotheconcretecontainmentfloor.Thecoremaymelt through thecontainment linerand release radioactivematerial to theenvironment.”

Q:“Willthisincidentaffectnewreactorlicensing?”A: Public answer: “It is not appropriate to hypothesize on such a future

scenarioatthispoint.”Nonpublicaddendum:“Thiseventcouldpotentiallycallintoquestion theNRC’sseismicrequirements,whichcouldrequire thestaff tore-evaluatethestaff’sapprovaloftheAP1000andESBWR[newreactor]designandcertifications.”

As to the question about the risk toU.S. residents from fallout, the publicanswer—theonethatdownplayeddangersbecauseofdistance—alsoincludedanon-public detail that didn’t sound quite so optimistic. “NRC isworkingwithDHS[theDepartmentofHomelandSecurity],EPAandotherfederalpartnerstoensuremonitoring equipment for confirmatory readings is properlypositioned,

basedonmeteorologicalandotherrelevantinformation.”It’s unclear for whom the “non-public” information was intended, but the

publicresponseswereutilizedrepeatedlyincomingdays.WhenJaczkotestifiedbeforetheHouseEnergyandCommerceCommitteeonMarch17,heofferedanearlyverbatimreassuranceonriskstotheUnitedStates:“Giventhethousandsof miles between Japan and the United States, Hawaii, Alaska, the U.S.territories,and theWestCoast,wearenotexpected toexperienceanyharmfullevelsofradioactivity.”

By Sunday evening,March 13, the media onslaught over Fukushima wasonlybuilding.“Thisisamarathon,nota50-yarddash,”wroteEliotBrennerofthe Office of Public Affairs to his staff about the flood of inquiries. Brennerremindedhistroopsnottostrayfromtheinformationcontainedinpressreleasesorofficialblogposts.“Whileweknowmorethanwhatthesesay,we’restickingtothisstoryfornow.”

ByMonday,March14,U.S. reporterswerebeginning tohome inona logicallocal angle to the events in Japan: the vulnerability of U.S. reactors toearthquakes.Theirinstinctsweregood.

Six years before, theNRChad begun a reviewof newdata from theU.S.GeologicalSurveyaboutseismicactivityinportionsofthecountryoncedeemedat low risk of damaging earthquakes, namely the eastern and central UnitedStates. Just as in Japan, advances in seismology now were raising questionsabout earlier risk assessments—assessmentsused to site, design, and constructAmerica’s reactors. The study, conducted in partnership with the nuclearindustry,wasknownbytheshorthandnameofGenericIssue199,orGI-199.

“Recent data and models indicate that estimates of the potential forearthquake hazards for some nuclear power plants in the Central and EasternUnitedStatesmaybe larger thanpreviousestimates,” theNRCsaid ina2010documentdescribingthestudy.Andthat“couldreduceavailablesafetymargins”atoperatingreactors.

Reactors are designed to shut down automatically when a certain level ofgroundmotionisdetected, justas thereactorsdidatFukushima.(Those levelsaresetindividuallyforeachplant,basedonhistoricalearthquakedata,whichinthe United States—unlike Japan—dates back only a century or two.) Othersystemsneeded tomaintain the reactor in a safe state, suchas coolantpumps,havetobeabletoworkafteraso-calledsafeshutdownearthquake.Butwhatif

thatgroundmotionismuchstrongerthandesignershadestimated?Wouldalltherequiredsystemsstillwork?Orcouldvitalequipment failandcorecoolingbelost? “Updated estimates of seismic hazard values at some of the sites couldpotentiallyexceedthedesignbasis”fortheplants,theNRCstudyfound.

TheGI-199findingsdidn’tgainmuchmediaattentionuntilthemagnitude9.0quakehitnortheasternJapan.For journalists, thefindingsrepresenteda

Fukushima follow-up that readers and viewers in the United States couldidentify with. Some at the NRC weren’t happy with the newfound mediainterest.“Frankly,itisnotagoodstoryforus,”wroteAnnieKammerer,aseniorseismologist and earthquake engineer at the NRC, shortly after midnight onMarch15.

Thedaybefore,BillDedman,areporterforNBCNewsandmsnbc.com,hade-mailedtheNRCabouttheseismicsafetydata.Dedman,aveteraninvestigativereporter,hadtrolledthemassivepubliconlinearchivesmaintainedbytheNRCand come across the GI-199 document titled “Implications of UpdatedProbabilisticSeismicHazardEstimatesinCentralandEasternUnitedStatesonExisting Plants.” Appendix D of the report caught his eye. The appendixcontainedrevisedassessmentsoftheriskofearthquake-inducedcoredamageatninety-six reactors in the eastern and centralUnitedStates.Nowhe had somequestionsfortheNRC.

Hearing nothing back from his initial e-mail inquiry, Dedman sought outsome math professors to help ensure that he understood the complexcalculations.EarlyonMarch15hebypassedtheOfficeofPublicAffairsande-mailedtheauthorsoftheNRCreport,outlininghowheinterpretedthedata.“I’dlike tomake sure that I accuratelyplace in layman’s terms the seismichazardestimates,” he explained. Dedman also requested information about westernreactorsnotonthelist,whichtheNRCprovidedtohimthatafternoon.

Early the next morning, Dedman’s article, “What are the odds? US nukeplantsrankedbyquakerisk,”waspostedonthemsnbc.comwebsite.Basedonthe NRC’s estimates, the reactor at highest risk of core damage from anearthquakewasnotDiabloCanyonorSanOnofre, locatedinearthquake-proneCalifornia, but rather Indian Point Unit 3, sitting thirty-five miles north ofManhattan.

TheNRC’simmediatereactionwastodiscreditDedman’sstory,evenwhilethecommission’sexpertswereporingover it.ScottBurnelle-mailedDedman:“Iunderstandyou’remakingahonestefforttoconveythelatestresearch,butIhave no doubt the technical staff are going to have significant problemswith

howyou’vepresentedit.”Burnellthene-mailedKammerer:“Apartfrom‘you’retotallyoff-base,’whatspecifictechnicalcorrectionscanweaskfor?”

AsothermediacallsandinquiriesaboutFukushimacontinuedtopileupintheOfficeofPublicAffairs, themorningofMarch16wasspentattempting toimpugn Dedman’s report, which Burnell characterized as “jaw-flapping.”“Folks,” he wrote at midmorning to the technical staff assigned to scrutinizeDedman’s analysis, “the expected calls [about the story] are coming in—WeneedabetterresponseASAP!”TheNuclearEnergyInstitutewasalsourgingtheNRCtoreply.

Thestorycreatedanimmediatestir, triggeringinterest fromtheAssociatedPress, CNN, theNew York Times, New York’s congressional delegation, theCongressionalResearchService, and reporters around the country. (Soon afterDedman’sreportappeared,NewYorkgovernorAndrewCuomoorderedasafetyreviewoftheIndianPointplant,inpartbasedonthenewriskdata.)

About12:30p.m.onMarch16,BenjaminBeasleyof theNRC’sOfficeofNuclear Regulatory Research e-mailed Burnell that the experts had come upempty-handed. “I have received no concerns or corrections regarding themsnbc.comarticle,”wroteBeasley.

WhattheNRC’spublicaffairsstaffmostobjectedtowasthatDedmanwenta step beyond the information they had provided: he gave it meaning for ageneral audience. By sorting through the commission’s voluminous data,Dedman had arrived at risk rankings for the nation’s 104 operating reactors.(The NRC had provided the raw data for each reactor, listing the plantsalphabetically but not taking the final step of ranking them in order of risk,consistentwithitslong-standingpracticeoftryingtoavoididentifyingthemostdangerousplants.)That,DedmansaidinresponsetocomplaintsfromtheNRC’sEliot Brenner, is like the U.S. Census Bureau publishing poverty figures formetropolitanareasbutnotthenidentifyingthepoorestofthepoor“lestanyonefeel bad.” It’s left to reporters to inform the public of the numbers’meaning.“That’sourjob,”DedmantoldBrenner.

Inaconversationlongafterthekerfuffle,DedmanblamedtheNRC’sOfficeofPublicAffairsforcaringmoreabouttheagency’simagethanaboutinformingthepublic.Byattemptingtodiscreditthemessenger,versusacknowledgingthepublicvalueoftheinformation,“theylostcredibilityfortheirorganization.”

As the number of Japanese leaving their homes continued to climb, hastily

opened shelters beyond the evacuation zones began to fill. These nuclearnomads, who fled with few possessions, were now crowded into makeshiftquarters thatoften lackedadequateheat, food,water,or sanitary facilities.Forthem,theimpactondailylifewasimmediateandburdensome.

Manyhadno ideawhytheir liveshadbeen turnedonend.Withoutpower,theabilitytoobtainnewswasgone.2Whiletherestoftheworldwaswatchingthenuclear crisisunfold, thosemost threatenedby thedeterioratingconditionsinsidethereactorswerelivinginaninformationbubble.

Asthedisplacedpopulacewaitedforexplanations,theevacuationzoneskeptexpandingoutward. In thosefirst tumultuousdays,someevacueeswereforcedto relocate six times ormore, fleeing ever farther from the reactors, their fewbelongings stuffed in bags or tucked under their arms.Others, however,wereforgotten,withfatalconsequences.

Evacueescrowdedintoschoolgymnasiumsandotherpublicbuildings,wherelivingconditionswereharshand privacy nonexistent.Many of those who fled their homes had little or no idea why they had beenorderedtorelocate.Asconditionsatthereactorsworsened,largenumbersofevacueeswereforcedtomoveseveraltimes.VoiceofAmerica

HoursafterthesecondevacuationnoticewasissuedearlyinthemorningofMarch 12, preparations got under way to move the two hundred and nineambulatorypatientsandstaffoutofFutabaHospital, locatedabout threemiles(five kilometers) from the plant.Left behind, however,were one hundred andthirtybedriddenhospitalpatientsandninety-eightresidentsofanearbynursinghome.TheSDFreportedlywereenroutetotransportthem.Owingtoaseriesofbureaucraticerrorsandcommunicationmix-ups,thetroopsdidn’tarrivefortwo

days,duringwhich timethefacilitieshadnopowerorheatandcaregivershaddeparted.Bythen,fourpatientsweredead.Whenthetroopsfinallyshowedup,the patients began a grueling odyssey, spending hours on the road before thetroops found a shelter thatwould accept them.Fourteenmore died during thetrip. But thirty-five patients were accidentally left behind, forgotten and notrescueduntilMarch16.Bytheendofthatmonth,officialsreportedthatamongtheFutabaevacueesatotaloffortypatientsandtennursinghomeresidentshaddied.

In a society accustomed to order and predictability, the accident responseincreasingly seemed chaotic and leaderless. The confusing and incompleteinformation coming from the government offered little guidance for JapaneseseekingtounderstandthethreatfromFukushimaDaiichi.Later,officialswoulddefendtheirwithholdingoffactsbyclaimingtheydidnotwanttoalarmpeople.Butformany,thisshowofpaternalismwastantamounttoputtinglivesatrisk.

EventsinthescenicmountaintownofIitate,likethebungledevacuationofFutaba Hospital, came to symbolize the breakdown of the government’sresponseandtheconsequencesforthoselefttofendforthemselves.

FollowingtheexplosionatUnit3onMarch15,theprevailingwindsshifted,carryingradiationtothenorthwesttowardvillagessuchasIitate,populationsixthousand, located about twenty-five miles (forty kilometers) from FukushimaDaiichiandthuswelloutsidetheofficialevacuationzone.Aneveningsnowfallblanketed the region,carryingwith itparticlesof radioactive iodine, tellurium,andcesium.SPEEDI,thesophisticatedcomputertrackingsystem,hadpredictedthatIitateandthetownofNamiewereinthepathoftheplume,buttopofficialsinTokyodismissedthedataasunreliable.NearlytwoweeksaftertheMarch15release, government officials realized that Iitate and its neighbors had become“hot spots,” with areas of radiation far above background levels. As officialsdebated whether evacuation was warranted, the residents of Iitate stayed put,caringfortheirfamilies,theirfarms,andtheirprizedcattle.

AmapoftheemergencyresponsezonesnearFukushimaDaiichiestablishedbytheJapanesegovernmentasoftheendofApril2011.Theregionmarked“deliberateevacuationarea,”extendingnorthwestoftheplanttoIitate,wascreatednearlysixweeksaftertheaccidentbegan.Authoritieshadbeenforcedtoconfrontthefactthatwindsandprecipitationhadspreaddangerouslevelsofradioactivecontaminationwellbeyondthetwelve-mile(twenty-kilometer)evacuationzoneestablishedsoonaftertheaccident.GovernmentofJapan

All thewhile, radiationdata fromawide radiusaroundFukushimaDaiichiwas appearing online, showing elevated levels in Iitate and other areas to thenorthwestofthereactors.Basedonthatinformation,somelocalresidentsgrewalarmed about the lack of protectivemeasures, expressing their frustrations toanyonewhowould listen. “We have been sacrificed so that Tokyo can enjoybright lights,” a tobacco farmer told aNewYorkTimes reporter, visiting IitatethesamedayasanIAEAinspectionteam,dressedinprotectiveclothing,arrivedto take radiation readings among farmers working the fields. Even after thediscoveryofthehotspots,thegovernmentfailedtoact.Later,oneIitateresidentexpressed what many were thinking about their government: “Do they reallyvalueourlives?”

Japaneseauthorities,however,continuedtodragtheirfeet.Finally,onApril22,Tokyoordered theevacuationofIitateby theendofMay.Whentheorder

came at last, the residents of Iitate were confronted with decisions bothpragmatic andpoignant.Some residents, especially thosewithyoungchildren,hadalreadyfled.Apriesttoldavisitor,“Anyonewhothinksaboutthefuturehasleftourvillage.”

Forothers,severingtieswasawrenchingexperience.Theyalreadyhadbeenexposedtotheradiation;hadthedamagealreadybeendone?Manylivedonlandthathadbeenintheirfamiliesforgenerations;couldthissoilbefarmedagainintheir lifetimes? Their children’s lifetimes? And what of their beloved cattle,considered almost like pets?Photos of abandoned livestock, dead or dying, inevacuationzoneselsewherehadbeenpublishedaroundtheglobe.

Knowingthatnoonewouldbuytheiranimalsforfearofcontamination,andnot wanting them to suffer, Iitate’s farmers saw no choice. Before departing,theyslaughterednearlythreethousandcattle.Soon,Iitate,whichtheyearbeforehadbeendeclaredoneof themostbeautifulvillages in Japan,becameaghosttown.

6

MARCH19THROUGH20,2011:“GIVEMETHEWORSTCASE”

OnMarch19,eightdayshadpassed since themassive tsunami surgedupandswampedtheFukushimaDaiichisite.Ironically,whatthecripplednuclearplantneededmostnowwaswater.Tonsofit.

InsidethecoresofreactorUnits1,2,and3,waterlevelshaddropped—theresultofheatboilingawaycoolantandofintentionalreleasesofsteamthroughsafety relief valves to lower pressure so thatmakeupwater could be injected.Eventhoughseawaterwasbeingsteadilypumpedintoallthreereactorvessels,instrument readings showed that the intensely radioactive fuel in all of themremainedexposed;inUnit3byasmuchassixandahalffeet,byslightlylessintheotherunits.1Theamountofwaterinthespentfuelpools,especiallyinUnit4,wasuncertain(andasubjectofcontinuingdebate).Onethingwasobvioustoeveryone, however:water provided at a sufficiently high rate offered the besthope that operators might be able to lower the temperature within each corebelow its boiling point, prevent further radioactive releases, and wrestle thecrippledmachinery intosomesortofeventualshutdown.At the least, itwouldbuythemsometime.Forthepasttwodays,Self-DefenseForcesandriotpolicehad been spraying water on and, they hoped, into the Unit 3 spent fuel poolusinghelicopters,high-volumewatercannons,andfireengines,eachcapableofdeliveringsixtonsofwaterperhour.Thesewereaugmentedbyahigh-pressurepumperprovidedbytheU.S.military.AswaterhitthehotUnit3drywallhead,alargesteamplumeshotskywardthroughthegapingroof,aneventcapturedbyphotographers.WhentheNRC’steamatWhiteFlintsawtheimages,theywereconvinced that the pool, along with the Unit 4 fuel pool, was dry. TEPCOvehementlydisagreed,however, andhadnotyetattempted to injectwater into

Unit4.AlsomurkywasthestatusoftheUnits1and2spentfuelpools,whichlike

theotherswereperchedhighabovethecontainmentvessels.Theconcrete-and-steelroofatoptheUnit1reactorbuildinghadcollapsedintothepoolduringtheexplosion there, possibly preventingwater from reaching the pool, or at leastfilling it with debris. But the heat load from the fuel in the Unit 1 pool wassmaller than theothers, so it appeared toposea less immediate threat.Unit2,whichhadahigherheatloadthanUnit3,stillhadaroof,soitwasimpossibletoseeinside.However,justdoingthemath—poolvolume,heatofspentfueltimesdayswithout power to provide circulation and cooling—made it clear that theUnits1and2spentfuelpoolswouldsoonneedcoolingrestoredortheywouldalsobeendangered.

Japan’sSelf-DefenseForcesandriotpoliceemployedfiretrucksandwatercannonsinanattempttocoolUnit3’sspentfuelpool.Evenafterthetopofthereactorbuildinghadbeenblownoff,itwasunclearhowmuchwaterhadreachedthepool.TokyoElectricPowerCompany

Adding water to the pools was also critical to reducing radiation levelsaround the plant site.Thewaterwould provide a vital shield against radiationfrom the spent fuel; however, workers still would face a threat from theradioactivedebristhrowntothegroundbetweenUnits3and4bythehydrogenexplosions.Thatandthe“shine”beamingfromtheopenpoolsrenderedmuchofthe area off limits. A worker on a fire truck driven close to the reactors hadpicked up ten rem of radiation in just two minutes—double the maximumexposure thatworkers inU.S. nuclear plants are allowed to receive during anentireyear.

Atruckknownasakirinorgiraffe,normallyusedtopumpconcreteathigh-riseconstructionsites,deliverswatertotheUnit4spentfuelpool.Thistruckwassoonjoinedbyothers.TokyoElectricPowerCompany

The ability to deliver water to the pools did not improve untilMarch 22,when a giant truck with a fifty-eight-meter articulated boom arrived. It couldprecisely direct up to 120 cubic meters of seawater per hour (about 32,000gallons)high into the fuelpools, a farmoreeffectiveaid than theaerialdropsfromhelicoptersorthefirehosesfromgroundlevel.Thetruckcouldbedrivenin,parked,andthenoperatedremotely,meaninghumanradiationexposurecouldbekept toaminimum.Thesingle trucknow inpositionatFukushimaDaiichiwould eventually be joined by trucks from China, Germany, and the UnitedStates.

Althoughgettingwatertothereactorsandpoolswasahighpriorityforthe

Japanese, they were also devoting considerable time and effort to restoringpower toFukushimaDaiichi.Workerswereslowlybringing innewlines fromtheoutside.Theyfinallyrestoredoff-siteelectricitytoUnit2onMarch20,andgradually brought power to the remainingunits over thenextweek.However,the NRC crew had its doubts about the Japanese push to regain electricity.Connecting cableswas one thing, but getting electricity flowing to equipmentthathadbeenfloodedwasquiteanother.

“Wedon’t seewhere the power thing is any solution at all,”ChuckCastotold his colleagues fromTokyo. In all likelihood,water damage had renderedsomeofthecircuitryandinstrumentationinsidethereactorsandcontrolroomsunusable.(Asitturnedout,theywerepartlyright.EvenaftertheUnit2powerpanelwasenergized, it tookanother sixdaysbeforecrewscouldeven turnonthe lights in the main control room. But the availability of off-site powereventuallyenabledworkers to switch fromfireengines toelectricallypoweredtemporarypumpsfordeliveringwatertothereactorcores.)

Aweekaftertheaccident,radiationlevelswerestillsohighthatsendinginworkers to make the necessary connections and repairs to the installedequipmentwouldbedifficultifnotimpossible.Noonehadyetevenbeenabletogetcloseenoughtothedamagedbuildingstomaptheareasofhighestradiation,vital information ifhumanworkerswere tobedispatched to thesite.Readingsfromthefiretruckindicatedthoseradiationlevelsweredeadly,however.

OnthephoneCastosoundedexhausted—andexasperated.HiscolleaguesatWhite Flint knew he was running full-out. “Right now he’s basically a 24/7individual,”JimWigginsexplainedinabriefing.“He’sgettingverylittlesleep,andhe’s holdingup, but not for long.”Casto’s days—andnights—were filledwithmeetings,andhisto-dolistneverseemedtogetshorter.TheU.S.Embassystaffwas struggling to devise a contingency plan in case radiation levels roseenoughtothreatenTokyoandtheembassyitselfhadtobeevacuated.Castowasbeingpressuredforaccidentscenariosanddosecalculationshedidn’thave.

NordidtheNRCatWhiteFlint,forFukushimawasexposinghugegapsintheagency’sability toprovideuseful advice in real time forprotectingpeopleduringanuclearaccident.ThedecadesofstylizedaccidentcomputersimulationswereprovingoflittlehelpininterpretingtheeventsthathadalreadyhappenedinJapan, much less making credible predictions. As a result, everyone wasscrambling to come up with high-confidence assessments of how bad theaccidentwasandhowmuchworseitcouldget.

MartyVirgilio,whowasmanningtheovernightshiftatWhiteFlint,assured

Casto that the NRC’s Protective Measures Team was working on the doseestimates. “We’re developing calculations to seewhat we thinkwould be theworst case and the best case with respect to radiation levels in yourneighborhood,”Virgilioexplained.“Thatwouldbefantastic,”repliedCasto.Theteam was aware that the French Embassy, concerned about the levels ofradioactive iodine reported in Tokyo, had recommended that French nationalsevacuate theTokyo region.AmbassadorRoosmightwell bewondering if theFrenchknewsomethingthathedidn’t.

Relations between the Japanese government and the Americans sent toTokyo to assist with the accident response were occasionally distant andstrained.ThisclearlyfrustratedtheNRCcrewattheembassyaswellasbackatheadquarters. “[T]he political dynamic and the . . . organizational dynamic, isjust, you know, unfathomable,” said Casto over the phone. He chafed at theformalities of some meetings—“it’s probably one of those pretty-face thingsagain,”hesaidofonecomingup.Theseformalities,tohismindatleast,ateupvaluabletime—andtheJapanesedidn’thaveanytospare.

As for TEPCO, dialogue between the utility and the NRC team remainedpractically nonexistent. And when the NRC experts finally did get theopportunity to sit down with company representatives, the talks weren’tespeciallyproductive.“[T]heysaidtheydidn’tneedanyhelpandeverything’sinfullcontrol,underfullcontrol,”JohnMonningersaid.

WhiletheJapanesehadneveranticipatedanaccidentascomplexastheoneunfoldingatFukushima,neitherhadtheNRC.Thisdidn’tstoptheagencyfromengaginginbackseatdriving,though.Monningertookissuewithwhathesawastheutility’snarrowfocusindealingwithanunfolding,multiprongedcrisisthatwas far from under control. “They have one priority: Unit 3,” he toldWhiteFlint.“Andoncetheygetdonewiththat,they’lldeterminethenextpriority.”

FortheU.S.team,therewasnoshortageofpriorities—andthelistseemedtoexpandwitheachphoneconversation.

Soon,themostcontentiousissuetoconfronttheNRCwouldsurfaceasthecrisisworsened.High-levelofficials inWashingtonwanted toknowone thing:howbadcouldthisget?FortheNRC,thatwasaquestionfraughtwithallsortsof implications. The agency had spent years downplaying the risks of nuclearaccidents,contendingthatareal“worstcase”couldneverhappen.Now,itwasbeingaskedtoassumetheopposite.

ThelistoffederalagenciesworkingontheresponsetoFukushimaintheUnitedStatesandJapanincludedfamiliarnamesliketheDOE,theDepartmentofState,and the EPA. But it also included a small cadre of government entities fewAmericans have ever heard of, including the National Atmospheric ReleaseAdvisory Center. The center, known as NARAC, uses computer models andgeographicdatatomapthespreadofhazardousmaterialsthatgetreleasedintothe atmosphere. Its predictions are intended to help decision makers in anemergency,anditsmodelswerecapableofpredictingthemovementofradiationplumeswithmoreaccuracyandtoconsiderablyfurtherdistancesthantheNRC’sRASCALcode.

At the moment, experts across the U.S. government were grappling withthese questions: just what could be the worst-case scenario, and how muchradiationmight escape fromFukushimaDaiichi if that scenariooccurred?TheanswerhadramificationsnotonlyforJapanandtheAmericancitizenstherebutpotentially for theUnited States itself. Tomake those predictions, the expertsfirsthadtoagreeonwhat’sknownasasourceterm,anassessmentofhowmuchradioactivematerialcouldactuallybereleasedfromthereactorsandfuelpoolsintotheenvironment.Thetypesofmaterialandthetimingofthereleaseswerealsokeyinputsforpredictingwheretheradioactiveplumeswouldtravelandthenature of the damage they could cause. The bottom line issue for the U.S.government was this: what threats would such a release pose to Americans,whetherathomeorabroad,andwhatmeasureshadtobetakentoprotectthem?Without a more precise understanding of the source term, the answer to thatquestionwouldremainfrustratinglyelusive.

SOURCETERMEXPLAINED

Sourcetermdefinesthetypesandamountsofradioactivematerialreleasedduring a nuclear plant accident. The source term depends on manyvariables,includingtheinitialamountofradioactivematerialinthenuclearfuel,howmuchofthatradioactivitygetsreleasedfromdamagedfuel,howmuch of that radioactivity is retainedwithin the plant, and howmuch isreleased to the environment, where it can be transported to downwindcommunities.

Highlyradioactivematerialslikeiodine-131andcesium-137,knownasfissionproducts, areby-productsof thenuclearchain reaction thatdrivesthenuclearengine.Anoperatingnuclearreactorcorecontainsamixtureofdozens of different radioactive isotopes. The quantities of these isotopesdepend on the power level of the reactor and the length of time that thereactorhasoperated,amongotherfactors.

Radioactive materials are unstable and release radiation seeking toreacha stable form.The time it takes forone-halfofagivenquantityofradioactive material to decay—called the half-life—varies from a merefractionofasecondtomillionsofyears.Inareactoraccident, thelongertheonsetofreactorcoredamageisdelayedaftershutdown,themoretimeis available for radioactive materials with short half-lives to decay intostablematerials,therebyreducingthesourceterm.

Different isotopes have different radioactive properties, whichdeterminetherelativehazardstheyposetotheenvironmentandtohumansandotherorganisms.Certain isotopes,suchasplutonium-239,emitalphaparticles,whichcannotpenetrateskinbutareparticularlyhazardousinsidethe body; thus alpha emitters are very dangerous if inhaled or ingested.Others, like strontium-90, emit beta particles,which are somewhatmorepenetratingthanalphaparticlesbutstilldomoreoftheirdamageifemittedwithinthebody.Incontrast,high-energygammarayspenetratedeeply,andhencegammaemitters likecesium-137candotheirdamagefromoutsidethebody.

Different radioactive isotopes also have different chemical forms,whichdeterminehowtheybehavewithin thereactor, in theenvironment,andinlivingthings.Forexample,beta-emittingiodine-131becomesagasat ambient temperature, can be transported large distances in theenvironment,andif inhaledor ingestedconcentrates in the thyroidgland,where it candeliver ahighdose.Luckily, though,with a relatively shorthalf-lifeofeightdays, itdoesnotpersist in theenvironment. Incontrast,plutonium-239remainssoliduptoveryhightemperaturesandisnoteasytodisperse, butwith a 24,000-year half-life and a tendency todeposit inliver and bone, it is very persistent in the environment or in the humanbody.

Thesepropertiesdetermine the relativehazardsof thedifferentstagesof a radiation release. In the early stages of the accident, people can beimmersedinandinhaleairborneplumes.Inthelaterstagesoftheaccident,

aftertheplumehaspassed,peoplecanbeexposedtocontaminationontheground and other surfaces and in food and water. Contaminated dustparticlescanalsobecarriedupwardbyaircurrentsandinhaled.

Whenanaccidentcausesthefuelrodcladdingstooverheatandbreakbutisstoppedbeforethefuelpelletsaredamaged,thereleaseislimitedtotheradioactive gases trapped in the space between the pellets and cladding,including noble gases, iodine-131, and cesium-137. If overheating is notstoppedintime,thefuelpelletsthemselvescanbreakapart,allowingsomeoftheradioactivematerialstrappedwithinthepelletstobereleasedalongwiththeradioactivegases.Ultimately,thepelletsthemselvescanmelt,andrelease an even wider range of isotopes, including plutonium-239 andamericium-241.Thegreater the fractionof thecoredamaged, thegreatertheamountofmaterialavailableforrelease.

Afunctioningreactorcontainmentisdesignedtoallownomorethanasmallfractionoftheairborneradioactivitywithinthereactor—lessthan1percent—frombeing released. If containmentventing isnecessary, filterscould be used to prevent radioactive materials from escaping into theenvironment.However,ifthecontainmentbarrierisbreachedorbypassed,afargreateramountofradioactivitycanescape.

Evenifthecontainmentfails,determiningtheactualamountthatmaybe released over time is difficult because radioactive gases and particlesreleasedfromdamagedfuelmaycooldownand“plateout”—thatis,stickto—various surfaces and be retained within the plant. But even thesematerialsmayeventuallyheatupagainandescape.

Oncethesourcetermisdeveloped,theweatherconditionsaredefinedandpopulationsatriskareidentified.Basedonthisinformation,thehazardfromradioactivematerialsescapingfromanuclearplantcanbeestimated.But other variables also play a factor. Wind may blow the radioactivecloud toward or away from densely populated areas. A city forty milesaway fromadamagedplantmaybeatgreater risk thancloser cities if itstartstorainastheplumepassesoverhead.

Although the source term is used in estimating the risks, the actualhazard depends on questions that cannot be definitively answered duringan accident or even long afterward.When was the fuel damaged? Howmuchfuelhasbeendamaged?Towhatextenthasthefuelbeendamaged?How much radioactive material released from damaged fuel has been

retainedintheplant?Artfulscienceisappliedtoestimatethesourcetermbasedonthemostlikelyanswerstotheseimportantquestions.

President Obama, in an address to the nation on March 17, offeredreassurances.“WedonotexpectharmfullevelsofradiationtoreachtheUnitedStates, whether it’s theWest Coast, Hawaii, Alaska, or U.S. territories in thePacific,”hesaid.“ThatisthejudgmentofourNuclearRegulatoryCommissionandmanyotherexperts.”Butbehindthescenes,thoseexpertswerestilldebatingthenumbers,evenasconditionsinsidethereactorsandfuelpoolswereunclear.

Radiationmonitors atCalifornia’sDiabloCanyon and SanOnofre nuclearplantshadalreadypickedupreadingsofiodine-131justslightlyabovewhattheNRC described as “the minimal detectable activity level.” It presumably wasblowing in from Fukushima, 5,400 miles away. If these levels continued toincrease, there was a chance that the president would later have to reversehimself and order countermeasures like banning milk shipments from certainareas.Thatcouldresultinamajorlossofconfidenceamongthepublic.

Among the scientists and administrators, disparate views on the radiationthreatabounded,apparentlyhashedoutintheconfidentialityoftheWhiteHouseSituationRoom,whereofficials fromahostof agenciesgathered.Discussionsalso were going on at the U.S. Embassy in Tokyo. There had been internaldisagreementsinbothplacesovertheNRC’srecommendationtwodaysearlierfor the fifty-mile evacuation for U.S. citizens in Japan. Now, based on aerialmeasurements between thirteen and twenty miles northwest of the reactorsshowing exposure rates above one rem over four days, the EPA evacuationstandard, the NRC was confident it had made the right call. But the agencycontinued to take heat for the decision. On March 18, the Nuclear EnergyInstitute contacted the NRC to complain that the fifty-mile evacuation couldundercutthepublic’sfaithinthiscountry’sten-mileemergencyplanningzone.

Back atWhite Flint, Trish Holahan, director of security operations at theNRC’s Office of Nuclear Security and Incident Response, and her colleagueswereporingoversomealarmingdoseestimatesforU.S. territorythat theyhadreceived fromNARAC.Because theNRC’sownRASCALmodelhad limitedrange, the agency had to rely on NARAC to go farther using its moresophisticatedplume transportmodels.Employingsource termssuppliedby theNRC, NARAC’s models were finding that thyroid doses to one-year-oldchildren in Alaska could be as high as thirty-five rem—seven times the EPA

dose threshold that would trigger the need for countermeasures such aspotassiumiodideadministration.

ButtheNRCthoughtthatsomeofNARAC’sassumptionsseemedabitfar-fetched. The potential radiation exposure of grazing dairy cows in Alaska inmid-Marchwasoneexample.“Thecowsarekeptindoors,”HolahantoldJaczkooverthephone.“Eventhewatersupplyis internalbecausethey’renotoutside.Soweeliminatedthatdose.”

TheassumptionofgrazingcattleinAlaskainwintertimewasjustoneaspectof a larger issue that the NRC was trying to grapple with: theWhite Houserequestfora“worst-case”assessment.Fromtheperspectiveofthepresident,thisapproachmadesense:ifevenunderthemostpessimisticassumptionstherewaslittle risk to the American public from Fukushima, then the president couldcontinuetoprovidereassuranceswithoutfearthathewouldbelateraccusedofunderestimatingthethreat.

JoiningtheWhiteHouseinpushingfortheworstforecastwasAdmiralMikeMullen,chairmanoftheJointChiefsofStaff.“Ihavebeentaughtbymynuclearpowercommunitymywholelifetoplanaroundtheworstcasepossibilities,”hewrote to Obama’s top science advisor. “This in great part had a lot to do inkeepingour[Navy]plantssafe.”

However, theconceptofaworst-casescenariowasanathematotheNRC’swayofthinking.Fordecades,NRCregulationsandpolicieshadbeenexplicitlydesigned toavoidaccounting forworst-case scenarios,whichwerebelieved tobe so unlikely as not to merit consideration. Calculating a worst-case sourcetermfellintothatsamecategory.

TheNRChad alreadyventuredoutside its comfort zonewhen itmade therecommendationforafifty-mileevacuationaroundFukushima,basedonsource-termassumptionsthatitjudgedveryunlikely.Nowitwasaskedtoconsiderevenmoreextremecases.

TheNRCinsteadpreferredtofocusonwhat itconsideredmorerealisticor“best estimate” scenarios.TheNRChad just spent severalyearsona researchproject called State-of-the-Art Reactor Consequence Analyses meant to calmpublic fears about nuclear power by calculating “realistic” severe accidentsourceterms.Thosenumberswerelowerthanpreviousestimates,andtheNRCwaspleasedwiththeinitialfindings.Butnow,whenareasonedperspectivewasneeded more than ever—at least in the eyes of the NRC—the White HouseappearedtobeaskingtheNRCtothrowitsapproachoutthewindow.

TheWhiteHousewantedtheNRCtoprovideasourcetermtoNARACthatassumedthat100percentofthefuelinthecoresofUnits1,2,and3andinthespentfuelpoolsofUnits1,2,3,and4hadmelted,withtheUnits1–3primarycontainments failing completely so that the resulting radiation from all sevensourceswouldbereleasedintotheenvironment.

Jaczkowasfrustratedbythisrequest.Hequestionedwhether theNRCwasbeing asked to hypothesize an accident that was in fact impossible—one thatwould essentially vaporize all the cores and spent fuel and eject it all into theenvironment.“[O]bviously, there’saphysical realityat somepoint thatcertainthingsjustcannothappen,”Jaczkosaid.Asbadasthisaccidentwas,therewerenoplausiblephysicalmechanismsthatcouldvaporizetheentirecoreofalight-waterreactorlikethoseatFukushima.EvenatChernobyl,amoreunstabletypeof reactor that experienced a runaway chain reaction and massive steamexplosions,mostofthecorematerialremainedwithinthereactor.

“[T]here’swhat’sworstcaseandthenthere’swhat’spossible,”JaczkotoldHolahanandtheteamatWhiteFlint.“SoIthinkwhatweshouldproduce[is]aworst-case[scenario]that[is]actuallypossible.”Instead,hesaid,theNRCwasbeingaskedtoenvisionthenuclearequivalentofa“meteorhittingtheearthatthe same time as an asteroid strikes.” Holahan agreed to go back and conferagainwiththereactorsafetyexpertsandcomeupwithsomenewanalyses.

Earlierthatafternoon,Jaczkohadspentforty-fiveminuteswiththeJapaneseambassador,makingacombinedcondolenceandbusinesscallattheembassyonMassachusetts Avenue. The NRC crew hoped the visit might facilitatecommunications between Washington and Tokyo. “We have a tremendousopportunityherenow,”Jaczkohadtoldhisteambeforeheadingtothemeeting.“We have an ambassador who basically wants to be helpful and can passinformationtohelpmovealogjamifnecessary.”

ChuckCasto,backfromameetingwiththechairmanofTEPCOandtheutility’schiefnuclearofficer,calledhiscolleaguesatWhiteFlintatabout9:00p.m.onMarch18togivethemanupdate.“Itwasacordialmeeting,”hesaid.Incontrasttothefewpreviousencounters,thistimeTEPCOexecutivesaskedforhelpfromtheAmericans.

AlthoughtheNRCwasstillfocusedonfindingawaytocoolthespentfuelpools,TEPCOwasmoreworriedabout the reactors themselves—inparticular,the accumulation of salt inside them. As the fire trucks kept pumping inseawater, large amountsof saltwerebuildingup in thebottomsof the reactor

vessels,potentiallyblockingtheflowofthewaterandinterferingwitheffortstocool down the fuel. In addition, seawater ismore corrosive tometal than thefreshwaterthereactorswerebuilttouse.ForcedtouseseawateratFukushima,the Japanese wanted to consult about the problems it would create for themdowntheroad.Theywerenowaskingforassistance.

Jaczko was listening in. “Do you think that project team should be NRCpeople or somebody else, like maybe INPO or something like that?” CastoagreedthatboththeNRCandtheInstituteofNuclearPowerOperationsoughttoget involved, alongwith theDOE,which has expertise in radiation doses anddecontamination.

“I think this is amajor change in themission,” Casto told Jaczko. “Sir, Ibelieve that they are looking to us for solutions. . . . I think they were . . .desperateforoptions.”

Jaczko’sreference toaheightenedindustryrole in theU.S.response to theaccidentwasnothypothetical;thedetailswerebeingfinalizedevenasthemenspoke.The expert industry groupwas set to gather atNRCheadquarters. ThewearyWhiteFlintteamhopedthefreshtroopsmightshiftsomeoftheloadoffthe NRC’s shoulders; with luck, the involvement of industry might evenencourage TEPCO and Japanese officials to be more forthcoming withinformationandtoacceptmorehelp.

Participants with special expertise, such as GE, which had designed theFukushima Daiichi reactors, would be asked to provide guidance on gettingwater intothefuelpools,forexample.Other industryrepresentativeswouldbeinvitedtohelpdeviseshort-andlong-termsolutionsinJapan.

Itwasnotgoingtobesimple.Foritspart,theNRCplannedtoworkthroughdiplomaticchannelsinJapantocomeupwithacooperativeagreementthatwaspoliticallyacceptabletoTokyo,andalsototrytoobtainbetterinformationabouttheconditionsatFukushimaDaiichiandtheradiationlevels.

Butbetterdatawouldonlyimprovethingssomewhat;equallyimportantwasa definitive plan of action from the Japanese. “[T]hey have shifted almost asfrequentlyasthewindshavechangedtherewithrespecttowhattheirprioritiesare,”Virgilioobserved.“[I]t’snotagoodsituation.”

“I’mjusttryingtofigureoutwhothepowerplayerisoverhere,”ChuckCastosaid.Fortheindustryconsortiumtosucceed,ithadtobeconsortingwiththerealdecisionmakersinJapan,andCastowasn’tsurewhothosewere.“IsTEPCOthe

right organization, or should we be going toMOD [Ministry of Defense], orwho?”

ItwasshortlyaftermidnightMarch19atWhiteFlint,andCastohadjustlefta meeting with Ambassador Roos. Roos knew he might soon face a crucialdecision:ifthesituationatFukushimaDaiichibegantodeteriorate,shouldhebereadytoorderamuchwiderevacuationofU.S.citizensandclosetheembassy?LiketheWhiteHouse,hewasdemandingbetterdataonaworst-casescenario—informationthatwouldallowhimtodecideifitwassafetostaynomatterhowbadthingsgot.TheDOEhadgivenRoostheresultsofanaccidentscenariothatCastohadnotreviewed.TheNARACmodels,usingasourcetermknownasthesupercore,wereindicatingthatdosesattheembassycouldexceedoneremoverfour days,whichwould require evacuation under theEPA’s guidelines.WhenRoos asked Casto about the numbers, Casto later told Virgilio, he felt“blindsided.” Even the American experts advising the ambassador weren’tcoordinatingtheirefforts.

In response to the previous White House request, the NRC—despite itsreservations—wasalreadydevelopingwhat it consideredaworst-casescenarioinvolvingUnits1through4.(Itwasalsoanalyzingamore“realistic”scenariotohaveonreserve.)Butnowtheambassadorapparentlywantedprojectionsforaneven more extreme scenario in which Fukushima Daiichi Units 5 and 6 alsomelteddown.ForVirgilio, thisdemandwent too far,given thatUnits5and6wererelativelystable.Healsopresumedthattheresultswouldindicatetheneedto evacuate Tokyo. “[T]hat’s why we’re trying to do a worst-case that reallymakessensegiventheconditionsthatwehavenow,”hesaid.“Imeantheteamspenthalfthenightlastnighttryingtofigureoutwheredowestartfrom.”

“Well,andIappreciate thatwork,”Castosaid.“Iexpecthe’ll turntoDOEandsay,givemetheworstcase.”

“Youknowtheoldadage,”warnedVirgilio,“‘Becarefulwhatyouaskfor.’”

“Ithinkthey’retryingtogetsomethingoutto[embassy]employeestoshowthat it’s safe . . . nomatterwhat happens—even if the extreme happens—it’ssafetobeinTokyo,”Castosaid.

Finding the right answer—or at least a best guess—for the ambassadorbecame even more urgent. The prevailing winds were about to start blowingtowardTokyoandcontinueinthatdirectionfortwelvehours.

Butthiswasnotaneasytask.ThedebateamongtheNRC,theDOE,andthe

WhiteHouseOfficeofScienceandTechnologyPolicyoverwhethertoevaluateworst-case scenarios and in fact, what exactly was the worst-case scenariocontinued to percolate over the next several days, and was a source ofconsiderable friction among the agencies. Although the NRC’s emergencyplanningstrategyincludedtheabilitytoestimatesourcetermsbasedonstylizedcases, the urgent need for the NRC to produce something that accuratelymodeledareal-worldeventputtheagencyinabind.Nobodyeverfiguredthey’dhavetodoitinrealtimeforanaccidentascomplicatedasFukushima.

At one point on March 20, the NRC’s Jim Wiggins said, in apparentfrustration,“Istillwon’tletanyoneusetheword‘worstcase’intheroomhere...becausethere’saboutfiveworstcases.”

TheWhiteHouseandtheDOEweregripingabouttheNRC’sperformanceaswell.Forinstance,theyfoundmistakesinthesourcetermsthattheNRChadbeenusing.WhentheNRCmodeledtheUnit4spentfuelpool,itassumedthatafairlylargeamountofiodine-131hadbeenreleased.Butthefuelmostrecentlydischargedintothatpoolhadagedoverthreemonths.Inthattime,mostoftheiodine-131shouldhavedecayedaway.ItturnedoutthattheNRChadreceivederroneous informationleadingthestaff tobelieve that themostrecentbatchoffuelhadbeendischargedfromthereactoronlyamonthbeforetheaccident;thus,theNRC’smodelgreatlyoverestimatedtheiodinereleaseandresultingradiationdosestothethyroidthatwouldbeassociatedwithaUnit4fire.Butbeforethismistakewas discovered,NARAChad used the source term to calculate trans-Pacific doses, finding some alarmingly high results—four rem (fortymillisievert) thyroid doses to one-year-old children in California over a two-monthperiod, for example—although thesewere still below the thresholds forprotectiveaction.

Interagency rivalries only compounded the difficulties. Early on, theNRCteamatWhiteFlintcomplainedaboutinterferencefromtheDOE’sexpertsatthenational laboratories. The DOE later fired back with its own critique. Apostaccident evaluation, prepared by two experts from Sandia NationalLaboratories, criticized the NRC, saying the agency “did not seem to engageaggressivelyuntilfourorfivedaysintotheevent.”Inaddition,NRCemergencyplanningpersonnelwere“veryreluctant”toengagewiththeirowncolleaguesonthe research staffwho had previously done analyses of events very similar tothose unfolding at Fukushima, according to the Sandia study. Other Sandiaexperts also reportedly dismissed RASCAL as a “toy model” that should nothavebeenusedtostudyreal-worldevents.

At 8:00 p.m. onMarch 19,BrianSheron led a conference call updating otherNRC staff members on the day’s events. The afternoon meeting with theindustry consortium had gone well, he reported, running beyond the ninetyminutesoriginallyplanned.IndustrypeopleseemedreceptivetoworkingcloselywithTEPCO,offeringsuggestionsorsupport.TheDOEwoulduseitsNARACresources to project dose rates in Tokyo based on the predicted wind changetowardthecity,butatthispointthereappearednoreasontoalterthefifty-mileevacuationzoneforAmericansinJapan.

Lessthananhourlater,ChuckCastowascalling.“Here’stoday’scrisis,”hesaidtoVirgilioandSheron.Afterresistingrequestsforinformationandoffersofhelpfordays,nowTEPCOwasaccusingtheUnitedStatesofdraggingitsfeet.

AmbassadorRoos,hisstaff,andCastohadjustreturnedfromameetingwiththe utility. The TEPCO officials wanted to hear the NRC’s assessment onradiation levels and the salt accumulation in the reactors—something TEPCOhad asked for just a day earlier. “Well, honestly, I didn’t have awallet inmyback pocket on that,”Casto told his colleagues. “I said, ‘Well, you askedmeabout ityesterday.There’sa lotof information,a lotofanalysis,andIbelievewe’reworkingonthat.’”TEPCOwasinsistent.“Theybasicallysaid,weneedthisstuffimmediately.”

Nowitwastimefor theNRCtostepbacka little,CastotoldVirgilio.TheDefense Department was willing to bring in whatever heavy equipment wasneeded. “[W]e’re notworking the logistics stuff,” saidCasto. “It’s out of ourlane.”AndthenewindustryconsortiumcouldworkmorecloselywithTEPCO.

As a trade-off for the NRC’s ongoing technical assistance, the Japaneseshould be expected to hand over data, Casto said. “[W]e don’t know thecondition of the reactors . . . , what containment pressure is, what reactorpressureis,whetherthosethingsareevenfull.Nevertheless,allthat’smoot.Thebottomlineisgetwater.Theyneedtogetfreshwaterintothatreactor.”2

One way to start getting freshwater for the reactors would be to getdesalinationequipmentupandrunning,butthiswouldhavetowaituntilpowerwas restored to the site. The team back at White Flint promised to reviewresearchpapersonthesaltissueandgetbacktoCastoandMonninger,whowasalsoonthelinefromTokyo.

“I’m glad you brought that up because let me make it clear,”Monningersaid. “We really need you guys to be the brain waves and giverecommendations.[H]erewecan’treallyreadstuffandcomeupwiththoughts

andrecommendationsandthatkindofstuff.Wewanttobethe,youknow,thegrease.”TheTokyogroupwas toopreoccupiedby thenever-ending streamofcrises, andperhaps just toobeat, to spendprecious time scrutinizing scientificresearch.Earlier,Monningerhadtoldhiscolleaguesheyearnedfor“100hoursofsleep.”

At10:00a.m.Sunday,March20,industryrepresentativesjoinedinaconferencecallwith theNRCoperations team atWhite Flint to brainstorm.The industryconsortium, working out of the Marriott across the street from NRCheadquarters, had agreed to send two of its technical people to Tokyo thateveningorthenextdaytoworkwithChuckCasto,andthentoembedthematTEPCO’s emergency operations center. That, everyone hoped,might improvecommunications.

Almost from the outset of the accident, the Japanese nuclear industry hadreached out to the U.S. nuclear industry for help, leaving the NRC as abystander.OnMarch12, fieldrepresentatives inJapanforGE-Hitachi,aU.S.-Japanese nuclear partnership, had contactedExelon, theChicago-based utility,and asked Exelon to run accident simulations for the reactors in its fleet thatwereofthesamedesignandvintageasthoseatFukushimaDaiichi.(However,thisinformationdidnotproveveryuseful—Exelon’sattempttomodelwhatwasgoingonatUnit1onthesimulatoratitsQuadCitiesplantpredictedaprimarycontainmentpressurethatwasonly3percentofwhatwasbeingreported.)

And the Nuclear Energy Institute appeared to have access to valuableinformationtheNRCdidn’thave.TheNEIhaddoserates thecommissionhadbeen seeking, for example. (The NRC’s information often came fromunexpectedplaces.DetailsaboutradiationlevelsinspinachcamefromtheWallStreetJournal.“It’samazinghowpeopleknowthisstuffandwecan’tseemtoget it,” marveled a member of the White Flint crew.) Maybe things wouldimprovewithindustrybridgingthegap.

ThestatusoftheUnit4spentfuelpoolstillworriedtheNRCteam.AlthoughonMarch20theJapanesehadfinallybegunusingfireenginesandthenpumpertruckstospraytonsofwatertowardtheUnit4pool,astheyhadbeendoingatUnit3 forseveraldays,workerswereshooting thewater fromsuchadistancethat“youhaveincrediblelosses,”Monningertoldhiscolleagues.(Thearrivalofthekirintruckswasstilltwodaysaway.)“[T]hemedia[arereporting]thatthesefiretrucksaregoinginandout,thehelicoptersaredoingthis,thesupercapacitypumpingsystem.Butthen,whenyouactually[get]downintoTEPCOandstart

talkingtotheengineers,youfindoutthatitreallyisn’tthateffective.”Ifithadbeen,radiationlevelswouldhavedropped,but,whenpushedonthesubject,theJapanesereportednochange.

TheNRC remained convinced the poolwas dry—a view at oddswith theJapanese belief. “We’ve got to be very careful with that because we got introublebeforebypassingupthatinformation,”warnedMonninger.

Ifthepoolwereinfactdry,thethreatitposedwasenormous.Theintenselyhot fuel could nowbemelting into the concrete pool floor.And sitting belowthatwasthetorus,filledwithmorethanamilliongallonsofwater.Ifthemoltenfuel reached the torus, it could vaporize thatwater almost instantly, causing apowerful steam explosion that could propel radioactive core material far andwide.(However,aswiththeNRC’searlierbeliefthatthepoolwasempty,fearsabout themolten fuel also provedunfounded.A computer simulation the nextdayindicatedthefuelwouldnotbehotenoughtomeltthroughthepoolfloor.)

Onanothertopic,Monningerrelatedthatafterdaysofseekinganinvitation,he and Jim Trapp had finally made it to the TEPCO emergency operationscenter. Its scale surprised them. “This place was massive,” he said. “There’sprobably 250, 300 people in that room.” In addition to the sheer size of theTEPCO operation, the visit to the utility’s operations center was notable foranother thing, Monninger told his colleagues: “There’s huge [numbers of]protesters,cameras,copssurroundingtheTEPCOfacility.”Officialvisitorswerenowwhiskedinviaanundergroundgarage.

Assuming thespent fuel in theUnit4poolwasstillcoveredwithwater, itwould require seventy-two tons more water every day to cover losses fromevaporation.TheJapanesewereaimingatleastthatmuchatit.TheUnit2poolwastargetedfortwentytonsaday;Unit3,tentonsaday;andUnit1,fivetonsaday.Butnooneknewhowmuchofthiswaterwasreachingthepoolsandhowmuchwasmissingthemandflowingelsewhereinthereactorbuildings.

“Oneof the concerns is they turn the site into a swamp,” saidMonninger,“buttheotherisjustthecontaminationandtherunofffromallthiswaterthat’snotgoingintothespentfuelpool.”

WATERREFLECTIONS

WaterpropelledbytsunamisfloodedtheFukushimaDaiichisite,disablingthepowersuppliesfornearlyallofitssafetyequipment.

Lack of water damaged the Units 1, 2, and 3 reactor cores andthreatened todamagefuel in theUnits1,2,3,and4spentfuelpools—ifthathadnotalreadyhappened.

Lackingfreshwatersources,workerstriedtoaddressthoseproblemsbyinjecting seawater into the reactor cores. But seawater corroded reactorparts more rapidly and left salt behind that might eventually block thecoolingwaterflow.

Water dumped from helicopters and sprayed from fire trucks wasintendedtorefillthepoolsandprotecttheirspentfuelfromdamage.

Butwaterthatmissedthespentfuelpoolscouldendupdrainingdowninto the reactor buildings below and flooding their basements. WorkersstrugglingtorepowertheFukushimasitemightfindtheireffortsthwartedif floodingsubmergedthesafetycomponentson theotherendsof there-runpowerlines.

Ironically,watertookawaymostoftheoptionsavailabletorespondersandleftthemnonewithoutpotentiallycatastrophicconsequences.

Thelackofinformationonthestatusofthespentfuelpoolswasjustoneofmany factors causingangst andblocking interagencyconsensusonaplausiblesource term. While the NRC had thought that it finally gave the DOE andNARACtheworst-casesourcetermtheywereseeking,NARACwascontinuingto ask the NRC for more information. At 8:30 the next morning, the WhiteHousewasconveningameetingtobringtogetherthewarringparties.Thegoalofthatmeetingwastoreachapublicpolicydecisionbasedonscience,butinthecase of source terms, the sciencewas anything but solid. Therewere just toomanyvariables,tosaynothingofbiases.

Getting thesource termrightwas farmore thananacademicexercise.Thesafety of American civilians and military personnel in Japan and potentiallymillions more in Pacific island territories, Alaska, Hawaii, and even thecontinentalUnitedStateswasinvolved.Wasthethreatrealenoughtodistributepotassium iodide tablets to reduce the effects of radiation exposure to thethyroid?Underestimating thehazardscould leavemanypeople inharm’sway.Overestimatingthemcouldresultintheunnecessarymovementoflargenumbers

ofpeople—whichitselfcouldresultincasualties.Now,itcamedowntowhetherNARACshouldusea“realistic”worstcase

ora“worst”worstcase.Butwhocouldsay,givenalltheextremeeventsthathadalreadyoccurred,whatwastruly“realistic”atthispoint?

To break the impasse, Jaczko’s office wanted the NRC to send to themeeting not only a technical expert but also someone with senior-levelcredentials and experience to go “nose to nose”withDr.StevenAoki, deputyundersecretary at the DOE, home to NARAC, to press the NRC’s position.Charlie Miller, a veteran department chief, was recruited for the task. Asuccessfuloutcome,accordingtoVirgilio,wouldbean“agreementhighenoughup thatmy folks wouldn’t continue to bang their heads against the telephoneback and forth with folks at our level about what assumptions are, and theywouldactuallydosomecalculationsforus.”

Thiswaslikelyeasiersaidthandone,however.AsMikeWeber,theNRC’sdeputyexecutivedirector, toldMiller,“probablywhatyou’regoingtofindoutaseachpartyweighsiniseverybodyhasadifferentdefinitionofworstcaseastheirown...sowe’vegottocometothecommonagreementtogoforward.”

And impatiencewith the lackofadefinitiveanswerwasgrowingamongahostoffederalagencies—allwithastakeinthedecision.AsMartyVirgilioputit, “DODwants to knowwhere tomove their ships. EPA and others want toknowwhat to expect on theWest Coast. HHS [Health and Human Services]wants to know what kind of levels in order to make recommendations onwhether or not they should actually recommend potassium iodide [tablets] atsomepoint.Anditgoessortofonandon.”

Much of the give-and-take at thatMondaymorningmeeting at theWhiteHouseremainssecret.Butat theheartof thediscussionswasfindingaway tomake thebest judgment callon radiation risks in the faceof suchuncertainty.WereconditionsdireenoughtowarrantanevacuationorderforU.S.personnelin Tokyo? Some of the data in White House hands indicated it might benecessary. At the other extreme, should the fifty-mile evacuation advisory belifted, as some were urging? (Ultimately, the fifty-mile evacuation zoneremainedinplaceuntilOctober2011,whentheStateDepartmentreducedit totwelvemiles.)

Even as Miller headed to the White House, the White Flint team wasreceiving important new information that could dramatically alter source termassumptions.TheUnit4spentfuelpool,althoughheavilydamaged,apparentlyhadwater,reducingtherisktheresomewhat.“Dowehaveanyideahowwegot

it in there?” someone asked. The answer was no; nor did anyone know howmuchwaterthepoolcontained.

TheNRCelectednottotrytochangethesourcetermnumbersatthispoint.“It took two days to negotiate this source term,” said a member of the NRCcrew. “I don’t know ifwewant to spend another twodays trying tonegotiateanotherone.”

Finally,anagreementwasreachedamongtheWhiteHousescienceadvisors,the DOE, and the NRC on a scenario the NRC pointedly referred to as “thePresident’s source term.” This case assumed releases from three reactors andfour spent fuel pools, but used “best estimate” simulations for the amount ofradioactivematerialreleasedfromeachsourcebasedoncomputermodelsoftheaccident using the NRC’s own computer code, known as MELCOR—introducingwhattheagencybelievedwas“realism”intotheanalysis.3

NARAC’sresultsforthe“President’ssourceterm”turneduponedisturbingfinding: a potential thyroid radiationdose to a one-year-old child on theWestCoastoftheUnitedStatesof4.5rem,notfarbelowthe5-remEPAthresholdforprotectiveactionssuchaspotassiumiodideadministrationorinterdictionofmilksupplies. So the fears of some Americans that Fukushima could impact themwereperhapsnotasfar-fetchedastheU.S.governmenthadledthemtobelieve.However,becausethisresultwasbelowthethreshold,itdidthetrick:evenintheworstcase,nothingneededtobedonetoprotectthechildreninCalifornia.

NARACalsodecidedtousethissourcetermtoevaluatethepotentialdosesinJapanaswell,andthatproducedanalarmingresult.“You’vegottoevacuate[Tokyo]andeverythingelse,”reportedtheNRC’sJimDyer.

ThispromptedthecrewatWhiteFlinttocomplainonceagainaboutthewaytheotheragencieswerecontinuingtoengageinthesourcetermexercise.“[W]eought to just have realistic models, not these ultraconservative worst-casethings,”saidBillBorchardt.

But even the “realistic”modelsweren’t simplifyingmatters. NARACwasalso running theNRC’s“plausible realistic” scenarios,whichassumed far lesscontainment damage than the NRC’sMELCORmodels and no releases fromanyofthespentfuelpools.Accordingtotheseresults,Japan’stwenty-kilometerevacuationzonewasnottoosmall,butratherlargerthanitneededtobe.Thencameanothersurprise:theNRCsoondiscoveredthatithadmadeyetanotherbigmistake. Its“plausible” source termwas too low,even for the“realistic”case.Although the NRC tried to cover its tracks by coming up with a post hoc

justificationfortheerror,itsbunglingofthemathdidnothelpthecommission’sstandingintheinteragencydebate.

DatawouldeventuallyshowthattheactualsourcetermwasgreaterthantheNRC’s “plausible realistic” scenarios but far less than themore extreme casesevaluated by the White House and the other agencies. Radioactive iodineconcentrationsontheWestCoastof theUnitedStatesneverreachedthelevelspredicted by theMELCOR source term. Tokyo at large was never imperiledexceptforafewhotspots,presumablycreatedbyunlikelybutunfavorablelocalweatherconditions.

However,thedoseratedatadidsupportanevacuationzoneofaboutthirtytoforty miles (fifty to sixty-seven kilometers) from Fukushima Daiichi, still amuch larger distance than the twelve-mile (twenty-kilometer) zone initiallyestablished by the Japanese government or the ten-mile emergency planningzoneinexistenceintheUnitedStatesforreactoraccidents.

For the NRC, Fukushima Daiichi redefined “realistic”—something theagencyhadstubbornlyresistedfordecades.Itsreluctancetoseriouslyconsiderthe likelihood of a severe accident with a large radiological release, even forplanningpurposes,reflectedthecommission’spropensitytoviewaccidentrisksandconsequencesthroughrose-coloredglasses.

UpuntilMarch2011,forexample,theNRCfirmlybelievedthatnorealisticaccident at aU.S. reactor couldbe seriousenough to requiremore thana ten-mileemergencyevacuation.TheNRChadadoptedthatmodestsafetystandardafter anearlier reactor emergencyprovided thenation’s first reality check: the1979accidentatThreeMileIsland.

Sincethen,theten-milezonehadremainedinviolate.IntheNRC’smind,anaccidentlikeThreeMileIsland—inwhichsomefuelmeltedbutthecontainmentheld, limiting the release of radioactivity—set the limit for theworst accidentthatneededtoberigorouslypreparedforataU.S.nuclearplant.Now,asaresultof Fukushima, the realism of this and other assumptions on safety would beseverelytested.

7

ANOTHERMARCH,ANOTHERNATION,ANOTHERMELTDOWN

The March 2011 disaster at Fukushima Daiichi recalled another early springmeltdownmore than three decades earlier. InMarch 1979, theUnit 2 reactorcore at theThreeMile Islandnuclearplant southofHarrisburg,Pennsylvania,sufferedapartialmeltdownasoperatorsstruggledoverseveraldaystoestablishcontrol.TheThreeMileIslandaccidentprovedmuchlessseriousthanthecrisisat Fukushima Daiichi, but the disasters shared much in common: designinadequacies, equipment failure, and human shortcomings. These led toinadequate cooling of the reactor cores with ensuing meltdowns, hydrogenexplosions, releases of radioactivity to the air and water, and evacuations ofmorethanonehundredthousandnearbyresidents.

There were also notable differences. Three Mile Island Unit 2 was apressurizedwaterreactor,unliketheboilingwaterreactorsatFukushima.ThreeMile Island was precipitated by an “internal event” in industry parlance, incontrast to the “external” seismic and flooding events at Fukushima. And thechallengesatFukushimaDaiichiwerefarmoreextreme,notonlybecauseofthegreaterscaleof thecrisis involvingmultiple reactorsbutbecause theoperatorshad to copewith a sustained total loss of electrical power and the inability toobtainneededsuppliesbecauseofdamagedroads.Themoreextremeconditionsledtoafarworseoutcome.

But thenegligentregulatoryandindustrialpractices thatpavedthewayforbothaccidentswerestrikinglysimilar.Thenuclearestablishmentworldwidehadthirty-twoyearstolearnfromthemistakesofThreeMileIslandandtofindwaysto avoid repeating them.Was the stage set for another disaster becauseThreeMileIsland’slessonswereforgotten?

Theshortanswersarebothnoandyes.ManyofthemistakesthatcontributedtoThreeMileIslandwereidentifiedaftertheaccidentandaddressedinaseriesof regulatory reforms, with varying degrees of effectiveness. In the UnitedStates, control room instrumentation was improved, reactor core cooling andcontainmentisolationsystemswereenhanced,operatortrainingwasintensified,andemergencypreparednessdrillswerebeefedup.Anumberof thesereformswereadoptedelsewhereintheworld.ButsomecriticalfactorsthatcontributedtotheThreeMileIslandaccidentweresweptundertherugbyregulatorsbothintheUnitedStatesandabroad.TheseunlearnedlessonsremainedunheededthreedecadeslaterwhenthewavesboredownonFukushima.Bothaccidentsfollowedfromonecommonanddangerousbelief:thatanaccidentlikeThreeMileIsland,orFukushimaDaiichi,justcouldnothappen.

TheMarch28,1979,accidentatThreeMileIslandbeganwhenapumpin thesystem providing cooling water to the Unit 2 steam generators unexpectedlystoppedrunning,forreasonsneverdetermined.Thattriggeredaseriesofeventsthatcausedthereactortoshutdownautomaticallyfromnearlyfullpower.Itwasthe thirteenth time inayear thatproblems in thiscooling systemhad forcedashutdown. In the push to restart the reactor and resume generating profitableelectricity,nobodyhadgottentotherootoftheproblem.Thistime,luckranout:a combination of equipment malfunctions, worker miscues, and design flawstransformedwarningflagsintodisaster.

Whentheaccidentbeganat4:01a.m.,Unit2wasjustthirty-sixminutesshyof its first birthday. The reactor was a Babcock &Wilcox pressurized waterdesign,capableofgeneratingaboutninehundredmegawattsofelectricity.ThreeMile Island’s owner,Metropolitan Edison Company, was a small utility withlittlenuclearoperatingexperience.

Inapressurizedwaterreactor,thecoolingwaterthatflowsthroughthecoreismaintainedatapressurehighenoughtokeepitfromboiling.Tocontrol thepressure,thereactorvesselisconnectedtoatankknownasapressurizer,whichisnormallyabouthalffilledwithwaterandhalfwithsteam.Theoperatorscanheat thecontents to increasesteampressureat thecore,or theycanaddcoolerwatertoachievethereverse.OperatorsatThreeMileIslandhadbeentaughttomake sure that the pressurizer never filled completelywithwater, a conditionknownasgoingsolid,becausethentheymightlosecontrolofthereactorvesselpressure.

Seconds after Unit 2 shut down, three standby emergency pumps

automaticallystarted torestore thecoolingwaterflowandresumetheremovalof heat through the steam generators. But a valve that had been closed formaintenancework twodaysearlier remainedclosed for reasons stillunknown,blocking the neededwater.The operators failed to notice the closed valve foreightminutes.

Absentheatremovalbythenewcoolant,thetemperatureandpressureofthewaterinsidethereactorvesselbegantoclimb.Therisingpressurecausedareliefvalveatopthepressurizertoopenanddischargewatertoacollectiontankinthecontainment building. Because the reactor had shut down, it was generatingsignificantlylessheatthanusual.That,alongwiththeopenreliefvalve,allowedthepressureinthereactorvesseltodropbelowthepointatwhichthevalvewassupposed to automatically close. But the valve stuck open, and coolingwaterkept flowing out of the vessel. Operators believed the valve had closed,however,becausetheindicatorlightonthecontrolpanelwentoff.

OnMarch28,1979,apumpprovidingcoolingwatertotheUnit2reactorattheThreeMileIslandnuclearplant south ofHarrisburg, Pennsylvania, stopped. Itwas the thirteenth timeproblems in this systemhadforcedashutdownoftheyear-oldreactor.Smallquantitiesofradiationescapedandconcernsgrewaboutahydrogenexplosion.Over thenextseveraldays tensof thousandsofPennsylvaniansfledfor theirsafety.U.S.NuclearRegulatoryCommission

Thiswasnotascenariowithoutprecedent.InSeptember1977attheDavis-Besse Nuclear Power Station near Toledo, Ohio, a sister plant to ThreeMileIsland,thereliefvalvehadstuckopenundereerilysimilarcircumstances.Therewasonenotabledifference:theOhioreactorwasoperatingthenatamuchlowerpowerlevel,givingtheoperatorsmoretimetodiagnosetheproblemandcorrect

it.Unfortunately,informationaboutthatnearmisswasnotsharedwithworkersattheeightotherreactorsofsimilardesignthenoperating,includingThreeMileIsland, or at five then under construction. The operators at Davis-Besse hadfailed to notice the stuck-open relief valve for about twentyminutes; atThreeMileIslanditwentunnoticedformorethantwohours.

Duringthisperiod,theopenvalvedischargedtensofthousandsofgallonsofcoolingwater from the reactor vessel—more than half ofwhat it held.Worsestill, theoperatorswereunawareof thisbecausetheyhadnomeansofdirectlyobservingthewaterlevelinthereactorvessel.Oddasitmayseem,therewasnosimple gauge. Instead, they relied on thewater level in the pressurizer,whichwasshowingtheamounttoberising.Somethingunexpectedwashappeningtomislead them: the stuck-open valve had reduced pressure far enough that thewater in the core could now boil and form steam bubbles. Much like whathappenswhenthecapisremovedfromabottleofsodathathasbeenshaken,theexpanding steam bubbleswere causing the volume of the coolant to increase,forcing the pressurizer level upward even though the amount of water wasdecreasing.

Anothersetofstandbyemergencypumpshadautomaticallystartedandwereprovidingmakeupwatertothereactorvessel.Thismeasurecommonlyoccurredfollowing a reactor shutdown as the rapid drop in power lowered the pressureandtemperatureofthewaterintheprimaryloop,causingitsvolumetodecreaseor“shrink.”Butthemisleadingwater-levelindicationtrickedtheoperatorsintothinking the pressurizer was in danger of overfilling and going solid. Theyturned the emergency pumps off and opened valves to drain evenmorewaterfromthereactorvessel.

Designweaknessesfurtherimpairedtheoperators’responsetotheunfoldingcalamity.Thecontrolroomcomputerdutifullyprintedoutalarmsandwarnings,but thebacklogofabnormalconditionsgrewsolargethat theprinterfellmorethan two hours behind, jamming at one point and losing critical information.Withinminutesofthestartoftheaccident,onehundredalarmsweresoundinginthe control room, adding to the operators’ stress but providing little usefulinformation.

ThedesignalsofailedtoanticipatethemagnitudeoftheeventunfoldingatThreeMile Island.Radiationdetectorshadbeen installed throughout theplant;however,manyof themwere scaled for relatively low radiation levels.As thereactorcoreexperienceddamage,thedialsonthesedetectorsmovedashighastheycouldgo,unabletoprovideanyusefuldataasradiationcontinuedtoclimb.

Detection of the rising radiationwould have helped the operators to diagnosewhatwas happening and to see if their effortswereworking. Instead, the off-scaleinstrumentsmerelytoldtheoperatorstheyhadaproblem—hardlynewsbythen.

Whilethebarrageofunreliableinformationimpairedtheoperators’abilitytorespond,aninformationvacuumhinderedresponsesoutsidetheplant.Stateandfederalofficialsknewearlyon that therewas troubleatThreeMileIsland,butlimited technology stymied their efforts to learn more. No computer linksprovidedoff-siteofficialswithreal-timedataonplantconditions. Instead, theygot strobe-light glimpses into the situation: a reactor pressure reading fromtwenty-fiveminutes ago, a core temperature value from tenminutes ago, andradiation levels from twominutes ago. Itwas like assembling a jigsawpuzzleusingpiecesfromadozendifferentpuzzles.Thedearthofreliable informationprompted NRC chairman Joseph Hendrie to remark that he and Pennsylvaniagovernor Richard Thornburgh were “like a couple of blind men staggeringaround making decisions” (prompting a strong rebuke from the NationalFederationoftheBlindforreinforcingstereotypes).

Approximately two hours after the shutdown, the water level inside thereactor vessel dropped far enough to expose portions of the nuclear fuel rods.Some of the fuel overheated and began to melt. Its zirconium alloy claddingreactedwithwatertoproducelargequantitiesofhydrogengas;someofthegasflowedthroughthestuck-openreliefvalveintothecontainmentbuilding.Moltenfuelflowedlikelavatothebottomofthereactorvessel,whereitbeganburningthroughthesix-inch-thickmetalwalls.Fortuitously,workersfinallynoticedthatthe relief valve had stuck open and closed another valve to stop the loss ofcoolingwater.

Buttheyfoundthemselvesstrugglingtoreplacethelostwaterandtorestoreforcedcoolingofthedamagedcore.Thehighpressureandthehydrogenbubblesnow occupying the reactor vessel thwarted efforts to pump more water in.Finally, after several attempts and many hours, operators were able todepressurizetheprimarysystemenoughtorestartacoolantpumpandrefillthereactorvessel.Theyweretoolatetopreventabouthalfthecorefrommeltingbutintimetostopitfromburningallthewaythroughthebottomofthevesselandspillingontothecontainmentfloor.

Aroundtenhoursaftertheaccidentbegan,therewasapressurespikeinthecontainment building—a hydrogen explosion had occurred. Fortunately, thespikewasnotstrongenoughtorupturethemassivesteel-and-concretebuilding,

whichretainedmostoftheradioactivityreleasedfromthepartiallymeltedcore.Butradioactivematerialfoundotherwaystogetout.

The operators, fooled into thinking the system had too much water, hadopened valves to drain more of it away. That water carried more and moreradioactivityasthereactorcoreoverheatedandmelted.Asitmovedtowardfourcollection tanks, the water temperature and pressure decreased as it naturallycooled down, and radioactive gases dissolved in thewater bubbled free.Ventlinesconnectedthefourtankstotwowastegasdecaytanks.Tokeepthedrainpathway open, the operators periodically discharged the contents of these twotankstotheatmosphere,andtheradioactivitytraveledalong.Inaddition,someoftheequipmentleakedradioactivityintotheauxiliarybuilding,fromwhichitlaterescapedoutside.

The venting and other flow paths reportedly released 10million curies ofradioactivityintotheair,nearlyallintheformofthenoblegasesxenon-133andkrypton-85.(TEPCOcurrentlyestimatesthatFukushimaDaiichireleasedabout13.5million curies of noble gases and about the same amount of iodine-131,along with about half a million curies of highly radioactive cesium isotopes.Comparedwith thenoblegases, radioactive iodineandcesiumaremuchmoresignificantcontributorstolong-termhealtheffects.)

Ittookaboutamonthforthereactorcoretobecomereasonablystablewithitswater temperaturebelow212°F, theboilingpoint. It tooknearly ayear forworkers to be able to enter the highly radioactive containment building toascertaintheextentofthedamage.Ittookmorethanadecade,and$973million,to clean up the accident. Japanese companies and government agenciescontributed$18millionandfortyengineers to thecleanupeffort. Inabout150minutes,abillion-dollarassetbecameabillion-dollarliability.

Well before that March day in 1979, American public opinion was deeplydivided about nuclear power, given its safety concerns and cost overruns.The1970shadseenariseinprotestsingeneral,andnuclearenergytriggereditsownrallies.AlthoughfewAmericansunderstoodthetechnology,manyknewitcouldbedangerous, and someobjected loudly to its use.Butby and large, even forthose carrying “No Nukes” signs, the risks of nuclear power remained anabstractconcept.Now,thatwouldchange.

Atabout8:00a.m.onMarch28,thetrafficreporterforradiostationWKBOin Harrisburg, Pennsylvania, heard on his car’s CB scanner that police andfirefightersweremobilizinginMiddletown,therivercommunitythatishometo

the Three Mile Island plant. WKBO’s news director telephoned Three MileIsland and was connected directly to the reactor’s control room. “I can’t talknow,we’ve got a problem,” the control roomoperator told the newsman, andreferred his caller to the plant’s owner, Metropolitan Edison Company, inReading,Pennsylvania.

There, a spokesman for Met Ed, as the company was known locally,confirmedthatageneralemergencyhadbeendeclaredbutdismisseditasa“redtape”typeofthingrequiredbytheNRCwhencertainconditionsexisted.At8:25a.m.WKBO broadcast news of problems at the plant, relying on the utility’sexplanation.

A short time later, Met Ed issued a brief press release: “At 4:00 a.m.Wednesday, the reactor atThreeMile IslandUnit 2was automatically trippedandshutdownduetoamechanicalmalfunctioninthesystem....Thereactorisbeing cooled according to designby the reactor coolant systemand shouldbecooled by the end of the day. There is no danger of [a] meltdown.” Soonafterward,teletypesclatteredinnewsroomsaroundtheUnitedStateswithashortdispatch from the Associated Press: the Pennsylvania State Police had beenadvisedofageneralemergencyattheThreeMileIslandnuclearplant.Therehadbeen “no radiation leak,” but Met Ed officials had asked for a state policehelicopterto“carryamonitoringteam.”

Infact,by8:00a.m.itwascleartoThreeMileIsland’sstationmanagerthatUnit 2 had suffered some fuel damage, based on radiation readings in thecontainmentbuilding.By9:00a.m.,NRCheadquartersinWashingtonhadbeenalerted.Fifteenminuteslater,theWhiteHousewasnotified—preciselythesamemoment that aBoston radio station reporter called themayorofHarrisburg toaskwhat thecitywasdoingabout thenuclearemergency.“Whatemergency?”askedastunnedMayorPaulDoutrich.

Flawedanddisingenuouscommunicationcontinuedashundredsofreportersfrom around the globe descended on tiny Middletown to record theunprecedented accident. From the outset, the journalists found that messagesfromtheauthoritieswerefrequentlyatoddswitheachotherorsocrypticastobe indecipherable. If nervous Pennsylvanians were looking for guidance, itwasn’tcomingfromthoseincharge—atleastinthefirstdays.“Theresponsetothe emergency was dominated by an atmosphere of almost total confusion,”concluded the President’s Commission on the Accident at ThreeMile Island,alsoknownastheKemenyCommission,initsreportsevenmonthslater.

No one seemed to know what was happening or how to respond. That

included state officials, who were charged with emergency preparedness; theNRC, which was assessing the accident from three different offices andeventually fromthescene;andMetEd,withofficials issuingstatementsat theplant site, aswell as inReading, and from theNew Jerseyhomeof its parentcompany,GeneralPublicUtilitiesCorporation.

Veryquickly,distrustcolorednearlyeveryexchange.Atan11:00a.m.newsconference the first morning, Lieutenant Governor William Scranton III toldreportersMetEdhadassuredhimthat“everythingisundercontrol.”Evenashewasspeaking,however,MetEdwasventingsteamcontainingradioactivityfromthe plant. Later that afternoon Scrantonwould tell reporters: “The situation ismorecomplexthanthecompanyfirstledustobelieve.”

For the NRC, the telephone was the prime means of communication, buttherewasnodedicated linebetweenregulatorsand thecontrol room.Thus thecommissionhadtodealinthefirstdayswithafrustratinglyincompletepicture(something thatmight have felt familiar to theWhiteFlint staffers hungry forinformation from Japanese officials three decades later). The NRC’s publicaffairsstaffwasswampedbymediacalls;staffmembersoftenhadnoupdatedinformation to provide.As forMet Ed, the utility’s public relations team hadverylittletechnicalexpertise,andtheexecutivesputforthtobriefreporterssoonlostcredibilitynotonlywiththemediabutalsowithstateandNRCofficials.1

Asthelackofreliableinformationstokedpublicfears,theNRCdispatchedto the scene Harold Denton, director of the Office of Nuclear ReactorRegulation,whobecamethepointmanforthecommission.DentonwashandedthetaskofbriefingPresidentJimmyCarter, theNRCcommissionersandstaff,andthehordesofmediawhoassembledlateeachafternoonforanewsbriefingontheaccident.

FormanyofThreeMileIsland’sneighbors—asforthefrightenedresidentslivingaroundFukushimaDaiichithirty-twoyearslater—theuppermostconcernwas the threat of a radiation release, large or small. If ThreeMile Islandwasventingradioactivity,howsafewerethey?Itwasalltooapparentthatthereasonanswerswere difficult to come bywas that the expertswere asking the samequestionsthemselves.

ByThursdaymorning,March29,theinformationtricklingoutofThreeMileIslandpromptedofficialsinHarrisburgtoraisethepossibilityofanevacuation,which would be the state’s call. Less than twenty-four hours later, GovernorThornburgh recommended that children and pregnant women living within a

five-mile radius of Three Mile Island evacuate and that schools be closed.Federalandstateexpertsweredividedon theneed for suchdrasticaction,butThornburghwasn’twillingtotakechances,fearingfurtherradiationreleases.

News of theThreeMile Island accident spread around the globe, and hundreds of reporters gathered tocover the story. Afternoonmedia briefingswere conducted by theNRC’sHaroldDenton (lower left atmicrophones), who had been dispatched to the scene to provide updates to the media, the NRC, andPresidentJimmyCarter.U.S.NuclearRegulatoryCommission

It was the first unequivocal directive delivered to a population cravingguidance.Alltold,nearly150,000people,regardlessofageorgender,piledintocarsandfled,eagertoputdistancebetweenthemselvesandthetroubledreactor.

SomehavecalledThreeMileIslandthemoststudiedaccidentinU.S.history,atleastup to that time.Twoweeksafter theaccident,PresidentCarterappointedtheKemeny Commission to investigate the accident’s causes and recommendways to prevent recurrence. TheU.S. Senate conducted its own investigation.TheNRC conducted several investigations. TheU.S. nuclear industry held itsownThreeMileIslandpostmortem.Thevariousexaminersgenerallyagreedthatthe accident largely resulted from safety studies and reviews that focused toonarrowly on nuclear plant designs and hardware and not sufficiently on thehumanpartofthesafetyequation.

Some of the most damning language came from the twelve-member

commission chaired by Dartmouth College president John G. Kemeny. TheKemenyCommission issued a blunt report inOctober 1979 after an intensivesix-monthinvestigation.

“[T]hefundamentalproblemsarepeople-relatedproblemsandnotequipmentproblems,” thecommissionwrote.“[W]hereverwelooked,wefoundproblemswiththehumanbeingswhooperatetheplant,withthemanagementthatrunsthekeyorganization,andwiththeagencythatischargedwithassuringthesafetyofnuclearpowerplants.”Thecommissionalsopointeda fingerat “the failureoforganizations to learn theproper lessons fromprevious incidents.”Asa result,“we are convinced,” the commissionwrote, “that an accident like ThreeMileIslandwaseventuallyinevitable.”

At the heart of the problem, the report said, was a pervasive attitude thatnuclear power was already so safe that there was no need to consider extraprecautions.TheKemenyCommissionurgedthat“thisattitude. . .bechangedtoonethatsaysnuclearpowerisbyitsverynaturepotentiallydangerous,and,therefore,onemustcontinuallyquestionwhetherthesafeguardsalreadyinplacearesufficienttopreventmajoraccidents.”

The nuclear industry was uncowed by these conclusions. Instead, ittrumpetedanotherfindingfromthereport:“[I]nspiteofseriousdamageto theplant, most of the radiation was contained and the actual release will have anegligibleeffectonthephysicalhealthofindividuals.”Inthedecadestofollow,nuclear power supporters would rally behind this statement and repeat theshibboleth “Nobody died at Three Mile Island.” This would become a hugestumblingblocktocomprehensivesafetyreform.

Still, themanyinvestigationsdidresult insomechippingaroundtheedges.AmongthereformsresultingfromtheThreeMileIslandaccidentwereenhancedtraining requirements for plant workers, changes in emergency responseprocedures, and improvements in control room instrumentation. Control roomoperatorsnowspendabout10percentof their timereviewingchanges toplantprocedures and refreshing their skills on full-scale simulators. Prior to ThreeMile Island, plant operators typically were required to diagnose what hadhappened and why before they could invoke the proper response procedure.After Three Mile Island, the operators were allowed to take certain steps tocounteradevelopingproblembeforeascertainingitscause.Controlpanelswerereconfigured and on/off switches were placed near relevant gauges so anoperatorcouldquicklyverifytheeffectofusingthem.

Inaddition,theNRCtooknewstepstocollectandshareinformationabout

problemsoccurringatnuclearplants.OvertheyearssinceThreeMileIsland,thecommission has issued thousands of notices to plant owners about design,maintenance,andoperatingproblemsencounteredatreactors.EarlyontheNRCwentfurther,creatingtheOfficefortheAnalysisandEvaluationofOperationalData(AEOD)toformallyreviewreportsandspotlightemergingadversetrends.(TheNRCdisbandedtheAEODinthemid-1990sasabudget-cuttingmeasure.)

Three Mile Island’s lessons also led to changes in the nuclear industry’ssafety philosophy. In the 1970s, plant owners often appliedBand-Aid fixes toequipment problems so reactors could quickly restart—even if it meant theproblemswouldsoonrecur.Butnuclearreactorsaren’tyo-yos,andcyclingthemon and off is neither wise nor cost-effective. Once companies acknowledgedthat, they paid more attention to finding and fixing problems that triggeredreactor shutdowns, such as the recurring issues at ThreeMile Island that hadprecededtheaccident.

Today,U.S.nuclearplantsoperateonaverageatabouta90percentcapacityfactor,meaning that theyarealmostalwaysproducingelectricity,exceptwhenthey are shut down for refueling, which occurs every eighteen to twenty-fourmonths.

Onedirect response toThreeMile Islandby theU.S.nuclear industrywas thecreation of the Institute of Nuclear Power Operations. Among other things,INPOfunctionsasaninformationclearinghousefor theindustry—andtosomedegreeasashadowregulator.

The déjà vu sequence of events that led to theThreeMile Island accidenteighteenmonthsafterasimilaroccurrenceatDavis-Bessewasnotunique.Inthe1970s, nuclear utilities shared little information with each other. Companieswereneedlesslyvulnerabletocommonproblemsbecauseofalackofreal-timecommunication about operating glitches and equipment malfunctions. Now,INPO requires plant owners to share good and bad practices. The goal is toenable everyone to learn from a mistake or malfunction without necessarilyhavingtoexperienceitfirsthand.

INPO also established standards of excellence and periodically evaluateseachnuclearplantagainstthosestandards.Butthesharingonlygoessofar.TheINPOassessment reportsareamong themostcloselyguardednuclear industrysecretsintheUnitedStates.NoteventheNRCgetsacopy.Thenuclearindustrydefendsthissecrecyonthegroundsthattheassessmentscanbebrutallyfrank—benefits apparently missing from publicly available (and often unjustifiably

tame)NRCassessmentreports.In1993,thepublicinterestgroupPublicCitizenobtainedconfidentialINPO

safety reports for all U.S. nuclear plants and compared them with theassessmentspreparedbytheNRCoverthesameperiod.Of463problemscitedbyINPOatfifty-sixplants,onlyaboutathirdshowedupasmattersofconcernin the NRC’s reports. INPO identified 185 specific plant problems the NRCreviewsdid not address, and in 115 cases theNRCpraised plant performancethatINPOhadredflagged.Aspokesmanforthenuclearindustryexplainedthedifferences:“TheNRC’smissionistoregulatetheindustry.INPO’smissionistobepainfullycandid...comeintoaplantandlayitbare.”

Anotherdownsideof thesecrecy—beyondhidingausefulyardstickfor theNRC’s own inspection performance—is that the public never knows to whatextentnuclearutilitiesimplementINPO’srecommendationstofixproblems.

The Three Mile Island accident also prompted the NRC to upgrade itsrequirementsforpreparingthepublicfornuclearplantemergencies.Therehadnever before been a radiation release significant enough to warrant advisingnearbyresidentstoevacuate.Now,governmentofficials—andpeoplelivingnearnuclearplants—werealertedtotheissue.

In1980, theNRCrequired thatplantownersdrawupevacuationplans forthe public within ten miles of each plant. (Compare that with the NRC’srecommendationthatU.S.citizenswithinfiftymilesofFukushimabeadvisedtoleave.)Italsomandatedthatbiennialemergencyexercisesbeconductedateachnuclear plant site. During the exercise, a plant accident is simulated and theFederal Emergency Management Agency evaluates the steps local, state, andfederalofficials take toprotect thepublic from radiation. Inparallel, theNRCevaluates howwell plantworkers respond to the simulated accident andworkwithoff-siteofficials.

The biennial exercises are better than nothing, but not by much. In thesimulation,windsareassumed toblow inonlyonedirection,convenientlybutunrealisticallylimitingthenumberofpeopleinharm’sway.Theevacuationsareonly simulated, so there is no way to tell if the complicated logistics ofevacuating all homes, businesses, schools, hospitals, and prisons could besuccessfullycarriedout. Instead, theexercisesmerelyverify thatofficialshavethe right phone numbers and contractual agreements for the buses to carryevacueesandthehospitalstotreattheinjuredandcontaminated.

These exercises only provide an illusion of adequate preparation. As theFukushima experience painfully demonstrated, rapidly moving people out of

harm’swayinthemidstofanuclearcrisisisexceedinglydifficult,yetcritical.Although thevariousThreeMile Islandreviewsconvergedon theneedfor

majornuclearsafetyupgrades,therewasnoconsensusonhowwide-rangingthereformsshouldbe.Attheheartofthesafetydebatewerethesequestions:Shouldthereformsaddressonlytheissuesraisedbythelastaccident?Orwouldthatbetantamount to fighting the last war? If the next accident were triggered by acompletelydifferenteventandproceededalongadifferenttrack,thefailureofatoo-narrowapproachwouldbeevident.BecauseoftheNRC’sregulatoryfocuson design-basis accidents that followed a certain script, it had never taken acomprehensive look at the universe of beyond-design-basis accidents—that is,everythingelsethatcouldgowrong—ortheneedtoprotectagainstthem.

The aversion to considering beyond-design-basis accidents—then called“Class9accidents”—datedbacktotheNRC’spredecessor,theAtomicEnergyCommission(AEC).OneoftheAEC’sconcernswaslaidoutbynoneotherthanHaroldDenton,thenamemberoftheAEC’slicensingstaff.DuringaJanuary5,1973,AECmeetingonreactorsitingcriteria,hestatedthat“ifClass9accidentsare considered ‘credible,’ thismaypreclude the constructionof reactors in theNortheast United States.” In other words, if protection from reactor accidentswasdeemedtorequirelargedistancesbetweenthereactorsandthepublic,theremightbenosuitablesitesinthenortheast.

However,thissentimentwasnotsharedbytheNRC’sAdvisoryCommitteeon Reactor Safeguards. The panel of experts wrote in a letter to the NRC inDecember1979:“ThelessonslearnedfromtheTMIaccidentshouldbeviewedinabroaderperspective...thereareotherpotentiallyimportantcontributorstothe probability of a reactor accident, and they should also receive priorityattention.”

Had the NRC followed that advice, the regulation and operation of thenation’sreactorscouldhavebeentransformed.Butbreakingoutofitstraditionalfocusintothisnewrealmofoversightwasnotinthecards.Instead,inthefaceofThreeMileIsland’sevidencetothecontrary,theNRCultimatelyreturnedtoitsbeliefthatbeyond-design-basisaccidentswererareenoughtolargelyignore,anditlimitedthescopeofthesubsequentregulatoryreformprimarilytofightingthelastwar.

The NRC had blown its chance to develop a comprehensive approach topreventingmeltdowns and thus had failed to learn one of themost significantlessonsfromThreeMileIsland:thatifonetypeofbeyond-design-basisaccidentcould occur, so could others. Instead, a series of ad hoc half measures and

voluntary industry “initiatives” would fill the vacuum, creating a regulatorypatchworkwithplentyofholes.TheNRCwouldrefusetorecognizethedefectsof this system fordecades, until itwas compelled to conveneyet another taskforcetoconductapostmortemonyetanothercatastrophe:Fukushima.

8

MARCH21THROUGHDECEMBER2011:“THESAFETYMEASURES...AREINADEQUATE”

OntheeveningofMarch21,ChuckCastolefttheKantei,theprimeminister’sheadquarters inTokyo, feelingupbeat.Themeetinghad finallygiven theU.S.team what it had sought for days: access to “the middle layer”—the peoplewithin the government and TEPCO who knew what was going on and werewillingtoshareinformationwiththeAmericans.

Previousmeetingswithtop-levelofficialsof theutilityandthegovernmenthadnotbeenfruitful.“Youcan’tsitandinterrogatethosepeopleandsay,givemeexactlywhat’sgoingon,becausetheydon’tknow,”Castoexplained.“Youneedthatmiddlelayerofpeople.”

Thatevening,seniorcabinetministers,utilityofficials,andtheirstaffexpertsgathered with U.S. representatives from a variety of agencies to discuss thesituation.“Oncewedidgetaccesstothemiddlelayerthenwereallygotourfeeton the ground,”Casto recalled of that evening.The first sessionwent sowellthatthegroupagreedtomeetthefollowingnight,andtheeveningconferencesbecamefixtures,continuingformonths.

TheJapaneseespeciallywantedU.S.helpindevisingasustainableinjectionsystem to deliver water to the damaged reactors. The meeting provided anopportunity to exchange informationon that andother subjects, something theAmericanswelcomed.“Itfeltgoodandsuccessful,”saidCasto.

Earlierintheday,therehadbeenadiscoverythatwasalsoonthemindsofthe Japanese. It had nothing to do with getting water into the reactors. Amonitoring survey had detected radioactive materials in the ocean about onethousandfeet(330meters)southofadischargecanalforUnits1through4.Thecanal carried heated water from the condensers to the ocean for cooling.

Normally the water flowing from the canal was not radioactive, but it nowcontainedradioactivecobalt,cesium,andiodine,atroublingsignthat theplanthadsprunganewleak.

OnMarch21,2011,radionuclides,includinglong-livedcesium,weredetectedinwateraboutonethousandfeet(330meters)southofadischargecanal(circled)atFukushimaDaiichi.Thediscoverythreatenedwhathadbeenaproductivefishingarea.ItalsoheraldedwhatwouldbecomeamountingproblemforTEPCO:whattodowithhugevolumesofcontaminatedwater.AirPhotoServiceCo.Ltd.,Japan

Someofthethousandsoftonsofwaterpumpedanddumpedintothereactorstocooltheirdamagedsystemshadpickedupradionuclidesandwasnowheadingoutintothesea.Further,thepresenceofiodine-131andtellurium-132indicatedthewaterwas leaking out of at least one core.Most of the radiation releasesearlierintheaccidenthadbeenairborneandreachedtheoceansurfaceasfalloutfromtheprevailingwinds.Thedetectionofcontaminants, including long-livedcesium,flowingdirectlyintotheseaposedaworrisomenewproblem.

Before the disaster, the waters off Fukushima Prefecture had supported athriving commercial fishing industry. The tsunami had wreaked havoc on itsfleets, ports, and processing facilities. The prospect that seafood taken fromthesewatersmightnowbecontaminatedandunsafetoeatthreatenedtodeliveranotherblowtothedevastatedregion.

Even as the struggle to gain the upper hand at Fukushima Daiichi remainedtouch-and-go,thebroaderramificationsoftheaccidentwerebecomingapparenttoofficialsinTokyo,tolocalcommunities,andtotheJapanesepublicatlarge.In response, thegovernmentcreated theNuclearSufferersLifeSupportTeam,

withadauntingmandate.Itincludednotonlysecuringhousingfortheevacuees,who eventually would number nearly 160,000, but also organizingdecontaminationefforts,supplyingevacuationcenters,securingmedicalservicesandsupplies,conductingenvironmentalmonitoring,andprovidinginformation.This,ofcourse,cameontopofeffortstohelpvictimsofthenonnucleardisaster—theearthquakeandtsunami—thathadbatteredthenortheasternregion.

For many Japanese, the accident became personal with the discovery onMarch19ofradioactiveiodine-131inrawmilkfromFukushimaPrefectureandonspinachharvested in IbarakiPrefecture,southwestof thenuclearplant.Thespinach also contained trace amounts of cesium-137. The farms where thecontamination was discovered were as far as ninety miles from the reactors:distancenolongerguaranteedsafety.Fearsthatthenation’sfoodsupplyanditsagriculturalregionsmightbethreatenedaddedanewdimensiontotheaccidentandraisedthestakesforthepublicandthegovernment.

Although the levels of contamination exceeded safety limits, governmentofficialshesitatedtoimposeaban.Theyinsteadsoughttoofferreassuranceandsuggestvoluntarymeasures.YukioEdano, thechiefcabinet secretary,assertedatapressconference thatsomeonewhoate thespinachforoneyearwouldbeexposed to the same amount of radiation as from aCAT scan—a comparisonperhapslostonthenonexpert.

Rather than issueanoutrightbanonmilk sales, theFukushimaprefecturalgovernment requested that farmers halt shipments from dairy farms withineighteen miles of the reactors. The Ibaraki government similarly asked itsfarmers to halt spinach shipments.However, it soon became apparent that thecentralgovernmenthadtoactmoreassertively.OnMarch21,itfinallybannedshipmentsofmilkfromFukushimaandvegetablesfromFukushima,Ibaraki,andtwo neighboring prefectures where these foods had been found to containradioactiveiodineandcesiumabovegovernmentlimits.

“Thelevelsarenothighenoughtohaveaneffectonhumans,soweaskthatpeopleremaincalm,”Edanotoldreporters.

Edano’s announcement,meant to reassure, had just the opposite effect fornumerousJapanese,whohadbeen told to“staycalm”overandover since thecrisisbegan.ThislatestdevelopmentdistilledtheFukushimaDaiichiaccidenttoa crucial question formany: will our food harm us?And that led to an evenlargerquestion:isourgovernmentcapableofprotectingus?

•••

“Feedandbleed” isnuclear shorthand foraprocess inwhichmakeupwater isaddedtoareactorvesselwhentheclosed-loopcoolingsystemismalfunctioning.Themakeupwaterabsorbsheatgivenoffbythenuclearfuelandisallowedtoboilaway,or“bleed,”intothecontainment.Feedandbleedcanalsobeusedtocoolspentfuelpools:inthatcase,thesteamcreatedwouldbereleasedintothereactorbuilding.

For days, the damaged reactors and spent fuel pools at FukushimaDaiichihad been kept on life support by amassive “feed and bleed” operation. If thereactorcoresandspentfuelpoolswereallintact,thelevelofradioactivityinthecoolantbleedingoffwouldhavebeenrelativelylow.Butinsteadthiswaterwashighly radioactive—a clue that it was coming into contact with fuel that hadsustainedseriousdamage.

OnMarch24, three contractors layingcable in thebasementof theUnit3turbinebuildingreceiveddosesofbetweenseventeenandeighteenrems(170to180millisieverts)whilestanding inwater.Therehadbeenwater in the turbinebuildingbasementssincethetsunami,butnooneexpectedit toberadioactive.Now it appeared that heavily contaminated water was coming in fromsomewhere.Highlevelsofiodine-131suggestedthesourcewasthereactorcore.This was very unwelcome news; it meant that the Unit 3 containment had abreach.

Twoofthemenwhocameintocontactwiththecontaminatedwatersufferedradiationburnsoftheirfeetandwerehospitalized.Thegovernmenthadalreadyupped the allowable dose rate for emergencyworkers from ten to twenty-fiveremsayearoutofconcern that theentireworkforcewouldquicklyexceed thepermitteddose.Nowthequestionbecame:wouldithavetobeincreasedagaintomaintainanadequateemergencyworkforce?

Thesituationwouldsoonworsen.OnMarch28,TEPCOdiscoveredthatanunderground trench near Unit 2 had filled with radioactive water carrying asurfacedose rateofonehundred rems (one thousandmillisieverts)perhour, alevel that could be lethal after several hours’ exposure.Radioactivewater hadbeendetectednearthedischargecanalaweekearlier,butthewaterinthetrenchhadfarhigherradioactivitylevelsandthereforeposedalargerthreat.(Therateactuallymayhavebeenhigher;onehundredremsperhourwastheupperlimitof the measuring equipment.) If the depth of the water increased by anotherthree-plusfeet(onemeter),itwouldspilloutofthetrenchandpossiblyflowintothe ocean. Japanese authorities theorized that thewater had come into contactwithmeltedfuelinsideUnit2,escapedthroughabreachinthecontainment,and

thenmadeitswaytothetrenchneartheturbinebuildings.Contaminatedwaterwasalso found in trenchesoutsidebothUnits1and3,andonApril2 inapitneartheUnit2seawaterpump,whichwassubsequentlyfoundtobeleakingintothesea.

The fact that contaminatedwaterwas getting into places it shouldn’t havebeen able to reach should have been no surprise given the stresses that thereactors’ joints, seals, and pipes had undergone during the earthquake andtsunami as well as the later explosions—stresses exacerbated by repeateddousing with many tons of water. Until electricity was restored and coolingpumpsmade operable, however, thewholesale flooding of the reactor vesselsand spent fuel pools had to continue. The fact that tons of highly radioactivewater were being generated and were finding their way into the marineenvironmentwasanunavoidableconsequence. Indeed,at thispoint,waterwastheonlycure.

TEPCO was trying to capture the tainted water, but storage space wasgrowing short. No one had ever contemplated dealing with this much water.TEPCOscrambled tofindplaces tostoreandeventually treat theexcesswaterevenasworkerscontinuedtoaddmore.

ThegrowingvolumeofradioactivewaterwouldposeaHerculeanchallenge.Theplantsitewouldeventuallybecomecrowdedwith largegraystorage tankswheretreesoncestood.Dealingwithcontaminatedwaterontheplantgrounds,aswell as controllinggroundwater flowingbeneath the site toward thePacificOcean,wouldonlygrowmoreproblematicastimewenton.

Also pressing were the challenges of removing or reducing radiationscatteredformilesacrossfarmlandandforests,inresidentialneighborhoodsandschoolyards. The magnitude and inherent difficulty of that cleanup task wereonly now becoming apparent. The fallout from Fukushima—literally andfiguratively—affected large regions. The evacuation zones now becamedecontamination zones, with varying levels of radiation, some minor, someunquestionablyhazardous,dispersedrandomly.“Hotspots”occasionallypoppedupinunexpectedplaces.Evenifitwasremovedfromtheground,contaminationcouldremainintreesandonhillsidestobecarriedeventuallybyrainshowersorbreezes tonew locations.And radioactivitydrawn inby the rootsof trees andshrubscouldbereleasedtotheatmospherelaterduringforestfires.

AfterdaysoffailedattemptstostanchtheleakintheUnit2pit—usingsawdust,garbage bags filled with shredded newspaper, and polymer—the flow finally

washaltedonApril6usingaliquid-glasscoagulatingmaterial.TEPCOreportedthatmorethan137,000gallons(520cubicmeters)ofwaterhadbeendischarged,carrying off iodine-131, cesium-134, and cesium-137. The leak convincedTEPCOthat ithadtoalter itspolicyforbiddinganydischargeofcontaminatedwastewater.Thehighlycontaminatedwaterinthetrenchesandturbinebuildingshadtobedrained,buttherejustwasnotenoughroominthetanksonsitetostoreit. The utility realized it would have to begin waste triage, discharging waterwithlowlevelsofcontaminationtomakespaceformorehazardouswater.But,TEPCO noted, any discharge would require “an adequate explanation toconvincethegeneralpublic”itwasnecessary.

The release of 11,500 tons ofwaterwas announced by the utility and thegovernmentinmediabriefingsonApril4.ButJapaneseauthoritiesneglectedtonotifyforeigngovernments,includingneighboringChinaandSouthKorea,untiltwo minutes after the discharge began, an oversight regarded by thosegovernmentsasadiplomaticgaffe.(AmongothersconcernedaboutthereleasewastheU.S.Navy,whosevesselsweredeployedoffthecoasttohelpindisasterrelief.Navyofficialsworried that the radiationmightcontaminateoceanwatertreatedforshipboarduse.)

April 6, 2011,was the opening of the school year in Japan, a daymarked byformal ceremonies. In Fukushima Prefecture, the toll of the disaster wasobvious; many school facilities awaited repairs, and playgrounds were filledwithrubbleandpilesofcontaminateddirtcoveredwithsheeting.Thenumberofincomingstudentshaddwindledinmanyareas,althoughinsomeinstancesthechildren of evacuees living in temporary shelters were hastily folded into theclassrosters.Familiarfacesofteachersoradministratorsweremissing,victimsoftheearthquakeandtsunamiorabsentbecausetheyhadlost theirhomesandbeenforcedtorelocate.

Local officials and facultyworkedhard to encourage a senseof normalcy.Families wore their best clothing; banners and flowers filled the auditoriums;educatorsgreetedstudents.Yettheongoingdisasterwasnotfarfromeveryone’sminds;normalcywasalongwayoff.

OnApril10,onedayshyofthefirst-monthanniversaryofthedisaster, theJapanese government recommended the evacuation of certain areas twelve toeighteenmiles (twenty to thirtykilometers) from theplantwhere theexpectedfirst-year dose rates would be greater than two rems (twenty millisieverts);twelve days later, it formally expanded the mandatory evacuation zone to

includesomeareasevenfartheraway,suchasIitate.Thegovernmentcouldnolonger ignore monitoring data revealing the presence of pockets of highradiation, especially to the northwest of FukushimaDaiichi. (SinceMarch 15,peoplelivinginthiszonehadbeenadvisedtostayinsidetheirhomeswithdoorsand windows sealed. Food supplies were often scarce—delivery trucks werereluctanttoenterthearea—andlivingconditionsbleak.)ThedosethresholdforevacuationwaschosenbyJapaneseauthoritiesasthelowerlimitofarangesetbytheInternationalCommissiononRadiologicalProtection,whichrecommendsthatduringemergencies,publicexposuretoradiationshouldberestrictedwithinabandoftwototenremperyear.

Thelatestadvisorysignaledtomanythat thepreviousevacuationwarningshad not gone far enough. That triggered another exodus of residents andgenerated evenmoredoubt about the reliability of informationbeingprovidedandthecompetenceofgovernmentofficials.Thesameday,abouttwothousandantinuclear protesters took to the streets in Tokyo, marching to TEPCOheadquarters and then to the headquarters of theMinistry of Economy, TradeandIndustry,whichregulatesnuclearpower.(Withinafewmonths,Fridaynightprotestsoutside theprimeminister’sofficebecamea regularevent, sometimesattracting tensof thousandsofpeople.)Acommoncomplaint among the earlymarchers:theywerenotgettingthefullstoryabouttheaccidentfromauthorities.

OntheopeningdayoftheschoolyearonApril6,2011,afirst-graderputsonherhatduringanelementaryschool enrollment ceremony in Iwaki, FukushimaPrefecture.Despite the ongoing nuclear crisis, parentsandschoolofficialsworkedtocreateasenseofnormalcyforchildren.AP

Public anger in Fukushima surged on April 19 when the governmentauthorized schools in Fukushima Prefecture to reopen provided that studentsattendingthemwouldnotreceiveannualradiationdosesofmorethantworem.Theauthoritiesmusthavethoughttheywereonsolidgroundwiththenewdoselimit.After all, the government had already decided itwas safe for everyone,including children, to live in areaswith radiation doses of up to two rem peryear.Buttheannouncementledtopuzzlementandoutrage.

Thegovernmentargued that studentswouldnot actuallybeexposed to themaximumpossible radiation levels becausemost of their timewould be spentnot in the schoolyards but inside the school buildings, where they would beshielded from radiation. Not only did the public reject that explanation, butlargerquestionsarose. If therewereschoolyards in theprefecture thatweresoheavily contaminated they might exceed the two rem per year standard, whyweren’tthesurroundingareasevacuated?

Another issue was why the government would allow children to bear thesame radiation dose as adults. In doing so, the authorities were ignoring thatchildren are particularly vulnerable to the harmful effects of radiation. Theimplications,oncetheysankin,setoffatempestofnationalprotest.

AdamningresponsecamefromToshisoKosako,arespectedresearcherwhowas servingas special advisoron radiation safety to the cabinet.OnApril 29,Kosakotearfullyresignedatanewsconferenceanddeliveredanangrystatementcriticizing the government for its “whack-a-mole” attitude in setting radiationsafetystandards.“Icannotpossiblyacceptsucha [dose] level tobeapplied tobabies, infants and primary school students, not only from my scholarlyviewpointbutalsofrommyhumanisticbeliefs,”Kosakowrote.

InlateMay,thegovernmentannounceditwouldreverttotheusualstandardof one hundredmillirems (onemillisievert) per year.And Tokyo promised tohelppayforremovalofcontaminatedtopsoilfromschoolgrounds.

Inmanycommunities,residentseagertomoveonwithlifehadalreadylaunchedcleanup campaigns of their own, not willing to wait for the government.Scrapingawayjustthreeinchesofsoilcouldreduceradiationlevelsbyasmuchas90percent,sovolunteersdressedinhazmatsuitsandpaperfacemasksusedearthmoving equipment and hand shovels to strip contamination fromplaygrounds and other public places. They handed over to their communitiesthousandsofpoundsofradioactivedirt,coveredwithplasticsheetingorstuffedintogarbagebags.

Clearly,waterwasnot theonlyby-productof theaccident thatwouldposedisposalproblems.Byoneofficialestimate,asmuchas695squaremiles(1,800squarekilometers)inFukushimaPrefecture—morethandoubletheareaofNewYorkCity—wascontaminatedwithenoughradiationtoyieldanexposureleveloffivehundredmillirems(fivemillisieverts)ormoreperyear.Andthepeopleliving on or near the contaminated soil were determined that it had to beremoved.Theywantedtogetonwiththeirlives.Astowhereitwouldultimatelygo,thatwasyettobedecided.

OnApril17,2011,TEPCOannouncedarecoveryplanthatitcalleda“roadmaptowardsrestoration.”“Bybringing thereactorsandspentfuelpools toastablecooling condition and mitigating the release of radioactive materials, we willmakeeveryefforttoenableevacueestoreturntotheirhomesandforallcitizenstobeabletosecureasoundlife,”theutilitypromised.

The roadmap set ambitious targets. The first, to be achieved within threemonths,wastoreduceon-siteradiationdoses.Thesecond, tobeaccomplishedthreetosixmonthsafterthefirsttargetwasmet,involvedbringingthereleaseofradiation “under control” and “significantly” lowering it. Immediate actionswere divided into three areas: cooling, mitigation, and monitoring anddecontamination. The ultimate goal: cold shutdown, meaning that thetemperature inside the reactors would be maintained below the boiling point,reducingthethreatofpressurebuildupandsteamreleasesandprovidingasafetymarginagainstfutureequipmentproblems.

Getting the reactors to amore stable statewas an urgent goal. FukushimaDaiichiwasstillonlyonemechanicalfailureornaturalcatastropheawayfromasecond crisis. The jury-rigged feed-and-bleed cooling systems were far fromrobust,andsafetymarginswererazorthin.

The recovery document served a dual purpose: it provided a technicalblueprintand itconveyed to thenation thatTEPCOfinallyhadagameplan—andatimetable.Perhapsnowtheendwasinsight.

FromtheperspectiveoftheNRC’sChuckCasto,thesymbolismoftheplanwas as important as its engineeringdetails. “If you’re in a shelter somewhere,youwant to see a timeline,” he said. “And from a technical point of view, itfunneledeverybody;[itsaid]thisisourpath.Itservedsomanypurposestogetthatroadmap.”

TEPCOsoughttheNRC’sinputontherecoveryplanasitwasbeingdrafted,

Casto said:“They listened touson it, [we]providedadvice.” Inhismind, theunveilingoftherecoveryplanwasawatershedmomentrankingrightbehindthemeetingwiththemidlevelgovernmentandutilitymanagersonMarch21.Now,itseemed,thingsweremovingahead.

The timetable called for the installation of closed-loop cooling systemssimilar to those existing in the reactors before the accident. (TEPCO initiallyhopedtorepairtheoriginalsystems,butfinallyacknowledgedtheyhadsufferedtoomuchdamage.)However,closed-loopsystemswouldnoteliminatetheneedtoeffectivelyandrapidlytreatthecontaminatedwateraccumulatingattheplant.

TEPCOhiredKurion,atinyCaliforniacompanythatemploysatechnologysimilartotheoneusedtotreatwastewaterfromtheThreeMileIslandaccident.Theprocessuseszeolites,microporousadsorbentminerals,tobindandfilterthecesium-137inthewater.TEPCOalsoengagedtheFrenchconglomerateArevatodevelopa secondphaseof the treatmentprocess, inwhich the residue fromtheKurionsystemwouldbemixedwithreagents,polymers,andsandtocreatearadioactive sludge-like mixture. (Some experts questioned whether the utilitywas merely trading one waste problem for another: large quantities ofradioactivewaterforlargequantitiesofradioactiveglop.)BoththeKurionandAreva systems were operating by mid-June. A third system, developed byToshiba and named SARRY, was put into operation in mid-August. Theradioactive concentrates produced by these processes were stored on-site ingrowingrowsofcontainers.

AlthoughTEPCOcalleditsplanaroadmap,itwasamapthatcarriedtheutilityand its government overseers through largely uncharted territory. The fewprecedentsthatexisted—notablythenuclearaccidentsatThreeMileIslandandChernobyl—offeredlimitedguideposts,nonesuggestingthatthefinalresolutionwouldcomequickly,simply,orcheaply.ThreeMileIslandandChernobyleachhad involved only one reactor, so a multiplier effect was immediately tackedontoprojectionsaboutFukushimaDaiichi.

ThecleanupatThreeMileIslandUnit2tookfourteenyearsandcostabout$1 billion in 1993 dollars. (Final dismantling of the damaged Pennsylvaniareactorawaitsthedecommissioningofthestill-operatingUnit1reactor,setforsometimeafter2018.)AndatThreeMileIsland,therewasnoneedforoff-sitecleanupbecauseverylittleradiationspreadbeyondtheplantproperty.

AtChernobyl, radiationcontaminatedahugearea.Although somecleanupoccurred,theSovietgovernmentexercisedanoptionunavailabletoland-starved

Japan: it simply moved people out of harm’s way. Ultimately about 350,000peoplewereresettled,andanareawithinaradiusofaboutnineteenmiles(thirtykilometers)aroundtheplantremainsan“exclusionzone.”

JustastheFukushimaaccidentwasunrivaledinitsengineeringchallenges,sotoowasitunprecedentedinitseconomicconsequences.ThatTEPCOfacedahugefinancial tollwentwithoutsaying.Twoweeksafter theaccident,TEPCOsoughta$25billionloanfromJapanesebankstohelpcoverthecostofrepairs.Bymid-April,theutilitywashuddlingwiththegovernmentinanefforttodeviseacompensationplanforvictims.Thepricetagballooned.Thegovernmentwasestimating that theaccidentwouldcost thenationaleconomyasmuchas$317billion(25trillionyen).

OnApril15,TEPCOannounceditwouldpay“temporarycompensation”of1millionyenperhousehold(about$12,700)tothoseforcedtoevacuatebecauseof the reactor accident. If the evacuees needed the money anytime soon,however, theywere due for disappointment. TEPCO required them to fill outthreeforms,oneofwhichcontainedfifty-sixpagesandwasaccompaniedbya156-page instructionbooklet.Theevacuees,manyofwhomhadbeen living incrowded shelters, were required to submit receipts for their living expenses.Theywereexpectedtoprovidemedicalrecordsandproofof lostwages.Amidpublic outcries,TEPCOeventually dispatched employees to help evacuees fillouttheforms,aprocessthatrequiredabouttwohoursperapplicant.

The growingweekly protests outside the primeminister’s office in TokyoservedasabarometerofJapan’sshiftingattitudestowarditsnuclear-dependentenergypolicy.Butitwasn’tuntilJune28,2011,thatthedepthofthatdiscontentcouldactuallybegauged.Theevent:TEPCO’sannualmeeting.Wellinadvance,there were abundant indications that this was not going to be the normal,respectfulassemblyofcontentedshareholdersinacompanythattheyearbeforehadpostedannualrevenuesofnearly$54billion.

In May, TEPCO had announced a record loss of almost $15 billion, thelargestbyanonfinancialinstitutioninJapan’shistory.(Thelossdidnotincludecompensationclaims.)PresidentShimizuannouncedheintendedtoresign.Theutility said it would sell off more than $7 billion in assets to help cover thelooming costs of compensation. On the heels of these announcements, thegovernmentmadeclearthatitwantedmorereforms.“Thisisjustthestart,”saidchiefcabinetsecretaryEdano.“Theremustbemorescrutinyandmoreeffort.”

Asantinuclearprotestersgatheredatanearbypark,about9,300shareholders—the largest crowd in TEPCO’s history—packed a hotel meeting room and

spilledoutintootherroomsandhallways.Riotpolicehelpedmaintainsecurity.During the meeting, apologies from executives were drowned by shouts andjeers. The second investor to speak called on the executives to “jump into anuclearreactoranddie.”

About 44 percent of TEPCO’s shareholders were individual investors;financial institutionsheldabout30percentof the stockandoverseas investorsabout 17 percent.Many of the individual shareholderswere elderly, includingpensioners,whohadseenthevalueoftheirstockplummet90percentsincetheaccident.

Regardless,therenominationofallsixteencurrentmembersoftheboardwasapproved. Fifteen of them were lifetime TEPCO employees; the sixteenth—aformervicegovernoroftheTokyoMetropolitanGovernment,whichwasalargeTEPCOshareholder—hadbeenontheutility’spayrollasa“crisismanagement”consultantfortwoyears.Thegruelingsix-hourmeetingendedafteramotiontoshutdownTEPCO’snuclearplantsandhaltnewconstructionwasdefeated.Themediareportedthatexitingshareholders lookedexhaustedandcomplainedthattheirviewshadnotbeenheard.

TheonlyfreshfaceintheTEPCOboardroomwasToshioNishizawa,namedto replaceShimizu as president.Hewas hardly a newcomer, however, havingspenthis career atTEPCO,most recentlyasmanagingdirector. (Nishizawa inturnwouldbe replacedelevenmonths laterafterastruggleovercontrolof thecompany.)IfTEPCO’sshareholdersweren’treadyforacorporateoverhaul,thenationalgovernmentwas.

While theNRC team in Tokyowas doing its part to help the Japanese betterunderstand what happened at Fukushima Daiichi—and how to move towardrecovery—the staff at White Flint had been handed a mandate by ChairmanGregoryJaczkoandtheotherfourNRCcommissioners.

A worriedWhite House, members of Congress, and the American publicwere pressing the NRC for answers to two fundamental questions: Can anaccidentlikeFukushimaDaiichihappenhere?Andifso,whatneedstobedonetopreventit?Theanswersrecitedsoofteninthepast—thatnuclearpowerwasinherentlysafeandthattheexistingregulationsprovidedamplepublicprotection—might not wash this time. After all, that’s exactly what the Japanese hadclaimed.

Thehastily formedNRCNear-TermTaskForce (NTTF), consistingof six

seniorexperts,began its reviewonMarch30,2011.Oneof the first andmostobviousissuesitwouldhavetotakeonwaswhetherU.S.plantswereadequatelypreparedtodealwiththekindofprolongedstationblackoutthatFukushimahadexperienced.Undertheruleinexistencesince1988,allAmericanplantshadtoshowtheycouldcopewithasimultaneouslossofoff-siteandon-siteACpowerforacertainperiod.Atthemajorityofplants,therequiredcopingtimewasjustfourhours;atoneitwassixteenhours;fortheremainder,itwaseight.

The NRC countenanced several different approaches for coping with ablackout.Onewas to rely on batteries forDC power to control plant coolingsystems that did not require AC power to function. Because these systemseventuallywouldstopworkingevenwithDCpower,theNRCrestrictedrelianceonbatteriesforcopingtonomorethanfourhours.Toprovetheycouldcopeforlonger periods, plants would have to add AC power sources beyond the twoemergencydieselgeneratorstheywerealreadyrequiredtohave.Theycoulddothisbypurchasingadditionalgeneratorsorbyconnectingtopowersuppliesfromgas turbines, hydroelectric dams, or even adjacent reactors. (The latter optionwas possible because the NRC permitted licensees to assume that a stationblackoutwouldaffectonlyone reactorata site.Consequently, licenseescouldassumethatequipmentfroma“nonaffected”reactorwouldbeavailabletoassistthe“affected”reactor.)

Each plant determined the coping time it would need based on specificfactors such as the duration of off-site power outages experienced in the past.ButtheNRCdidnotrequirethatcopingtimeanalysespostulateextremeeventsthat could cause prolonged outages. Nor did it require that coping strategiesevaluate the possibility that alternateAC sources—like those at a reactor nextdoor—might also become unavailable. And finally, it did not envision thepossibilitythatfloodingorfirecoulddisableareactor’sownelectricalsystems,sothatevenifpowersourceswereavailabletheymightnotbeusable.

The station blackout rulewas casual about thesematters in part because ablackout was considered a beyond-design-basis accident. Therefore, therequirementsaddressingitdidnotneedtobeasstringent.

The lax provisions of the station blackout rule were consistent with theNRC’slogic:morerobustprotectionsimplywasn’tneededbecausethiskindofevent was so improbable. Still, after the ten-day-long blackout at FukushimaDaiichi, these coping times appeared ridiculously low, and the agency founditselfhavingtojustifywhyimmediateactionwasn’tneededtoextendthem.

AtanNRCbriefingonstationblackoutsonApril28,CommissionerKristine

L.Svinickiaskedthestaffaquestionthatmighthavereflectedsomeofwhatsheand her colleagues were hearing, especially about the four-hour limit onbatteries.“Justtoalayperson,whentheycometoyouandsay,‘Isitreallyonlyfourhoursthatnuclearpowerplantshavetocopewithsomesortofeventofalongduration?’...ifyouweretalkingtoafamilymember,whatwouldyousaytothat?”

ThereplyofNRCstaffmemberGeorgeWilsonhadafamiliarlogic:“[H]owI’veansweredis thatwe’veonlyhadonestationblackoutintheUnitedStates.Our diesels are very reliable, and they restored that power within fifty-fiveminutes.Ialsoexplainthatwehaveredundantpowersupplies.Soyouhavetohavesomethingtotakeoutmultiplesourcesofpower.AndonceIexplainthat...usuallytheystop,orIrunoverboard.”

ItseemedtheNRC’sonlyfallbackwastosayyetagain, ineffect,“Itcan’thappenhere.”Thetaskforcehaditsworkcutoutforit.

By July 12, the NTTF turned over its first findings, a dozen multipartrecommendations for theNRC commissioners to consider—hyperspeed for anagency known for taking years to debate evenmodest rule changes, let aloneemploy them. The task force dedicated its report “to the people of Japan andespecially to those who have responded heroically to the nuclear accident atFukushima,”andexpressedits“strongdesireandourgoaltotakethenecessarysteps to assure that the result of our labors will help prevent the need for arepetitionoftheirs.”

Indirectingthetaskforce,thecommissionhadbeenmindfulofcriticismtheNRC received from the industry after theThreeMile Island accident: that theresulting recommendations were too broad and should have concerned onlyissues specific to events at Three Mile Island. (Others who had the oppositeopinion—namely, that the corrective actions ordered after Three Mile Islandweretoonarrowlyfocused—apparentlywerenotgivenmuchweight.)Thistimearound, the commission gave its task force a very specific scope of inquiry:“areasthathadanexustotheFukushimaDaiichiaccident.”

Evenso,giventhemanysimilaritiesbetweentheU.S.andJapanesenuclearoperations, that left plenty of areas ripe for scrutiny—and,many believed, foroverdueandfundamentalchanges.Highonthatlist,thetaskforcenoted,wastheneed for U.S. nuclear facilities to better prepare for station blackouts. Theblackout rule should address the possibility that amajor natural disaster coulddisruptbothon-siteandoff-siteACpowerforextendedperiods,andknockout

multiple reactors simultaneously. In other words, exactly what happened atFukushima.

ThetaskforcerecommendedrequiringU.S.plantsbeabletocoolfuelforatleast eighty hours during a station blackout without needing any assistance,equipment, ormaterials fromoff the site. For the first eight hours, the plant’spermanently installedsafetysystemsshouldbeable todo the jobwithas littleoperator action as possible. This would give the operators time to set upemergency equipment, such as diesel-powered pumps and portable generators,that could be used for the next seventy-two hours, until the off-site cavalryarrived. From that point on, the plant should be prepared to cool the fuelindefinitely without power from off-site or from the on-site primary dieselgenerators.

Thetaskforcealsoemphasizedthattheequipmentneededforthatfirsteight-hourperiodshouldbeprotectedtosomedegreefromfloodingbeyondthedesignbasis.Itproposedstoringtheequipmentfifteentotwentyfeetabovethedesign-basisfloodlevelorinwatertightenclosures.(Thetaskforcewasmoreconcernedabout flooding than about earthquakes because it believed that nuclear plantstructurescouldwithstandbeyond-design-basisearthquakesbetterthanbeyond-design-basis floods. It cited evidence that structures could survive groundshakingtwiceaspowerfulastheyweredesignedfor.Incontrast,itarguedthatfloodingwasa“cliff edge”phenomenon:aplant sitecouldbe floodedeven ifthewaterlevelonlyslightlyexceededthedesignbasis.AsCharlieMiller,headof the task force, observed, it doesn’t take a tsunami to create a crisis at areactor:“[R]egardlessofthewaythatthewatergetsinthereit’sgoingtocausethesameeffectifyourequipmentisnotprotected.”)

Thetaskforcebelievedthattheserequirementsshouldbecodifiedinanewrule.But,recognizingthatcreatingnewblackoutrulescouldtakealongtime,iturged the NRC to take interimmeasures by issuing orders to plant licensees.This could be accomplished by upgrading protection of the plants’ so-calledB.5.bequipmenttoensureitwouldescapedamageinanaturaldisaster.

AnotherissuethetaskforceflaggedwastheneedforreliablemeanstoventgasesfromMarkIandMarkIIBWRcontainmentsshould thatbeneededinastation blackout or other severe accident. Although the Fukushima Daiichireactors had been equippedwith hardened vents capable ofwithstanding highgas pressure during an accident, the vents had proven extremely difficult tooperateinanextendedblackout.NotingthatU.S.plantswouldlikelyexperiencesimilarproblemsundersimilarconditions,thetaskforcerecommendedthatthe

NRCorderplantstoupgradetheirventsystems.Most of the task force’s other recommendations were in a similar vein,

addressing specific shortcomings in protection against beyond-design-basisearthquakesandfloods,requirementsforemergencyplansandcommunications,and spent fuel pool safety. But the task force also saw a need to address thebigger picture, despite its mandate to focus only on issues with a “nexus” toFukushima.

Priority number one, according to the task force, was to clarify thecommission’s “patchwork of regulatory requirements,” developed “piece-by-piece over the decades,” for dealing with beyond-design-basis accidents. Thetaskforcepointedoutthattheserequirementsdidnotamounttoasetofcoherentguidelines.Someissuesweregivenhigherprioritythanothersbyoperatorsandregulators; as a result, somemeasures to address themweremandatorywhileothers were only voluntary. The task force recommended development of an“enhancedregulatoryframeworkintendedtoestablishacoherentandtransparentbasis for treatment of Fukushima insights.”Although the report did not say itexplicitly, the implication was that the current regulatory framework wasincoherentandopaque.

Despitethesecriticisms,thetaskforceassertedthatthe“continuedoperationand continued licensing activities [for new reactors] do not pose an imminentrisk to public health and safety.” If the task force had concluded otherwise, itwouldhavesetoffafirestorm.Still, themixedmessagesweakenedtheoverallimpactofthereportasadriverforchange.Elsewhere,however,theFukushimaaccidentpromptedsomesoul-searchingandsurprisingdeclarations.

OnMay6,PrimeMinisterNaotoKanaskedtheowneroftheHamaokanuclearplant,locatedabout125miles(twohundredkilometers)southwestofTokyo,toshutdowntworeactorsandtorefrainfromrestartingathird.Hamaokasitsatopamajorgeologicfaultandseismologistsbelievedtherewasahighlikelihoodofamagnitude 8.0 earthquake in the area in the next thirty years.Hamaoka hadlong been considered the most dangerous plant site in Japan because of itslocation. Although the plant’s owner, Chubu Electric, initially refused Kan’srequest,itagreedafewdayslater.

Thegovernment’sactionwasseenbysomeasaharbingerofthingstocome.Would the Kan government make similar requests of other plants? Wouldreactorscurrentlyshutdownforroutineinspectionsbeallowedtorestart?

Inearly July, theKangovernmentdropped theother shoe.To reassure thepublic,Japan’sreactorswouldbesubjected toa two-stagesafetycheckknownas stress tests. The first stage would be conducted at the nearly three dozenreactors currently out of service for maintenance or other safety issues todeterminetheirabilitytowithstandlargeearthquakesandtsunamis.Theresultsof that stage would be used to determine whether plants could restart. Thesecond stage would be a more comprehensive review, and its results woulddeterminewhether plants should continue to operate. (Despite their name, thestress tests were merely paper studies. No actual stressing of facilities wasinvolved.)Utilityofficialswererequiredtosubmit thefirst-stagetestresults toTokyobytheendofOctober.Onlyaftergovernmentapprovalcouldthereactorsbereturnedtoservice.Anyplansforaquickrestartduringthesummerof2011werenowonhold.

Kanwasn’tfinished.Afewdayslater,beforeanationaltelevisionaudience,hecalledonhiscountrytophaseoutitsrelianceonnuclearpower.

Inhisview, thesafetymythsurroundingnuclearpowerwasexactly that:amyth.“Japanshouldaimforasocietythatdoesnotdependonnuclearenergy,”Kan declared. “When we think of the magnitude of the risks involved withnuclearpower,thesafetymeasureswepreviouslyconceivedareinadequate.”Toalloutwardappearances,hehadbecomeanuclearapostate.

KanwasechoingsentimentstakingrootacrossJapan.Nearlythreequartersof the public supported an energy policy that would eliminate nuclear poweraltogether,accordingtoonesurvey.Inaneditorial, theJapanTimesnotedthatnuclearpower“workedforawhile,until,ofcourse,itnolongerworked.Nowisthe time tobegin thearduousprocessofmoving towards safer, renewableandefficientenergyresources.”

One newspaper described Kan’s phaseout announcement as “a completeturnaroundofthegovernment’sbasicenergyplan.”Andindeeditwas.Backin2010,thecabinethadapprovedaStrategicEnergyPlanthatcalledforbuildingfourteen new reactors by 2030, which would mean that half the nation’selectricitywould come fromnuclear power.OnlyChinawas planning amoreaggressiveconstructionprogram.

The nuclear pushwas designed to give Japan greater energy security—therationale for initially embracing the atom decades before. A larger fleet ofreactors would provide a cushion against supply or pricing problems withimported fuels, such asoil.However, nuclear powerwouldnot deliver energyindependence,becausetheJapaneseimportedalmostalloftheuraniumneeded

tofuelthenation’splants.Toprovideasecuredomesticsupplyofnuclearfuel,Japanwasintentondevelopingfastbreederreactorsandthereprocessingplantsneeded to provide them with plutonium fuel. In practice, however, thesefacilitieswereprovingtechnicallychallengingandextremelyexpensive.1

Inhisaddress,Kanconcededthatthephaseoutofnuclearpowerwouldnothappenovernight.And—aside fromendorsingmore renewable energy sources—he failed to outline how Japanmight meet its huge energy needs once thenuclearplantswereshutdown.

Kan’s motives immediately came into question. His popularity was at arecordlow,theresultofwhatwasregardedashisineffectualleadershipduringthe accident. Was this a politician’s last hurrah—an attempt to burnish atarnished legacy? Or was it the response of a leader who had experiencedfirsthandthedangersinherenttonuclearpowerandnowwantedtosteeranewcourse?Opinionsweredeeplydivided.

Kanhadpromisedtostepdownoncetheaccidentrecoverywasunderway.As a lameduck, he lacked the political capital to institute a nuclear phaseout,regardlessofhismotives,andaspokesmansubsequentlyclarifiedthatKanwasmerely announcing his personal views. Two weeks later, however, thegovernment agreed to his proposal and backed his plans for reducing Japan’srelianceonnuclearpower.

In lateAugust 2011,Kan resigned, his fifteenmonths inofficemarkedbythe worst crisis Japan had faced since the end ofWorldWar II. The task ofsteeringthenationtoanewenergypolicywouldfalltohissuccessor,YoshihikoNoda,afellowmemberoftheDemocraticPartyofJapan.InaspeechtotheDietinmid-September,Nodaoutlinedhisenergyplan.Despitepublicopposition,hepromised to restart idled reactors by the following summer, saying it was“impossible”tosustainJapan’seconomywithoutthem.Asforarapidphaseoutofnuclearpower,thatalsoappearedunlikely.“It’sstilltooearlytosayifwecangettothatstage,”NodatoldtheWallStreetJournal.

GregoryJaczkomayhavehopedthatquicklyassessingthelessonsofFukushimaanddevisinganappropriate responsewouldbea straightforward task,but thatviewapparentlywasnotsharedbyhisfellowcommissioners.Jaczkohadhintedhemightfacesomeopposition,especiallyconcerningtheninety-daydeadlinehehad set for the commission to establish its priorities. During a speech at theNationalPressClubinWashingtoninmid-July,hewasaskedwhetherhehadhis

colleagues’support forhisaggressive timetableandagenda.“Well,we’llsee,”hereplied.

Turns out he didn’t. The next day,when the fiveNRC commissioners satdownwiththetaskforcetohavetheirfirstpublicdiscussionofthereport,twoofthem promptly expressed doubt about the need for fundamental changes inregulation. Commissioner Svinicki asked whether some of the task force’srecommendations,notablythosecallingforincreasingsafetymarginsasahedgeagainstuncertainty,representeda“repudiation”oftheNRC’sincreasingrelianceon“risk-informedregulation.”

CommissionerWilliamC.Ostendorffalso tookexception to theneedforamajor overhaul. “I personally do not believe that our existing regulatoryframeworkisbroken,”hesaid.And,headded,anypolicychangesneededtobedoneinconsultationwith“ourstakeholders.”

The largest and most influential of those stakeholders, of course, is thenuclearindustry.Andthatindustryhasalwaysbelievedthatthebestdefenseisagood offense. Its leaderswere hurriedly organizing their Fukushima response,hoping to head off new rules. From the industry’s point of view, voluntaryactionsitdevisedonitsownwerepreferabletomandatoryoneshandeddownbytheNRC,and itsoonput forward itsownideas. (This tacticwasnothingnew.The NRC’s embrace of industry-proposed measures over many years wasresponsible,inpart,forthepatchworkofregulationscriticizedbythetaskforceandothers.)

The industry’s answer toFukushimawasaplan it calledFLEX, shorthandfor “diverse and flexible mitigation capacity.” FLEX envisioned a rapid-deployment force of portable equipment such as backup pumps, generators,batteries,andchargersthatwouldbeprestagedatornearnuclearfacilities.Thegoalwastoprovideredundantequipmenttokeepreactorfuelcoolforacertainperiodintheeventofaprolongedstationblackout.TheindustrypatternedFLEXafteraresponsetotheSeptember11,2001,terroristattacksandtheNRC’sB.5.borderrequiringemergencybackupequipmentintheeventofafireorexplosioncausedbyanairplanecrashingintoanuclearfacility.

AlthoughtheB.5.bequipmenthasbeentoutedasanaddedlayerofsafetyinthe event of a crisis, post-Fukushima inspections by the NRC showed that atmanysites thebackupequipmentwouldbeunlikely to functionatallduringasevere event, especially one involving a natural disaster such as a flood or anearthquake.Thisshouldnothavebeenasurprise,astheNRChadnotrequiredthat the equipment be safety-grade, or “hardened,” towithstand either design-

basisorbeyond-design-basisevents.(Inotherwords,theB.5.bequipmentcouldlegitimately have come straight off the shelf fromHomeDepot. Safety-gradecomponents, on the other hand, must meet stringent quality standards and berigorouslytestedtoconfirmproperperformance.)

Now,however, theFLEXprogramwasbeingpromotedbysomeas“B.5.bonsteroids.”Abetterdescriptionmightbe“B.5.bonfertilitydrugs.”Insteadofhardening theB.5.bequipment to safety-grade standardsorbeyond, theFLEXapproach would simply add more unhardened items. Utilities would placemultipleunitsofequipmentatdiverselocationson-oroff-siteinthehopethatnomatter what the catastrophe, something somewhere would survive to cool thereactorcoreandspentfuelpools.

Even though the FLEX approach would require the purchase of moreequipment, it would save the industry money because nuclear safety-gradestandards are costly and difficult to meet. As Charles Pardee of ExelonGenerationCompany summed it up in aDecember 2011 publicmeeting, “it’scheapertobuythree[pumps]thanoneandaheckuvabigbuilding[toputitin].”

While the NRC quibbled over how to deal with the task force’srecommendations, the summer of 2011 was producing moments that keptnuclear safety onAmericans’ radar.A flood and an earthquake—smaller thanthenaturaldisastersthathadstruckJapan—threatenedtwonuclearplants.Thesewere thekindsofevents thatnuclearoperatorsviewedassounlikely that theycouldbewrittenoff.Untiltheyhappen.

TheFortCalhounNuclearGenerationStation, north ofOmaha,Nebraska, during heavy flooding on theMissouriRiverinJune2011.Ayearearlier,theNRChadcitedtheplantanditsowner,theOmahaPublicPowerDistrict,foraninadequatefloodprotectionplan.Asaresult,newfloodbarrierswereinstalledandtheplantsurvivedthe2011floodundamaged.U.S.NuclearRegulatoryCommission

In mid-June, the Missouri River, swollen by record snowmelt and heavyspring rains, sent floodwaters surging acrossmuchof theupperMidwest.TheFort CalhounNuclear Generating Station, about thirtymiles north of Omaha,Nebraska,wentfromsittingalongsidetheMissouritosittinginit.TheNRChadissuedFortCalhounitsoperatinglicensein1973basedonrepresentationsbytheplant’s owner, Omaha Public Power District, that the plant could withstandflooding up to 1,014 feet above mean sea level. Years later, however, NRCinspectors discovered that flooding above 1,008 feet could disable vitalequipmentinseveralstructures.

The key to Fort Calhoun’s flood safety plan was old-fashioned sandbagspiled atop floodgates. NRC inspectors had previously determined that thefloodgates could not support a five-or six-foot-high stack of sandbags. Theutility’sownriskassessmentconcludedthat“severecoredamageresultsifeitherintake or auxiliary building sandbagging fails.” The possibility of floodwaterpenetratingtheplantwallswasanadditionalthreat.

Omaha Public PowerDistrict argued that the chance of a flood exceeding1,007feetabovemeansealevelwassosmallthatthesandbaggingresponsewasadequateasitstood.Nevertheless,theNRCcitedtheplantin2010,forcingtheplant to install new flood barriers. But in June 2011, the operator of anearthmover accidentally broke through a newly installed flood berm, allowingtherisingMissouritopourintotheplantsite.Waterreachedbuildingentrances.“It was a jarring sight . . . a boat tied to the nuclear plant,” said the localcongressman who toured the Fort Calhoun plant, traversing catwalks to gainaccess.Althoughwaterlevelsrosearoundtheplantentrancestoadepthoftwofeet, and operators relied on backup generators, the plant was not damagedbecauseofthenewlyupgradedfloodbarriers.

Andthencametheearthquakethatsurprisedjustabouteverybody.At1:51p.m. on August 23, 2011, a magnitude 5.8 quake rattled central Virginia, itsepicenterabout thirty-eightmilesnorthwestofRichmond.The largestpreviousearthquakeinthiszonewasreportedin1875andwasestimatedatamagnitudeof4.8.Oneofmagnitude4.5hadproducedminordamagein2003.

The North Anna Power Station sat approximately twelve miles from theepicenter.Groundmotionexceededwhattheplantwasdesignedtowithstand—

making this abeyond-design-basis accident.AlthoughNorthAnna sufferednoserious structural damage, it did temporarily lose its connection to the off-sitepower grid, just as occurred at Fukushima Daiichi. Four backup dieselgenerators automatically started and provided power for nearly four hours(althoughonesprangacoolantleakandareplacementhadtobelocated).Powerwasn’tfullyrestoredfornearlyninehours.

In both nearmisses, the plant owners and theNRCpointed to the lack ofdamageasproofthatthesafetymarginsbuiltintoU.S.reactorsandregulationswereadequate.Thatkindoflogic,criticshavelongsaid,isakintoarguingthatifa drunk driver makes it home safely, the public doesn’t need to worry aboutdrunkdriving.AtbothFortCalhounandNorthAnna,theownershadtakenextrastepsinadvancethatwouldheadoffseriousdamagefromfloodsorearthquakes.In thecaseofNorthAnna, theowner,Dominion,voluntarilyupgradedseismicprotectionatitstwounitsinthe1990swhenitlearnedthatearthquakesposedagreaterthreatthanpreviouslyknown.ThatmadeDominiontheexceptionamongnuclear utilities. Even though North Anna had survived intact, there was noassurancethatthenextplantexperiencingarudesurprisewouldbeaslucky.

AfterthequakeinVirginia,anexpertofferedatakeawaylesson.“[W]hatIwould say in terms of lessons learned from Fukushima and now yesterday’squake[atNorthAnna]isthatsettingreactordesign...hazardlimitsjustaboverecordedhumanexperienceisturningouttobereallyshortsighted,”saidAllisonMacfarlane, a geologist and environmental policy professor at GeorgeMasonUniversity.“Withsomethinglikeanuclearreactor,”shetoldareporter,“Iwouldlikealargesafetymargin.”

Macfarlane’sopinionswould sooncarryadditional clout. Inmid-2012, shewouldtakeoveraschairmanoftheNRC.Thethreatsposedbyearthquakes,shepromised,wouldmoveupontheNRC’sprioritylist.

As the NRC Near-Term Task Force moved ahead with its assessment of thelessonsfromFukushima, theagency itselfwaswrestlingwithgrowing internaldissension.EvenbeforeFukushima, Jaczkohad told friendsandacquaintancesthathefeltisolatedonthecommission,believinghimselftobethelonevoicefortougher oversight. (Commission votes were often 4–1.) But there were alsocomplaints about Jaczko’s management style. He was considered brusquetoward staff members and his fellow commissioners, and some said he waspronetointimidatingthosewhodisagreedwithhim.

As chairman, a position he assumed in 2009, Jaczko had authority over

commission activities related to budget and administrative matters. However,anynewpolicydecisionsandsafety regulations requireamajorityvote,and itwasclearasthemonthswentbythattheothercommissionersdisagreedwiththechairmanabouttheextentandtheurgencyofregulatoryreform.

Inmid-December2011,theinfightingattheNRCbecamepublicatahearingbefore the U.S. House Oversight and Government Reform Committee, whereserious allegations levied against Jaczko were aired. Two months earlier,Jaczko’s fellow commissioners—two Democrats and two Republicans—hadwrittentoWhiteHouseChiefofStaffWilliamDaleyaccusingJaczkoofcausing“seriousdamage”totheagency.Theletterexpressed“graveconcerns”abouthisleadership andmanagement style.They contended that Jaczko had improperlyinvoked emergency powers during the Fukushima accidentwithout consultinghiscolleagues,andsaidhehadsetanagendaandtimetablefortheNTTFreviewthatwentbeyondwhatthemajoritybelievednecessary.Theletteralsoclaimedthathe“intimidatedandbullied”staff.TheNRC’sinspectorgeneralinvestigatedthese allegations and ultimately exonerated Jaczko of overstepping his legalauthority,but found instances inwhichhisbehaviorwas“notsupportiveofanopenandcollaborativeworkenvironment.”

The inspector general’s findings were unflattering but hardly federaloffenses.BythetimethereportwasissuedinJune2012,however,thepoliticaldamage had been done. Jaczko had announced his resignation from thecommissionamonthearlier.AllisonMacfarlane,pledgingtoruntheNRCina“cooperativeandcollegialmanner,”wasnamedbytheObamaadministrationashisreplacement.

InJapanduring thesummerof2011, themagnitudeof the recovery taskgrewever larger, more daunting—and more costly. Although few details of theconditionsatFukushimaDaiichiweremadepublic,newswaspouringoutabouttheextentofcontaminationtothesurroundingareaandhowlongitwouldtaketogetbacktonormal.

The government was saying that up to 1,500 square miles (four thousandsquare kilometers) had been contaminated to the extent that it may requirecleanup. (Radioactive substances fromFukushimaDaiichiultimatelywouldbedetected in all of Japan’s prefectures, includingOkinawa, about one thousandmilesfromtheplant.)OnAugust26,theministerinchargeofthecrisisresponseannounced thatover thenext twoyears thegovernmentwouldcut radiation intheaffectedareabyhalf.

The goal, said the minister, Goshi Hosono, was to bring radiation levelsbelowtworems(twentymillisieverts)peryear,whichhadbeenthethresholdforevacuation but was still twenty times higher than the previous standard forpublicexposure.“[W]ithenoughgovernmentfundingandeffort,itcanbedone,”hepledged.Hosonoalsopromisedthatthegovernmentwouldbearthecostsofthecleanup,whichsomeexpertsthoughtcouldbeashighas$130billion.

Thepassageoftime—andnaturaldecayofradioactivity—woulddomostofthework;humanswouldspeednaturealongbyremovingsoil,plants,andtrees.Inareaswherechildrenmightbeexposed,thegoalwastoreduceradiationby60percent.

Forthetensofthousandsofpeoplestilllivingintemporarysheltersandforfamilies who had spent the summer with their children cooped up indoors tominimize exposure, Hosono’s announcement signaled progress. But the goodnewscamemixedwiththebad.“Someplacesmayhavetobekeptoff-limitstoresidentsforalongperiodoftimeevenaftercleanupoperationsareundertaken,”Hosonosaidatamediabriefing.ComparisonstothepermanentexclusionzonearoundChernobylwereunavoidable.

Radiation data gathered by theMinistry ofEducation andScience showedpocketsofextremelyhighreadingsacrossthecontaminatedzone.InthetownofOkuma, two miles southwest of Fukushima Daiichi, some areas recordedradiationlevelsinexcessoffiftyrems(fivehundredmillisieverts)peryear.

As much as the government—and many dispossessed residents—werepushingtorepopulatethecommunitiesnowstandingempty,itwasobviousthatnoamountofscrapingorscrubbingorisotopedecaywasgoingtomakecertainareassafe.Decontaminationeffortssimplywerenotthateffective;typicallytheycould reduce the dose rate only by about one-third. Ironically, some locationswithin the twelve-mile (twenty-kilometer)evacuationzonehad radiation levelsabovethosenowmeasuredatFukushimaDaiichi itself. Incertainplacesat theplant,radiationlevelsweredropping,thankstothemassivecleanupeffort.Thereactors,however,remainedunstableandhighlyradioactive.

Thedetailsaboutcontaminationandtheriskitcontinuedtoposespilledoutfrom government reports and media accounts as summer turned into fall. InAugust,lowlevelsofcesiumweredetectedinaricesampletakenninetymilesfrom Fukushima Daiichi. A sample of beef from Fukushima Prefecture wasfound to contain high levels of cesium. InTokyomarkets, food shoppers sawradiation levels marked alongside the prices of their favorite fruits andvegetables.And thoseeager topreyonpublic fears,especiallyamongfamilies

withyoungchildren,peddledtheirownproducts,includinga$6,500bathtubthatwastoutedasbeingabletosoakawayradiation.

It was becoming increasingly obvious that TEPCO was on the brink offinancial collapse andwould soonneed help from the Japanese government—and taxpayers.Compensationclaimsalonecouldexceed thecompany’sassets,predictedTheEconomist,whichwentontosay:“OnlythegovernmentcansaveTEPCO frombankruptcy.”The unanswered question, it said,waswhether thegovernmentwould imposewholesale reformswithin thecompany inexchangeforabailout.

TEPCO was not winning any allies among the Japanese public. In earlyOctober,theutilityannounceda15percentratehikeforcustomers.Althoughthefirst compensation checks to evacuees began arriving at about the same time,TEPCO seemed unwilling to fully acknowledge the damage it had caused. Infact, in one instance, the utility denied “owning” the radiation causing thecontamination.

The proprietors of the prestigiousSunfieldNihonmatsuGolfClub, locatedabout thirtymiles fromFukushimaDaiichi, suedTEPCO, seeking damages toclean up the closed course. The utility countered with a novel defense: theradioactivesubstancesthatfellonthecourse“belongtothelandownersandnotTEPCO.”“Weare flabbergastedatTEPCO’sargument,” saida lawyer for theclub.Theutilityalsoarguedthatradiationlevelsonthegolfcoursewerebelowallowablelevelssetforschoolyards,andthuswerenotahazard.AlowercourtagreedwithTEPCO.Onappeal,TEPCO’sdenialofownershipoftheradiationwas rejected,but theclaimforcompensationwas turneddownon thegroundsthat if the radiation levels were safe for schoolchildren, they were safe forgolfers.

OnNovember4,TEPCOgota lifeline fromthegovernment in the formofan$11.5billionbailout.Itcamewithstringsattached.Thecompanyagreedtocut7,400jobsand$31billion(2.5trillionyen)incosts.Thegovernmentasserteditwouldexpectmore,includinga“thoroughreorganization,”Edanotoldreporters.

Edano, the former chief cabinet secretary, was nowminister of Economy,Trade and Industry in the cabinet of PrimeMinisterYoshihikoNoda. (Edanostepped in as minister after the abrupt departure of the original appointee,YoshioHachiro,who,oneweekintooffice,jokedtoreportersthatcommunitiesnearFukushimaDaiichiwere“deadtowns.”Heresigned.)

WhileJapaneseofficialshadaccesstoTEPCO’sbleakfinancialpicture,thegovernmentstillremainedlargelyinthedarkaboutwhatactuallyhadhappenedatFukushimaDaiichi.On that,TEPCOwas stonewalling.Nearlyninemonthsafterthedisaster,thecompanyfinallybeganrevealingthattheaccidentwasfarworsethanithadpreviouslyacknowledged.

Clearly, Fukushima Daiichi had come close to a truly major catastrophe.Usingcomputersimulations,TEPCOestimatedthatthefuelrodsinUnit1hadcompletelymelted through the reactorvesselandeaten through6.5 feetof the8.5-foot-thickconcretefloorofthecontainmentstructure.AtUnit2,morethanhalfthefuelhadmelted,andatUnit3,almosttwo-thirdshadmelted.Thefuelinallthreewasnowsittinginthebottomsofthecontainmentstructures.Ongoingpumpingoperationswerekeepingthefuelbelow100°C(212°F),athresholdatwhich it no longer posed the threat of boiling dry.But thiswas not a reliablesystem;anotherearthquakecouldsenditcareeningoutofcontrolagain.

Afewdaysafterrevealingitsaccidentfindings, theutilityreleaseditsownassessmentofitsperformanceduringthedisaster.Thekeyconclusion:TEPCOhad made no significant errors. It was a self-serving review written byexecutives and a handpicked committee. TEPCO stressed its view that thetsunami, not the earthquake, was the direct cause of the disaster and said itsoperators had made no mistakes in dealing with the crisis. The utility alsoretracted an earlier statement that an explosion had breached the Unit 2containmentonMarch15.Thisstatementhadcontributedtoconfusionaboutthesourceofthelargereleasethatdaythatcausedradiationtospikeattheplantandcontaminated the large area to the northwest. (The report did note that manydetailswerestillunknown.)

Other examiners took amore jaundicedviewofTEPCO’s role. In comingmonths,theaccidentwouldbescrutinizedbymultipleinvestigatingcommittees,noneofwhichwouldholdTEPCOblameless.Theperiodahead for theutilitywouldberocky.

Althoughthereactorsseeminglyhadbeenpulledbackfromthebrink,therewereconstantremindersoftheprecariousconditionoftheplant.Areasofhighradiationprecludedrepairsoreveninspections,meaningthestatusofequipmentinside stayed amystery.Mountains of debris, some of it badly contaminated,remained piled up around the facility. The jury-rigged cooling systems werevulnerable to shocks ranging from another earthquake to freezing wintertemperaturesthatcouldcauserupturesofpipingexposedtotheelements.

On December 16, 2011, nine months and one week after the disaster struck,PrimeMinisterNodawentonnationaltelevisiontoannouncethatthesituationatFukushimaDaiichiwas“undercontrol.”Theplanthadachievedcoldshutdownandthereactorswerestable,hesaid.

Some experts called the assertion premature, motivated more by politicalexigencies thanengineeringcertainties. “Theplant is likeablackbox, andwedon’tknowwhatisreallyhappening,”anofficialofaneighboringtowntoldtheNew York Times. “I feel no relief.” Nor, apparently, did a huge crowd ofprotesterswhotooktothestreetsthenextdayinTokyo,bangingdrums,wavingsigns,andchanting“NoNukes.”

As 2011 came to a close, about 180 police officers and firefightersmade onefinal trip along the rugged coastline of Fukushima Prefecture, searching forbodiesofpeoplemissingfromtheearthquakeandtsunami.

Although the reactor accident itself was not directly responsible for anyimmediatedeaths,thechaosandreleasesofradioactivityofthefirstweekshadhinderedrescueefforts.Mightsomeof the tsunamivictimshavebeensaved ifrescuershadgainedaccesssooner?Itwasaquestionoftenasked,especially incommunitiesnearthereactors.

Now,asthedreadfulyearwasending,emergencyworkerslookedamongtherocksandalongthebreakwaters.Someworeprotectiveclothing,fortheirsearchtooktheminsidetheevacuationzonearoundFukushimaDaiichi.Japan’sofficialdeathtollfromthetsunamiwas15,870people,withnearly2,800missing.Morethan two hundred of the missing were from Fukushima Prefecture. No morebodieswerefound.

9

UNREASONABLEASSURANCES

On March 15, 2012, the five NRC commissioners sat in a row in a Senatehearingroom,summonedbytheEnvironmentandPublicWorksCommitteeanditsforcefulchairman,BarbaraBoxerofCalifornia.Thehearingtopic:“LessonsfromFukushima,OneYearLater.”

Despite the title, some committeemembers questionedwhether theUnitedStatesreallyhadanythingtolearnfromFukushima.Whenitwashisturntotakethemicrophone,SenatorJohnBarrassoofWyoming,therankingmemberontheEnvironment and PublicWorks nuclear safety subcommittee, decided to playdevil’s advocate. The NRC’s critics were saying, he noted, that unless theagency took stronger measures to address the vulnerabilities revealed byFukushima, then “it may be only a matter of time before a similar disasterhappens here.” Pointedly skipping over NRC chairman Gregory Jaczko,Barrassoaskedtheremainingcommissionerstorespondtotheprediction.

FirsttoreplywasCommissionerWilliamMagwood,whodeclared:“Ithinkthat our infrastructure, our regulatory approach, our practices at plants, ourequipment,ourconfiguration,ourdesignbaseswouldpreventFukushimafromoccurringundersimilarcircumstancesataU.S.plant.Ijustdon’tthinkitwouldhappen.”

Continuing down the line, commissioners Kristine Svinicki, GeorgeApostolakis,andWilliamOstendorffechoedMagwood’sassessment.

Technically, the fourcommissionerswerecorrect inasserting that“it can’thappen here”—if “it” means an event exactly like Fukushima, involving amagnitude 9.0 earthquake, a fifty-foot tsunami, four reactors in crisis, andmultiplemeltdowns and explosions. For one thing, no U.S. nuclear plant sitenow has four operating reactors. But as for a different series of calamities

triggering a core meltdown, containment breach, and widespread landcontamination?Thechanceofthathappeningislow—butitisn’tzero.

One year after the accident at Fukushima Daiichi, the five nuclear regulatory commissioners appearedbeforeaSenatecommittee,wheretheywereaskedifasimilardisastercouldhappenintheUnitedStates.Thecommissioners,fromfronttorear,wereWilliamMagwood,KristineSvinicki,NRCchairmanGregoryJaczko,GeorgeApostolakis,andWilliamOstendorff.U.S.NuclearRegulatoryCommission

Forexample,manyreactorsintheUnitedStatesaredownstreamfromlargedams.Adam failure,whether causedbyan earthquake, a terrorist attack,or aspontaneousbreach,couldrapidlyfloodoneoftheseplantswithlittlewarning,compounding any problems caused by the same event that breached the dam.Although theNRChadknown formanyyears that itwas underestimating thethreatofdambreaches,theagencywastakingitstimedecidingwhattodoaboutit.TosomeNRCstaffmembers, thecatastrophicfloodingatFukushimawasapainfulreminderofthisunresolvedvulnerabilityathome.

ITCOULDHAPPENHERE

Theterroristattacksof9/11remindedtheU.S.governmentofthethreatofcatastrophic sabotage against critical infrastructure targets. Like otherfederalagencies, theNRCbegantoreassess thevulnerabilitiesofnuclearplants.Thoseincludedmorethanterroristspilotingjetliners.Anattackonadam located upstream of nuclear facilities posed a hazard greater thanpreviouslythought.AndtheterroristthreatalertedtheNRCtothedangers

ofaccidentalfailuresofupstreamdamsaswell.Citingdomesticsecurityconcerns,theNRCconcealedformanyyears

its growingworry about the threat to reactors posed by a dam collapse.Thirty-four reactors at twenty sites around the country are downstreamfromlargedams.

A dam failure could rapidly inundate a nuclear plant and disable itsvitalpowersuppliesandcoolingsystems.Theriskofsuchfailureswasnottaken into account in the design-basis flooding analyseswhen the plantswerelicensed.Othercausesofflooding,suchasrainfall,wereconsidered,but thesepose far less riskbecause thewaterwould risemoregradually,providinggreatertimetoprepare.

Theissuebecamepublicin2012whenanNRCwhistlebloweraccusedtheagencyof coveringup informationabout thevulnerability.Oneplantappearedespeciallyatrisk:thethree-unitOconeeNuclearStationinSouthCarolina.

Thirty-four reactors at twenty sites around the United States are located downstream from largedams.Thethreatposedbythefailureofthosedamswasnottakenintoaccountwhentheplantswerelicensed.One plant especially at risk is the three-unitOconeeNuclearStation inSouthCarolina,whichsitsdownstreamofthenearbyJocasseeDam.Morethan1.4millionpeoplelivewithinfiftymilesofOconee.Google/UnionofConcernedScientists

Foryears, theNRCandOconee’sowner,DukeEnergy,havebeenatoddsaboutthemagnitudeofrisktotheplantfromafailureofthenearbyJocasseeDam.Althoughtheagencyandthecompanydisagreedabouttherisks there, they did agree on one thing: the consequences—a prolongedstation blackout leading to core melting in less than ten hours andcontainment failure in less than three days.A “significant [radioactivity]dosetothepublicwouldresult,”accordingtoDuke’sownestimates.

AlthoughtheNRChadbeenawareoftheproblemsinceatleast1996,the agency had not required safety enhancements. NRC staff membersthemselves were divided on how to proceed, and the issue was stillunresolvedwhenFukushimaDaiichi demonstrated that prolonged stationblackoutsassociatedwithfloodingweremorethanatheoreticalpossibility.

Five days after the tsunami struck the Japanese plant, an NRC staffmembere-mailedacolleaguetoinquireaboutthestatusofaJustificationfor Continued Operation (JCO) for the Oconee site, which was underdisputewithintheNRC.“InlightoftherecentdevelopmentsinJapan,”hewrote, “is anyone having second thoughts about the JCO,Oconee’s pathforward,theentireissue,etc.?AlthoughthescopeofsuchadisastermightbemorelimitedatOconeethaninJapan—thatis,theJapanesehaveotherproblemsontheirhandsthananuclearcrisis,whichisslowingthemdowntoadegree, theOconeedisasterwouldbeno less severeon the [reactor]units.Everythingonsitewouldbedestroyedoruseless.”

In reply, his colleaguewrote that thematterwasbeinghandedoff toregionalNRC officials to track as an “inspection project.” “The tsunamishould givemanagement pause as the results of it sure look likewhat Iwould expect to happen to Oconee.” Except, he noted, Oconee wouldreceivemorewater.

Plans byDuke Energy to heighten a protective floodwall at Oconee,originally scheduled for completion in 2013, are now reportedly delayeduntil2017.

Indeed, in spite of their proclamations to Senator Barrasso, the fourcommissionershadacknowledgedthatproblemsexistedafewdaysearlierwhenthey all voted to approve three major regulatory changes to addressvulnerabilities identified by the NRC’s own Fukushima NTTF. However, nolongtimeobserveroftheNRCexpectedthecommissionersattheSenatehearing

to openly profess doubts about the adequacyofU.S. reactor safety, evenwithmemoriesofFukushimaDaiichistillvivid.The“itcan’thappenhere”mind-setisdeeplyrootedattheNRC,justasitwasamongJapan’snuclearestablishmentat the time of Fukushima. In fact, some would argue, the samemind-set hascharacterizedtheNRC’sregulatoryphilosophythroughoutitshistory.

Thelegacyofthismind-setcannotbeundonewithoutstructuralreforms.Buthistoryholdsoutlittlehopethatmorefundamentalchangescanoccurwithoutaparadigm shift at the NRC. The record is replete with examples of the NRCstayingthecourseeveninthefaceofobviouswarningsigns.

A tortuous logic flourishes within the commission and influences itsdecisions.TheNRChasalwaysbeenreluctanttotakeactionsthatcouldcallintoquestion its previous judgments that nuclear plantswere adequately safe. If itwere to require new plants tomeet higher safety standards than old ones, forexample, thepublicmightno longeraccepthavingan“oldone”nextdoor.SotheNRC is constantly engaged in an elusive quest for amiddle ground fromwhich it can direct needed improvements without having to concede that theplants were not already safe enough, thereby alarming the citizenry. It is notclear,evenwiththeruinsofFukushimainfullview,thattheNRCiswillingtobreakoutofthatpattern.

Inthatregulatorybalancingact,whathasevolvedovertheyearsisadebateover“howsafeissafeenough.”Inmakingitsdeterminationsonthatissue,theNRChasalltoooftenmadechoicesthatalignedwithwhattheindustrywantedbutleftgapingholesinthesafetynet.

Theremaybenobetterexamplethanthelong-standingcontroversyovertheMark I boilingwater reactor design.Back in 1989, theNRC staffwarned thecommissionersthat“MarkIcontainmentintegritycouldbechallengedbyalargescale core melt accident, principally due to its smaller size.” Staff expertsrecommended that the NRC require Mark I reactor owners to implementmeasurestoreducetheriskofcoredamageandcontainmentfailure.

Ifthecommissionershadtakeneffectiveaction—actionthatwouldhavesentastrongmessagetoMarkIoperatorsaroundtheworld,includingthoseinJapan—itisquitepossiblethattheworstconsequencesofFukushimamighthavebeenavoided.Instead,thematterfellintoaregulatorymorassofcompetinginterestsandemergedwith a resolution that accomplished little. Itwasn’t the first timethathadhappened.

In the aftermath of the 1979 Three Mile Island accident, the KemenyCommissionmadeclearthatthesafetystatusquowasinadequate.However,thepanel explicitly refused to give its own views on “how safe is safe enough.”Without any useful external guidance, the NRC embarked on a multi-decadestruggle to provide an acceptable answer to this issue, the bane of regulatorseverywhere.Itiswithoutdoubtadifficultpublicpolicyquestion,buttheNRC’smethods of addressing it have only createdmore confusion over the decades.Fukushimamakesonethingclear:theprocesshasnotyieldedtherightanswer.

In the NRC’s world, the issue of “how safe is safe enough” is addressedthrough the concept of “adequate protection.” When Congress created theagencyoutof theashesof theAtomicEnergyCommission, theNRCinheritedthemandatebestoweduponitspredecessorbythe1954AtomicEnergyAct:to“provide adequate protection of public health and safety.” The NRC watereddown this hazy concept even further by adopting a standard of “reasonableassurance of adequate protection” in its own guidance. The standard was sovague that it essentially gave the NRC and its five political-appointeecommissioners a blank check for deciding exactly what constituted “adequateprotection.” In fact, several months after Three Mile Island, NRC chairmanJoseph Hendrie said in a speech that “adequate protection means what theCommissionsaysitmeans.”L’état,c’estmoi.

Even with such wide latitude, the NRC has always avoided specifyingprecisely what “reasonable assurance of adequate protection” means. Thisvaguenessallowsthecommissiontoavoiddrawingalineinthesand.Ina2011speech, Commissioner Ostendorff, trained as a lawyer, emphasized that“reasonable assurance does not require objective criteria, and it is alsodetermined on a case-by-case basis dependent on the specific circumstances.”Although this policy preserved a great deal of flexibility for the NRCcommissioners,thelackofaconcretestandardinjectedameasureofsubjectivityinto NRC decisions that rendered them vulnerable to political shifts over thedecades.

After the Three Mile Island fiasco, a key issue the NRC confronted waswhether it could plausibly continue to maintain that its regulations provided“reasonable assurance of adequate protection.” Certainly a lot of Americansdidn’tthinkso.ButtoadmitthatithadfailedtomeetthatstandardwouldhavethrownintoquestionthefoundationsofNRCregulations.

Uptothatpoint,regulationswerefocusedonanuclearplant’sabilitytocopewiththeseriesofhighlystylizedeventsknownas“design-basisaccidents.”On

the NRC’s list of design-basis accidents, the worst was one that assumed “asubstantial meltdown of the core with subsequent release of appreciablequantitiesoffissionproducts.”Butascatastrophicasthatseems,itwasfarfromtheworst case.Owners did not have to consider the failure ofmore than onesafetysystematatime.Theycouldassumethatemergencycorecoolingsystemswouldwork,thatpressureandtemperatureincreaseswouldbelimited,andthatcore damage would be halted before the fuel could melt through the reactorvessel. And the containment structures needed only to be strong enough toprevent leakageof radioactivematerial to theenvironmentunder thesemodestaccidentconditions.(Thisrequirementwastypicallymetthroughtheuseofsteelshellsorliners.Reinforcedconcretewasusedincontainmentbuildingstokeepthings like tornado-driven objects from getting into the reactor, not to keepmaterialwithinthereactorfromgettingout.)

Hypothetical events inwhichmultiple safety systems failed, resulting in acompletecoremeltdown, failureof the reactorvessel,andbreachorbypassofthe containment, were considered by the NRC to be “beyond-design-basis”accidents. Prior to Three Mile Island, the agency deemed such events soimprobablethat, incontrast to itspolicyfordesign-basisaccidents,“mitigationoftheirconsequences[was]notnecessaryforpublicsafety.”Atthattime,totheNRC, to achieve “adequate protection” meant to protect against design-basisaccidents.

Tocriticsof thedesign-basisapproach,ThreeMile Islanddemonstrated itsfailure; to others, however, Three Mile Island represented a validation. Theaccidentdidnotfollowthedesign-basisscriptbecausemultiplesystemfailuresoccurred (owing to faulty equipment and human error); the corewas severelydamaged;andhydrogenexplodedinthecontainment.However,thosewhosawtheglassashalffullpointedoutthattheaccidentwasterminatedbeforethecorebreachedthereactorvessel;thecontainmentneverruptured;andtheamountofradioactive material that escaped was well below what the NRC consideredacceptablefordesign-basisaccidents.

InThreeMileIsland’saftermath,oneNRC-launchedreviewoftheaccidentcametoadamningconclusionaboutthisregulatoryphilosophy:“Wehavecomefar beyond the point at which the design-basis accident review approach issufficient.”Inresponse,theNRCinOctober1980dutifullytookupthequestionof whether it needed to amend its regulations “to determine to what extentcommercial nuclear power plants should be designed to cope with reactoraccidents beyond those considered in the current ‘design basis accident’

approach.” To set that process in motion, it issued an Advance Notice ofProposedRulemaking.1

IntheAdvanceNotice,theNRCrequestedcommentonnumerousproposalsfor addressing the risk of beyond-design-basis accidents. These includedrequirements that containment structures be equippedwith systems that couldprevent them from being breached, such as filtered vents, hydrogen controlmeasures, and core catchers, structures that could safely trap molten cores iftheydidmanagetobreachreactorvessels.Anothersuggestionwastheadditionof “an alternate . . . self-contained decay heat removal system to preventdegradationofthecoreortocooladegradedcore”—inotherwords,anexternalemergencybackupcoolingsystemwith independentpowerandwatersupplies.And theNRCraised thepossibility that reactorsitingandemergencyplanningrequirementsmightneedtobetightenedtoaddressthegreaterradiationreleasesfrombeyond-design-basisaccidents.

The Advance Notice of Proposed Rulemaking sent shudders through thenuclear industry. Companies feared that the NRC was setting the stage for asweepingnewrulethatwouldrequireallplantstobeabletowithstandaccidentspreviouslyconsideredbeyonddesignbasis,compellingtheinstallationofcostlynewsystemstocopewiththem.Withoutaclearboundaryfor“howsafeissafeenough,” such a regulation could open a Pandora’s box of new requirements.Therewouldbenotellinghowfaritcouldgo.

Members of the industry quickly united under the leadership of theirU.S.tradeassociation,theAtomicIndustrialForum(apredecessortotoday’sNuclearEnergy Institute), to head off theNRCby organizing a counter-campaign: theIndustry Degraded Core Rulemaking program, or IDCOR. Funded with $15million in contributions (more than $40million in 2013 dollars) from nuclearutilitiesandvendorsintheUnitedStates,Japan,Finland,andSweden,IDCORhadasitsgoalto“assurethatarule,ifdeveloped,wouldbebasedontechnicalmeritsandwouldbeacceptabletothenuclearindustry.”

IDCOR’sextensivetechnicalprogramincludedfundingthedevelopmentofa new computer code to simulate core melt accidents and support what werecalled “realistic, rather than conservative, engineering approaches.” Yet therewas little doubt what the program hoped to accomplish: to block any newregulatoryrequirements.While theNRCvacillatedforfouryearsonwhatnewrules, ifany,wereneeded,IDCORmarchedtowarditsforegoneconclusion.Inlate1984,thegroupreleaseditsfindings.Theindustryhaddrawnitsownlinein

the sand. Risks to the public from severe accidents had been vastlyoverestimated;theactualriskswerealreadysolowthatmoreregulationwasnotneeded.

From IDCOR’s perspective, even severe nuclear accidents posed littledanger.Thatwasbecausecontainmentfailurewouldtakesolongtooccur thatmost fission products would have time to “plate out,” or stick to structureswithin the damaged reactor, and would not be released to the environment.Therefore,thequantityandtypeofradioactivematerialthatcouldescapeduringa severe accident—the source term—would be far below what the NRC hadbeenassuminginitsanalysisofhealthimpacts.Inreality,noonewoulddiefromacuteradiationexposureaftereven themostseriousaccident,and thenumbersofcancerdeathswouldbehundredsof timessmaller thanpreviousstudieshadshown.

The industry’s proposed reduction of the severe accident source termamountedtoaboldjujitsumovetoturntheNRC’soriginalefforttostrengthenregulationsonitshead.Onerequirementtheindustrywasparticularlyanxioustoundermine was the recently imposed ten-mile emergency evacuation zonearound every nuclear plant. At the time, the evacuation requirements werecausing a firestorm inNewYorkState,where state and local authoritieswereblockingoperationofthenewlyconstructedShorehamplantonLongIslandbyrefusing to certify the evacuation plan. (Critics claimed the roads of narrowLongIslandcouldn’thandleamassexodus.)Butiftheamountofradiationthatcould escape the plant was so much smaller than previously believed, thenperhapsaten-mileevacuationzonewasn’tneeded.

TheNRCmadenoattempttohideitsskepticismabouttheindustry’ssourceterm recalibrations. At a 1983 conference, Robert Bernero, director of theagency’s Office of Accident Source Term Programs, called those involved“snake oil salesmen.” To help resolve the growing controversy, the NRCcommissioned the American Physical Society, a respected professionalassociation of physicists, to conduct a review of source term research. Thephysicists concluded that, although the evidence appeared to support reducingtheassumedreleasesofcertainradionuclidesincertainaccidents, therewasnobasisforthe“sweepinggeneralization”madebyIDCOR.

Ultimately, however, the industry’s counter-campaign had an effect.Although the NRC refused to accept the industry’s arguments, in 1985 thecommissionabandonedeffortstorequireprotectionagainstsevereaccidentsandwithdrewtheAdvanceNoticeofProposedRulemaking.Infact,theNRCwenta

stepfarther,issuingaSevereAccidentPolicyStatementthatdeclaredbyfiatthat“existingplantsposenounduerisktopublichealthandsafety.”Inotherwords,there was no need to raise the safety bar to include beyond-design-basisaccidents because the NRC’s rules already provided “reasonable assurance ofadequate protection,” the vague but legally sanctioned seal of approval. TheNRChadalreadyaddressedThreeMileIslandissues,andthatwasenough.

However,inthefaceofagrowingbodyofresearchthatsuggestedthesafetypicture was not quite that rosy, this declaration raised questions more than itprovided answers. In the time-honored tradition of government bureaucracies,theNRCresolved tocontinuestudying the issue,kicking thecanfartherdownthe road and confusingmatters evenmore.While asserting that therewere nogenericbeyond-design-basisissuesatU.S.reactors,thecommissionheldoutthepossibilitythatproblemsmightexistatindividualplantsandthatitshouldtakesteps to identify them.Even thisprovedcontroversial, requiring threeyearsofgive-and-takebetweentheNRCandtheindustrymerelytosetgroundrulesforthestudy.

Whenthesmokeclearedin1988,thescopeoftheproposedIndividualPlantExamination (IPE) program had been diminished to amere request that plantowners inspect their own facilities for vulnerabilities to core melting orcontainment failure in an accident.What happened if the inspections actuallyturnedup somethingwas less clear.Even if theplant owners foundproblems,theNRCcould not automatically require them to be fixed.The agencywouldhave authority to do so only if such fixes represented “substantial safetyenhancements”andwere“cost-effective”—thatis,iftheypassedthestricttestsrequiredbytheNRC’srecentlyrevisedbackfitrule,whichgovernedthechangesitcouldrequireforexistingplants.2

The 1988 backfit rule had its origins in the antiregulatory fervor of theReagan administration. In 1981, PresidentRonaldReagan issued an executiveorderbarringfederalagenciesfromtakingregulatoryaction“unlessthepotentialbenefitstosociety...outweighthepotentialcoststosociety.”Althoughsuchacost-benefit analysis approach sounded reasonable to those seeking a way toreducegovernment interference, itwas controversial for its coldly reductionistattempt to convert the value of human lives into dollar figures that could bedirectlycomparedtothecostsincurredbyregulatedindustries.

Although theNRC, likeother independent agencies,was exempt from thisexecutive order, a majority of commissioners wanted to adopt cost-benefit

requirements anyway to add what they characterized as “discipline” to thebackfitting process (as if the NRC were staffed by some sort of renegaderegulatorymilitia.)

In the past, when the NRC had imposed new regulations, the industrycomplainedthattheresultantbackfitswerecostlyandoftenoflittleornoactualsafetybenefit.Proponentsofcost-benefitanalysisargueditwould“addressrisksthatarerealandsignificantratherthanhypotheticalorremote.”Thekeytothiswouldlieintheuseofsophisticatedmathematicalmodelingtoquantifyrisk.AtthetimeofReagan’sexecutiveorder, theNRC’sregulationsonlyallowedit toimposebackfits if theywould“providesubstantial,additionalprotectionwhichisrequiredforthepublichealthandsafetyorthecommondefenseandsecurity.”However, this standard was so vague that critics from both sides attacked it.Cost-benefitanalysisinprinciplecouldhelptosolvethatproblembyprovidingaconcrete,quantitativemethodfordeterminingwhether thebenefitsofabackfit—namely, thereduction inpotentialdeathsor injuries followinganaccident—justifiedthecosts.

RiskanalysishadareceptiveaudienceattheNRC.Formanyyears,theNRCand its predecessor, the AEC, had engaged in a similar process. In the early1970s, theAECcommissionedapioneeringproject, theReactorSafetyStudy,thatattemptedtousethetoolsofprobabilisticriskassessment(PRA)tocalculatethe risk to members of the public of dying from acute radiation exposure orcancerastheresultofanuclearreactoraccident.Riskwasdefinedastheproductofthelikelihoodofanoccurrenceanditsconsequences.Onekeyconclusionwasthatevenfornuclearaccidentswithveryseriousconsequences, the“risk”eachyeartomembersofthepublicwouldbeverylow,sincetheprobabilityofsuchaccidentswouldbeverylow.Thatis,multiplyingalargenumberbyaverysmallnumberwouldyieldasmallnumber.Thereport,issuedin1975,famouslycameunder blistering attack for its methodological problems and misleadingimplication thatanaverageAmericanhadasmuchchanceofbeingkilled inanuclearpowerplantaccidentasofbeingstruckbyameteor.

One of the main criticisms of the Reactor Safety Study was that itscalculationsofprobabilities“weresouncertainastobevirtuallymeaningless,”as recounted by Princeton professor Frank von Hippel in his book CitizenScientist.Eachcalculationrequiredtheinputofthousandsofvariables,manyofwhichhadvery largemarginsoferror. If theseuncertaintieswerenotproperlyaccountedfor,thefinalresultwouldbemisleading.Consequently,manycritics,includingan independent reviewpanelcommissionedby theNRC,argued that

probabilisticriskassessmentswerenotpreciseenoughtobeusedforcalculatingtheabsolutevalueof anything,particularly theprobability that agiven reactormightexperiencecoredamageinagivenyear.

A major source of PRA uncertainty is what types of events should beincludedinthecalculationinthefirstplace.Likegoodengineers,theearlyPRApractitioners began by analyzing things that they knew how to do—relativelywell-defined events such as a pipe break. These are called internal eventsbecause they begin with problems occurring within the plant. But addressingexternal events like earthquakes, flooding, tornadoes, or even aircraft crashesprovedmorechallenging.Firstofall,sucheventsarenotoriouslyhardtopredict.Second,theirconsequencescouldbecomplexanddifficult tomodel.Tryingtocome upwith numerical values that would accurately describe the risks fromthese eventswas an exercise in futility.But insteadof acknowledging that thefailure to address external events introduced huge uncertainties in the nuclearaccident risks they calculated, PRA analysts sometimes pretended that thepossibilities didn’t even exist—the scientific equivalent of reaching a verdictwithcrucialpiecesofevidencemissing.

Despite these technical challenges, theNRC eventually began to use PRAresultsmoreandmoreinitsregulatorydecisions—includingtheabsolutevaluesof accident risks that had been called “virtuallymeaningless.” Over time, theagency began to view PRA risk numbers as more precise than they actuallywere. They were put to heavy use in the cost-benefit analyses that somecommissionerswantedtheNRCtorelyon.Thathadatroublingconsequence:asthe risk of severe accidents appeared to shrink, so did theNRC’s leverage torequireplantimprovements.

As if calculating the PRA risk values weren’t complicated enough, cost-benefitanalysesrequiredanotherparametertobespecified:themonetaryvalueofahumanlife.TheNRChadcarriedsuchanumberonitsbookssincethemid-1970s: $1,000 per person-rem, a term used to characterize the total radiationdose toanaffectedgroupofpeople.Basedon today’sunderstandingofcancerrisk, thatput thevalueofahuman lifebetween$1and$2million. (TheNRCfailedtoadjustforinflationforyears,finallydoublingthefigureinthe1990stoabout$3millionperlife.Thatwasaboutahalftoathirdthevalueplacedonahumanlifebyotherfederalagencies.)

Althoughamajorityofcommissionersembracedthecost-benefitapproach,akeyobstacle remained: could theNRC legallyconsider costs inmaking safetydecisions?Inthemid-1980s,theUnionofConcernedScientistsandotherpublic

interest groups argued that the Atomic Energy Act did not allow cost to beconsideredatall;theNRCshouldbaseitsdecisionsstrictlyonprotectingpublichealth. If a utility could not afford to build or operate a plant to meet thatstandard,thenitwouldbeoutofluck.Inresponse,theindustryarguedthattheNRChadtherighttoconsiderthecostofbackfits.

Atfirst,theindustryprevailed.In1985,theNRCreviseditsrulestoprohibitthe commission from requiring any backfit unless it resulted in “a substantialincrease in the overall protection of public health and safety . . . and that thedirect and indirect costs of implementation . . . are justified in view of thisincreasedprotection.”Thesetestswerenotrequiredforbackfitsneededtofixan“unduerisk,”buttheNRCrefusedtodefinewhatthatmeant.

Rather than simplify matters, the backfit test made them maddeninglyunclear.Intheend,itappearedthatcost-benefitanalyseswouldberequiredforessentially all proposed backfits, including any proposals for new regulatoryrequirements. Commissioner James K. Asselstine, a lawyer who headed theSenateinvestigationintotheThreeMileIslandaccidentbeforebeingappointedto the NRC, wrote a withering dissent to the new rule. “In adopting thisbackfittingrule, theCommissioncontinues its inexorablemarchdownthepathtoward non-regulation of the nuclear industry. . . . I can think of no otherinstanceinwhicharegulatoryagencyhasbeensoeagertostymieitsownabilitytocarryoutitsresponsibilities.”

Asselstine, voting against the rule, contended that it imposedunreasonablyhighbarrierstoincreasingsafetyandrequiredadeterminationofrisk“basedonunreliable . . . analyses.”Hewasn’tdone: “TheCommissionalso fails todealwith the huge uncertainties associated with the risk of nuclear reactors. Theactual risks could be up to 100 times the value frequently picked by theCommission....Thereisnoreferenceinthisrule...tohowuncertaintiesaretobefactoredintosafetydecisions.”

In1987, theUnionofConcernedScientists, representedbyattorneysEllynWeiss and Diane Curran, sued the NRC to block the rule, arguing that thecommissioncouldnot legallyconsidercosts inmakingbackfitdecisions.Laterthatyear,anappealscourtthrewoutthebackfitrule,callingit“anexemplarofambiguityandvagueness;indeed,wesuspectthattheCommissiondesignedtheruletoachievethisveryresult.”

Butthecourt’srulingcreatedapeculiartwo-tiersystem.IndecidingUnionof Concerned Scientists v. U.S. Nuclear Regulatory Commission, the courtagreedthattheAtomicEnergyActprohibitedtheNRCfromconsideringcostsin

“setting the level of adequate protection” and required the NRC “to imposebackfits,regardlessofcost,onanyplantthatfailstomeetthislevel.”However,the ruling further confused the “howsafe is safe enough” issueby concludingthat “adequate protection . . . is not absolute protection.” The NRC couldconsider thecostsofbackfits thatwouldgobeyond“adequateprotection,” thejudgesruled.

TheNRCrevisedthebackfitruleaccordinglyin1988.Thecourt,bytyingitsdecision to the largely arbitrary “adequate protection” standard, had preservedthe agency’s free hand to push safety in any direction it wanted. The NRCrebuffed calls to provide a definition of “adequate protection.” The Union ofConcerned Scientists failed to get the revised rule thrown out on appeal.Adequateprotectionwouldremain“whattheCommissionsaysitis.”

The court’s ruling essentially froze nuclear safety requirements at 1988levels.Ifnewinformationrevealedsafetyvulnerabilitiesatoperatingplants,theNRC would have three options: conclude changes were needed to “ensure”adequate protection; redefine the meaning of “adequate protection” itself; orsubject the proposed rules to the backfit test. (The NRC also kept a fourthoption,an“administrativeexemption,”initsbackpocket.)Inanyofthesecases,mostnewsafetyproposalswouldhavetoleapahigh—perhapsimpossiblyhigh—hurdle.

The new backfit rule threw amonkeywrench into theNRC’s process foraddressing severe accident risks. Because the NRC Severe Accident PolicyStatementforthemostpartequatedadequateprotectionwithmeetingthedesignbasis, most new safety measures to deal with beyond-design-basis accidentswerenotneededforadequateprotection.Thismeantthat—unlesstheNRCweretoadmitthatoperatingplantsdidnotprovideadequateprotection,ortoexpandthe definition of adequate protection, a step that could have major legalramifications—it couldn’t issue new requirements without showing that theywere“substantial”safetyenhancementsandthattheymetthecost-benefittest.

Whenconcernstartedtogrowaboutthestrengthofthecontainmentofonetypeof reactor in particular, theMark I boilingwater reactor, theNRC founditself inastraitjacket. If theagencywere torequiresafetyfixesfor theMarkIcontainmentonthebasisof“ensuring”or“redefining”adequateprotection,thiswouldbeseenasanadmissionthatthefleetofMarkIswasunsafe.Otherwise,theNRCwouldhavetoprovethebenefitsjustifiedthecosts.Thatoptionwouldleavethefateofanysafetyimprovementsatthemercyoftheriskassessors.

In the 1980s, therewere twenty-fourGEMark I boilingwater reactors in theUnitedStates.Becauseoftheirrelativelysmallandweak“pressuresuppression”containment structures, these reactors had been controversial almost from thetimethatthefirstcommercialversion,OysterCreekinNewJersey,wentonlinein1969.After thehydrogenexplosionatThreeMile Island, in1981 theNRCrequired that the relativelyvulnerableMark Iand IIcontainmentsbe“inerted”withnitrogengastopreventsuchexplosions.

ButthatwasnottheMarkI’sonlyproblem.AsNRCstaffmembersbegantocontemplate events they had never thought possible beforeThreeMile Island,additional frightening scenarios began to emerge. For instance, if a prolongedstationblackoutweretooccur,operatorswouldlosetheabilitynotonlytocoolthecorebutalsotoremoveheatfromthecontainment,whichcouldeventuallyover-pressurize and leak through seals not designed to withstand such highpressures and temperatures. Evenworse, if powerwere not restored, the corewouldmeltthroughboththereactorvesselandthesteelcontainmentliner.Sucheventswouldinexorablyresultinbreachesofeachofthemultiplelayersmeanttopreventradioactivematerialsfromreachingtheenvironment.

The NRC was already addressing station blackout issues under a 1988regulation. But that only required plants to develop a strategy to copewith ablackoutfornomorethansixteenhours.AprolongedstationblackoutataMarkIreactor—onelongerthanthe1988rulecontemplated—woulddefeattheNRC’s“defense-in-depth”multiple-barrier strategy forprotecting thepublic.AnNRCtaskforceconvenedin1988tostudythelinermelt-throughissueconcludedthatthisvulnerabilitywasa“riskoutlier”thatwarrantedpromptattention.

Thatwaseasiersaidthandone,becausetheindustry’sIDCORprogramwasalready out front with its opposite argument. At the same time the NRC’sanalyseswereraisingalarmsaboutlinermelt-through,IDCORwasassertingthattherisksofcoredamageandcontainmentbreachwereverylow.Inaddition,anindustry group, the Nuclear Utility Management & Resources Council (nowfolded into the Nuclear Energy Institute), immediately submitted a reportopposing the NRC task force’s conclusions, asserting that generic hardwaremodificationstotheMarkIwerenotcost-beneficialbecause“thetotalriskfromseverecoremeltaccidentsislow.”InplaceofmandatoryfixestotheMarkI,theindustrywantedtheNRCtoconsiderplantsonacase-by-casebasisaspartoftheongoing Individual PlantExamination program,whichwould takemanymoreyearstocomplete.

Forthenextseveralyears,theNRCstaffandtheindustrycontinuedtowield

dueling technical analyses to get the upper hand with the commissioners. Tocomplicate matters, the NRC staff itself was divided, with some membersaligningwiththeindustry.ThetradejournalInsideN.R.C.,coveringathree-daymeetingin1988inwhichquarrellingNRCstaffandofficialsweresequesteredinaBaltimorehotel,quotedsourcesasstatingthat“thereisliterallyawargoingon”andalludingtoinstancesinwhich“disagreementovertheMarkIissueledto threats involving jobsecurityand research funding.”Onesource told InsideN.R.C.that“therearesomeseniorstaffmemberswhoaredoingeverythingtheycantomakesurethegameisplayedbyindustry’srules. . .iftheindustrycanwinthisone,theycanwineverything.”

AtthecoreofthedisputewasthequestionofhowmuchrisktheMarkIfleetposed (an issue that would again loom large in 2011). Although the NRC’sanalysesshowedahighlikelihoodthataMarkIreactor’scontainmentwouldfailif the corewere damaged, even the agency’s staff believed that the chance ofcore damagewas low—perhaps lower than at a pressurizedwater reactor likeThreeMileIsland.SotheoverallrisktothepublicmightnotbeanygreaterfromtheMarkIthanfromotherreactortypes.

Ifso,itwouldbehardtodemonstratethatfixingtheMarkIproblemswouldreduce risks by a big enough factor to satisfy the requirements of the backfitrule. And the majority of commissioners would not be likely to perturb thecherished meaning of “adequate protection” to address the problem via thatroute.Afewweeksafter thecontentiousBaltimoremeeting,ThemisSpeis, thedirectoroftheNRC’sresearchoffice,wroteaninternalmemoranduminwhichhecontendedthatimprovementstoreducethelikelihoodofcontainmentfailurewouldprobablybeblockedbythebackfitrule.

Notwithstanding a likely defeat, the NRC staff went before thecommissionersinearly1989withaproposalforfivecriticalimprovementsforMarkIplantsthatreducetheirriskofcoredamageandcontainmentfailure.Thestaffaskedthecommissionersto:

• Speedupimplementationofthe1988blackoutrule.• Requireacquisitionofbackupwatersuppliesandpumps thatcouldoperateinastationblackout.

• Require hardened torus vents that could be used during accidents to expelsteam and other gases to reduce containment pressure and temperature.Crucially, operators should be able to open and close the vent valvesremotelyandintheabsenceofACpower.

• Require that the systems needed to automatically depressurize the reactorvessel in an accident—an essential step to be able to pump emergencycoolant into anoverheating core—bemademore reliable, especially in thecase of an extended station blackout when the battery power needed tooperatethevalveswouldnotbeavailable.

• Requiremore robust emergency procedures to ensure that operators couldeffectivelyutilizeallthisnewhardware.

The staff argued that certainMark I containment failuremodes, such as linermelt-through, could not be stopped should a core meltdown occur. The onlystrategywas to preventmeltdowns in the first place—and for that the backupcoolant supplies and hardened containment vents were crucial. The staffpresentedcalculationssupportingitsclaimthattheimprovementswouldpassthebackfit test. The staff’s analysis showed that the owners of theMark I couldreduce the likelihoodofcoredamagebya factorof tenby installinghardenedvents:asubstantialsafetyincrease.Thestaff’scalculationsalsoshowedthecostoftheimprovementsjustifiedthebenefits.

At the commission meeting, the NRC staff faced a hostile audience inCommissionerThomasRobertsandhiscolleagues.TheywerenothelpedbythefactthattheAdvisoryCommitteeonReactorSafeguards,theindependentpanelthatreviewsNRCactivities,alsovigorouslyopposedthestaffandsupportedtheindustry.

Despite the commissioners’ skepticism at the briefing, they remaineddeadlockedformonthsontheMarkIimprovementproposal.ThetiebreakerwasCommissioner James Curtiss. The NRC staff told Curtiss that if thecommissioners did not vote for the containment improvement program, andinstead folded it into the Individual Plant Examination program,Mark I fixeswouldbeputoffforanotherfiveyears.Curtissapparentlybelievedresolvingtheissuecouldnotwaitthatlong.

In July1989, the commission finallymade itsdecision.Although the finalvotewas3–2 in favorof takingaction, theoutcomewas far shortofwhat thestaffhadrequested.Ofthefiverecommendations,thecommissionacceptedonlytwo, and even then it pulled its punches. First, it authorized speeding up thetimetable forMark I plants to complywith the station blackout rule—but thiswas an easy call, since it did not involve new requirements. Second, thecommissiondecidedtotakeactiononhardenedcontainmentvents.But,reluctanttodirectlyconfronttheindustryonsuchasensitiveissue,theNRCgaveMarkI

owners an offer they couldn’t refuse: install hardened containment ventsvoluntarily or the NRC staff would conduct plant-specific backfit analysis todetermineiftheagencycouldlegallyrequirethemtocomply.

Thecommission’sofferpresentedaneasychoiceformostMarkIowners.Iftheyinstalledtheventsasavoluntaryinitiative,theywouldnothavetosubmitalicenseamendmenttotheNRCforapproval,andtheNRCwouldhavealmostnoregulatorycontroloverthevents.3AlthoughtheNRCsetbasicstandardsforthedesign, construction, maintenance, and testing of the vents, Mark I operatorswould be under no obligation to meet them. The NRC would also have noauthority to issue violation notices if it found problems, unless the ventsinterferedwithothersafetysystems. Incontrast, if theagencycouldshowthatthehardenedventspassedthebackfittest,itcouldforcereactorownerstoinstallandmaintainthemontheNRC’sterms.

Initially, owners of all but five reactors decided to voluntarily installhardenedvents.Fortheholdouts,theNRCfollowedthroughonitsthreatanddidbackfitanalyses,concludingthatitcouldrequireallfivetoinstallthevents.Fouroftheplantownersgaveupatthatpointand“voluntarily”compliedbeforetheywere forced to.The fifthowner—theNewYorkStatePowerAuthority—wenton the offensive, challenging the staff’s analyses and cost-benefit calculationsregarding its JamesA. FitzPatrick nuclear plant. This time, it was theNRC’sturn tobuckle.FitzPatrick, locatedonLakeOntarionear the townofOswego,becametheonlyMarkIBWRintheUnitedStatesthatdidnothardenitsvents.

TheNRCstaffauditedsomeofthehardenedventdesignsandinspectedthehardware and operating procedures after the ventswere installed.But the factthat the licensees had performed the work voluntarily severely restricted theNRC’sabilitytoensurethattheventswouldbeusablewhenneeded.

And there was good reason to believe that they wouldn’t be usable. Theventsweredesignedtooperateonlywithinthedesignbasisoftheplantandonlybefore core damage occurred. That meant that in the event of more severeconditions—high radiation fields, heat, or pressure—the vents might notfunction.AndtheNRCstaffdidnotevenrequiretheventstofunctionduringastation blackout, relegating that issue to future consideration in the IndividualPlantExaminationprogram.Onceagain,itwasonestepsideways.

AstotheremainingthreestaffrecommendationsforMarkIimprovements—alternate ways to inject water, improved reliability of reactor vesseldepressurization, and emergency procedures and training—themajority of the

commissioners supported the industry position that they should be folded intothe quasi-voluntary IPE program. Accordingly, later in 1989 the NRC sent aletter to Mark I licensees meekly stating that the NRC “expects” them to“seriously consider these improvements during their Individual PlantExaminations.”

Thislacklusterrequestreceivedalacklusterresponse.WhentheNRCfinallyreportedontheresultsoftheIPEsin1996,sevenyearsaftertheprojectbegan,itnoted that in several cases the licensees indicated that the containmentperformance improvements were being “considered, but do not identify therecommendationsascommitments.”MostoftheMarkIplantownersstatedthatthey alreadyhad alternatewater sources andmerely credited them in the IPE;somedidnotevenbothertocreditthem.Withregardtoemergencytraining,thelicenseessimplycommittedtovoluntaryindustryguidelines.Andwithregardtoenhancing the reactor vessel depressurization system, many licensees did notrespondatall.TheNRCclaimedvictoryinthosecaseswhenlicenseesactuallydid something,but itwaspowerless tocompelanyof them todomore;muchlesscoulditconduct thoroughreviewsandinspectionstoverifythatwhat theyhaddonewouldleadtomeaningfulsafetyimprovements.

One could hardly judge the outcomes of the Mark I containmentimprovement program and the IPEs to be successes. Yet they set a majorprecedent for dealing with severe accident issues through “voluntary industryinitiatives”(sometimesalsoconfusinglycalled“regulatorycommitments”).Likethe backfit requirements of the 1980s, thiswas in keepingwith the regulatorytrendsofthetimes,inwhichindustry“self-regulation”toolslikevoluntarycodesof conduct were increasingly used to forestall new government mandates,despite concerns about foxes guarding henhouses. For its part, the nuclearindustrynowcouldtoutitsvoluntaryactionsasexamplesofitscommitmenttosafetybeyondwhattheNRCrequired.

Oneofthekeyvoluntaryindustryinitiativesofthe1990swasthedevelopmentofSevereAccidentManagementGuidelines,orSAMGs.Thesewereemergencyplansplantoperatorsweretouseduringanaccidentinwhichcoredamagehadalready occurred or was imminent. (SAMGs were to be used if a plant’semergencyoperatingprocedures,whichincontrastwereregulatedbytheNRC,failed topreventcoredamage.) In1994, the industry,under theauspicesof itsnewly constituted advocacy group, the NEI, developed a guideline documentthatalllicenseespromisedtoadopt.Onceagain,however,becausetheSAMGs

werevoluntarypractices, theNRCwasvirtuallypowerless to ensure that theywouldbeworkableandthatplantworkerswouldbeappropriatelytrainedtousethem.4

Mark I containmentswere not the only ones that concerned theNRC; theMark II had similar issues. Also, another type of containment—theWestinghouse ice condenser, a PWR version of a pressure-suppressioncontainment—was vulnerable to failure in severe accidents, especially in theevent of a hydrogen explosion. (Although it required theMark I and II to beinerted with nitrogen gas, the NRC had not done so for ice condensers, oranother model of BWR called the Mark III.) Several years after Three MileIsland, theNRChad requiredownersof icecondensersandMark IIIplants toinstall igniters—similar to spark plugs—that could burn off hydrogenaccumulating in a containment before it reached an explosive concentration.However, those igniters required AC power to function, so they wouldn’t beavailable in a station blackout, a potentially major weakness. Even the goldstandard—large, dry PWR containments—might be vulnerable to accidents inwhichthereactorvesselfailedathighpressure.ButtheNRC’sfailuretoimposemeaningful changes on theMark I, perhaps theworst of the lot, did not bodewellforthefutureofthecontainmentimprovementprogram.

Overtime,theNRCstaffappearedtoloseitsappetiteforgrapplingwiththeindustryovernew requirements to reduce severeaccident risk.Evenworse, inresponsetogrowingpoliticalpressure,theNRCdecidedtosweepotherstubbornissuesundertherug.Infact,asThreeMileIslandrecededintothepastandnoother Western-designed reactor experienced an event to jolt the memory(Chernobyldidn’treallycount,asitwasconsideredanexoticSovietbeast),theagency in the 1990s embraced a sentiment that its requirements were not toolenientbutrathertoostrict.

Accordingtothislineofthinking,severeaccidentriskswerealreadysolowthatcertainregulationscouldbeweakenedwithoutsignificantlyaffectingsafety.The NRC dubbed this approach “risk-informed regulation,” and counted onprobabilisticriskassessmentdatatojustifywhatiteuphemisticallyreferredtoas“reducingunnecessaryconservatism”butactuallyamountedtoremovingsafetyrequirements. Risk-informed regulation was seen by critics (such as DavidLochbaumof theUnionofConcernedScientists)asa“single-edgedsword”: itwasonlyusedtoreduceregulatoryrequirements,nevertostrengthenthem.5

Reservations about the validity of probabilistic risk assessments faded as

moreandmoreutilitiesbegantousetheminregulatoryapplications.Andwhynot?Theyseemedtoenabletheutilitiestogetwhattheywanted:lessregulation.ButeventhoughPRAmethodologyhadadvanced,itstillsufferedfrommanyofthe same problems, including huge uncertainty factors when addressingearthquakes,otherexternalevents,and reactorshutdowns (when the riskofanaccident can be surprisingly high).Again, the tendency of theNRC and plantowners when confronted with these uncertainties was to downplay or ignorethem. As a result, safety decisions based on PRA analysis did not accuratelyaccount for the risks of these additional hazards.Themisuse of PRA analysisdid,however,lendcredencetotheconcernsJamesAsselstineraisedinhis1985voteontheSevereAccidentPolicyStatement,whenheaccusedhiscolleaguesof deliberately ignoring uncertainties to minimize risks: “the Commissionchooses to rely on a faulty [risk] number which supports the outcome theyprefer.”

Take the issueofdevelopingareliablePRAforanearthquake,whichveryfew plant owners have done. To perform the assessment properly one wouldneed accurate estimates of the likelihoods of earthquakes at each magnitude;detailedmodelsoftheeffectthataquakeofeachmagnitudewouldhaveonplantstructures;andadefensibleanalysisofhowtheearthquakedamagewouldaffectplant operation and the ability of operators to carry out manual actions.Assembling this informationwouldbeadaunting task,and theuncertaintiesateverystepwouldbeformidable.ThereislittlewonderthattheindustryhashaddifficultytacklingseismicPRAs.6

Amongthefirst regulations that theNRCset itssightson“risk informing”wasapost–ThreeMileIslandrequirementthatallreactorsinstall“recombiners”that could prevent the accumulation of hydrogen during a loss-of-coolantaccident. In reconsidering the requirement for the Mark I and II, the NRC’sanalysis found that the recombinerswould not be needed to prevent hydrogenexplosions during the first twenty-four hours after an accident because thereactor containments were inerted with nitrogen. However, the recombinerscouldbeuseful after twenty-fourhourshadpassedbecause the inertingwouldbecome ineffective.7Nonetheless, in2003 theNRCeliminated the recombinerrequirement, concluding that removing this equipment would not be “risksignificant.”Thereason:theSAMGsatthoseplantscalledforoperatorstoventorpurgehydrogeninasevereaccident,andtheNRCbelievedthattwenty-fourhours gave them plenty of time to prepare to get that done. Based on this

calculation,theagencyconcludedthatthemonetaryvalueoftheincreasedthreatto public health was less than what the utilities would save by not having tomaintaintherecombiners—$36,000peryearperreactor.

Thus the NRC removed regulatory requirements to prevent hydrogenexplosionsinpartbytakingcreditforvoluntaryinitiatives—SAMGs—thatitdidnot regulate. This type of twisted logic was typical of the risk analysis thatenabled theNRCtoweaken its regulationsat thebeginningof the twenty-firstcentury.

IntheyearsfollowingThreeMileIsland,theJapanesecloselystudiedtheNRC’sregulatory reforms, and inmany cases emulated them. Japan’sNuclear SafetyCommission identified fifty-two lessons learned fromThreeMile Island that itrecommendedforadoptioninJapan’sownsafetyregulations.JapanalsobegantodevelopsevereaccidentcountermeasuresafterChernobyl.AmongthosethatTEPCOincorporatedatFukushimawerehardenedvents,modificationstoallowuseoffire-protectionpumpstocoolthecoreifneeded,andmeasuresforcopingwithstationblackoutsofmodestlength,includinglossofDCpower.

The Japanese also developed severe accident guidelines, referred to asaccident management (AM) measures, using the results of probabilistic riskassessments conducted by research organizations. In short, there were manysimilaritiesbetweenactionstakenintheUnitedStatesandthoseinJapan.

Japan’s severe accident management measures also shared many of thedefectsoftheU.S.approach.AlloftheAMmeasureswererootedinthebeliefthatthepossibilityofsevereaccidentswassolowasnottobe“realisticfromanengineering viewpoint”; hence these steps were not considered essential.Consequently, theNSCconcluded that “effectiveaccidentmanagement shouldbe developed by licensees on a voluntary basis,” and the utilities accordinglydevelopedAMmeasuresontheirown.

As a result, no regulator assessed whether the plant owners’ assumptionswere realistic regarding the ability ofworkers to carry outAMmeasures likehardenedventoperationandalternatewaterinjection.Inparticular,nooneaskedTEPCOwhyitsAMproceduresweredesigned tocopewithastationblackoutthat would last only thirty minutes and affect only one reactor at a site. Ifsomeonehad,perhapsTEPCOwouldnothavehadtoconcedeafterFukushimathat the tsunami and flood resulted in “a situation that was outside of theassumptionsthatweremadetoplanaccidentresponse.”

SupposethatdecadesagotheNRCstaffhadsucceededinpushingthroughamuch more aggressive approach for dealing with Mark I core damage andcontainment failure risks, including the challenges of a prolonged stationblackout.ThereisnoguaranteethattheJapanesewouldhavefollowedsuit,buttheywouldhavebeenhard-pressedtoignoretheNRC’sexample.TheNRCstaffinthe1980shadallbutpredictedthatsomethinglikeFukushimawasinevitablewithout the fixes it prescribed, but the agency’s timidity—or perhaps evennegligence—contributed to the global regulatory environment that madeFukushimapossible.TheNRC’srelianceon theflawedassumption thatsevereaccidentrisksareacceptablylowhelpedtoperpetuateadangerousfallacyintheUnitedStatesandabroad.Ultimately,theNRCmustbearsomeresponsibilityforthe tragedy that struck Japan. And the commissioners must acknowledge thatunlesstheyfullycorrecttheflawedprocessesofthepast,theycannottruthfullytestifybeforeCongressthataFukushima-likeevent“can’thappenhere.”

10

“THISISACLOSEDMEETING.RIGHT?”

It was the last session of the NRC’s twenty-third Regulatory InformationConference. The RIC, as it is known, is an annual gathering that attractsregulators,utilityexecutives,industryrepresentatives,themedia,andothersfordiscussions of new and ongoing initiatives by the NRC. More than threethousandpeoplefromtheUnitedStatesandaroundtheglobe,includingateamof seismic experts from Japan, haddescendedon aMarriott conference centeracrossRockvillePikefromtheNRC’sWhiteFlintheadquartersforthethree-dayevent.

Now,astheconferencewaswindingdown,afewdozenpeoplehadgatheredto hear a panel discuss the latest results of an NRC research project entitledState-of-the-ArtReactorConsequenceAnalyses,orSOARCA,asitwascalledintheNRC’s acronym-rich environment. The takeawaymessage from the panel:evenifaseverenuclearpowerplantaccidentweretohappen—say,anextendedstationblackoutataMarkIboilingwaterreactor—itwouldn’tbeallthatbad.

ThedatewasMarch10,2011.By all accounts theRIChad been a great success, a reflection of how the

NRC’sstaturehadgrownalongwiththeimprovingfortunesofnuclearpowerintheUnitedStates.Afterdecadeswithoutanewreactororderbeingplaced, theUnitedStatesinrecentyearshadbeguntoseearesurgenceofinterestinnuclearenergy,spurredonbypolicymakers,pundits,andindustryboostersaddressingapublicthathadlargelyforgottenthenuclearfearsofthreedecadesearlier.Theyargued that the atom was the only realistic alternative to greenhouse gas-belching fossil fuel plants for delivering large amounts of power to anincreasingly energy-hungry world. That message was gaining traction, evenamongsomelongtimenuclearskeptics.

Nuclearenergy’sprospectswereboostedbyCongress in2005.Thatyear’sEnergy Policy Act (EPAct) contained energy production tax credits and loanguarantees tohelp insulateutility investors from the formidable financial risksthathadcrippledmanypastnuclearprojects.

Thanks to incentives such as these, the NRCwas soon besieged bymorenuclearplantlicenseapplicationsthanitcouldhandle.Tocopewiththeincreasein itsworkload, theagencyneeded toexpandsignificantly for the first time indecades.

By 2011, some of themomentum had been siphoned off by the persistentrecession,whichfrozecreditmarketsandreducedenergydemand,aswellasbythe ultracheap natural gasmade available by hydraulic fracturing. But the so-callednuclear renaissancewasverymuchalive in thenation’scapital. InterestremainedhighamongmanyinCongressandwithintheObamaadministration.1

Turnout for the 2011 RIC reflected the renewed support. The conferencereportedthehighestattendanceinitshistory,andsessionssuchasthosedevotedtothetechnologydujour—smallmodularreactorsthatcouldbeinstalledinallsorts of unlikely places around theworld—generated somuch excitement thatauditoriumsfilledtocapacityandpeoplewereturnedawayatthedoors.

As for thenagging issueof safety?That no longer seemed a showstopper,thanksinlargemeasuretosomedeftmessagingbythenuclearindustry,ledbythe NEI. The long-ago accident at ThreeMile Island represented the nuclearindustry of old; the accident atChernobylwas irrelevant toWestern designedand operated nuclear plants. An entire generation of Americans had reachedadulthood without encountering a major nuclear mishap. Perhaps things hadchangedwhenitcametonuclearsafety.

ThiswasallgoodnewsfortheNRC.Despiteitsofficialstatusasaneutralregulator,theNRChadbeendoingits

parttopromotetheimageofnuclearpowerassafe.SOARCAwasakeyelementinthatcampaign.ThegoalwastosupplantolderNRCstudiesthatestimatedtheradiological health consequences of severe reactor accidents. Many in thenuclearpowercommunity,bothinsideandoutsidetheNRC,believedthatthosestudies, dating backmore than twenty years, grossly exaggerated the potentialdanger.Antinucleargroupsweremisusingoldinformationtofrightenthepublic,theyargued.Itwastimeforanewcounteroffensive.

Inthe1980s,theindustryhadasserted—viathefindingsofitsownIndustryDegraded Core Rulemaking (IDCOR) program—that the NRC was wildly

overestimatingtheradiationreleasesthatcouldresultfromnuclearaccidents.Atthe time, theNRCstaff, bolsteredby the independent reviewof theAmericanPhysicalSociety,didnot concur.However, timeshadchanged.Now theNRCitselfwas leading the charge to reduce source terms. That gave rise to a newstate-of-the-artstudy:SOARCA.

Butin2011,afterspendingfiveyearsandmillionsofdollarsontheproject,the NRC had a new problem: the numbers SOARCAwas generatingweren’tcooperatingwiththesafetymessageagenda.ItwasdéjàvufortheNRC,whichhasgrappledwithhowtoexplainawayinconvenientfactsaboutnuclearpowerrisksoveritshistory.

In the RIC’s final hours, a panel of NRC experts clicked open theirPowerPoint presentations and provided a SOARCA update. Only the mostattentive would have noted a subtle change in the language describing thestudy’s findings—an attempt, perhaps, to glide past some of SOARCA’sunwelcomeresults.

Nooneintheroomcouldknowthatthesefindings,theoutcomeofcomputersimulations,wereabouttobeputtothetest.

Iftheconferencehadtakenplaceamonthlater,withFukushima’sdevastatedreactors still held in check by seawaterwhile thousands of refugees lamentedtheirpoisonedhomes,SOARCA’smessagewouldhavebeenfardifferent.Thepanelists would have known by then that the accident scenarios they hadanalyzedwereno longer just theoretical constructs, but insteaddescribed real-worldeventswithreal-worldconsequences.

Itwasnowclear that thereleaseofevenasmallfractionof theradioactivematerial in a reactor core was enough to wreak havoc around the world andfundamentally disrupt the lives of tens of thousands of people. This wassomething SOARCA, designed to calculate only numbers of deaths, was notcapableofpredicting.

Nearlythreedecadesearlier,inNovember1982,RepresentativeEdwardMarkeyof Massachusetts held a press conference in Boston with Eric van Loon,executive director of the Union of Concerned Scientists, to disclose troublinginformation: theNRCwassuppressingtheresultsofastudythatestimatedtheconsequences for human health and the environment of severe accidents foreverynuclearpowerplantsiteintheUnitedStates.

TheNRCstaffhaddraftedareportonthestudyforpublicconsumption,but

thecommissionhadbeensittingonitforoversixmonths.Atthetime,threeandahalfyearsafterThreeMileIsland,antinuclearsentimentsintheUnitedStateswererunninghigh.Thepossibility that theNRCwasengaginginsomesortofcover-upaboutrisksconfirmedthesuspicionsofmanyaboutthepronuclearbiasoftheagency.

Thestudy,performedbySandiaNationalLaboratoriesandgiven theblandtitle“TechnicalGuidanceforSitingCriteriaDevelopment,”soonbecameknownas the CRAC2 study, after the computer code it employed (“Calculation ofReactorAccidentConsequences”).Among the calculations in the studywas aprojection of the dispersal of large radioactive plumes from a severe accidentwithcontainmentfailureandanestimationoftheresultingcasualties.

Like a civilian version of the models used by Cold War–era militarystrategists that ranked the outcomes of thermonuclear conflicts in impersonaltermslike“megadeaths,”CRAC2wasusedtoquantifythedamagefromnuclearaccidents:thenumbersofradiationinjuries,“early”fatalitiesfromhighlevelsofradiation exposure, and “latent” cancer fatalities from lower and chronicexposures.

CRAC2andother radiologicalassessmentcodes, likeJapan’sSPEEDIandtheNRC’sRASCAL,utilizecomplexmodelstoestimatedosestoindividualsbysimulating the way radioactive plumes released by a nuclear accident aretransported through the atmosphere and the biosphere. CRAC2 went beyondthoseother codesbyusingmoredetailedmodels of thewayspeople couldbeexposed: external irradiation by radioisotopes in the air and on the ground,inhalation,andconsumptionofcontaminatedfoodandwater.

CRAC2alsohadacrudemodel forestimating theeconomicconsequencesassociated with land contamination, addressing issues such as lost wages andrelocation expenses for evacuees, and costs of cleanup or temporarycondemnation of contaminated property. What it couldn’t estimate werenonquantifiable consequences such as the psychological impacts on peopleforced to leave their contaminated homes and businesses either temporarily orpermanently.

RadiologicalassessmentcodeslikeCRAC2mustincorporatemanymovingparts—plumes are traveling, radioactive particles are being deposited, and thepopulation itself is not sitting still. Each calculation requires the input ofhundredsofparameters,fromsourcetermstotypesofbuildingmaterialstothemovement of evacuees and, eventually, even to the long-term effectiveness ofdecontamination efforts and the radiation protection standards governing

people’sreturntotheirhomes.Consequently,theresultsareveryuncertain.Fartoo often, however, the tendency among regulators has been to endow theseroughestimateswithmoreauthoritythantheydeserve.

Oneofthelargestsourcesofuncertaintyisweather.Sometypesofweathercouldbemuchmorehazardousthanothers,depending,forexample,onwhetherthe windwas blowing toward heavily populated areas andwhether there wasprecipitation. But theNRC’s as yet unreleased CRAC2 draft report containedonlyaveragesforweatherconditions.

WhatEdMarkeyandEricvanLoonpresented to reporters thatNovemberday were not just the averages but the “worst case” results for the mostunfavorable weather, such as a rainstormwashing out the plume as it passedoveralargepopulationcenter.Intheseprojections,the“peak”earlyfatalities,astheywerecalled,werefargreaterthantheaveragevaluesintheNRCreport.Thenumberswereinfactshocking:fortheIndianPointplant,thirty-fivemilesfrommidtownManhattan,aworst-caseaccidentcouldcausemorethanfiftythousandearlyfatalitiesfromacuteradiationsyndrome.Incontrast,theaveragevalueforearlyfatalitieswas831.

The NRC had held on to the draft CRAC2 report for over half a year,presumably because officials worried that even the average-value casualtyfigureswouldbetoomuchforthepublictoswallow.Markey’sdisclosureoftheworst-casespreadsheetforcedtheNRC’shand,anditfinallyreleasedthereportthatsameday.Thecommissionwasquicktodefenditsdecisionnottoincludetheworst-caseresults,offeringarationalethatwouldbecomefamiliarovertheyears: the chances of an accident severe enough to produce such death anddestructionweresoslightas tobehardlyworthmentioning.Or,as theNRC’sheadofriskanalysis,RobertBernero,saidat thetime,thelikelihoodofworst-case conditions was “less than the possibility of a jumbo jet crashing into afootballstadiumduringtheSuperbowl.”

Forthenexttwodecades,thislineofreasoningformedthebackboneoftheNRC’s strategy for addressing the threat of severe accidents—namely, thatevents threateningmajor harm to the publicwere so unlikely that they didn’tneed to be strictly regulated, a view shared by Japanese authorities and othermembersofthenuclearestablishmentworldwide.

In its risk assessments, the NRC was careful always to multiply high-consequence figures by tiny probabilities, ending upwith small risk numbers.Thatway, instead of having to talk about thousands of cancer deaths from anaccident,theNRCcouldprovidereassuring-soundingriskvalueslikeoneinone

thousand per year. TheNRCwas so fixated on this point that it insisted thatinformationaboutaccidentconsequencesalsohadtorefertoprobabilities.2

However, critics argued that the probability estimateswere so uncertain—and there was so little real data to validate them—that the NRC could notactuallyprovethatsevereaccidentswereextremelyunlikely.Therefore,accidentconsequencesshouldbeconsideredontheirownterms.

In any event, the low-probability argument became less relevant in theaftermathoftheSeptember11aircraftattacks,whenthepublicbegantowonderwhatmighthavehappenedhadalQaedadecidedtoattacknuclearpowerplantsthatday insteadof theWorldTradeCenterandthePentagon.NolongercouldonesaywithastraightfacethatajumbojetcrashingintotheSuperBowlwasaone-in-a-billion event—if the pilot were intent on doing it deliberately. Therewasnocrediblewaytocalculatetheprobabilityofaterroristattackandcomeupwith a meaningful number. The NRC had long acknowledged this, andconsequently did not incorporate terrorist attacks into its probabilistic riskassessmentsorcost-benefitanalyses.

Nolongerabletohidebehinditslow-probabilityfigleaf,theNRCstruggledtoreassureAmericansthattheyhadnothingtofearfromanattackonanuclearpower plant. While maintaining that nuclear reactors had multiple lines ofdefense,fromrobustcontainmentbuildingstohighlytrainedoperators,theNRCalsohadtoconcedethatthereactorswerenotspecificallydesignedtowithstanddirecthits fromlargecommercialaircraft,and that itwasnotsurewhatwouldhappen if such an attack occurred. The industry steered the public discussiontoward the straw-man issue of whether or not the plane would penetrate thecontainment—it couldn’t, according to the NEI—even though many expertspointed out that terrorists could cause ameltdownby targeting other sensitivepartsofaplant.

Tolearnmoreaboutwhatcouldhappeninanattack,theNRCcommissioneda series of “vulnerability assessments” from the national laboratories, but theresults remained largely classified for security reasons.Aside from a series ofcarefully constructed andvaguely reassuring talkingpoints, theNRCprovidedfewdetailsbeyond“Trustus.”Communitiesnearnuclearplantswouldgetfewtangibleanswersaboutthevulnerabilityofreactorsintheirmidst.

Meanwhile,the9/11disasterhadprovidedanopeningforenvironmentalandantinucleargroups toonceagain raise the safetyconcerns thathad faded fromviewsinceChernobyl.InthevacuumofnewpublicinformationfromtheNRC,

activistsfoundamplefodderintheoldCRAC2studyanditsreferencesto“peakfatality” and “peak injury” zones. Among themwas the organization HudsonRiverkeeper,campaigning toshutdowntheIndianPointplant. Interpreting theCRAC2resultsliberally,theorganization’sleader,RobertF.KennedyJr.,spokeofdangers to themanymillionsofpeoplewithinwhathereferredtoasIndianPoint’s“killzone.”

Such talk was deeply upsetting to one NRC commissioner in particular:EdwardMcGaffigan. A voluble, intellectual, and pugnacious former diplomatandSenatedefenseaide,McGaffiganbeganhis tenureontheNRCin1996byextending open channels of communication to the public. But after 9/11 hebecameopenlyhostiletowardanyonehebelievedwasexaggeratingthedangersofnuclearpowerormisinterpretingtheresultsofNRCtechnicalstudies.

“Themediaholdsus toaveryhighstandard, thatwhatwesay is factuallytrue . . . but theantinucleargroups . . . basicallyget awaywith sayingalmostanything,howeverfactuallyuntrue it is,”McGaffigan toldagatheringofNRCstaffin2003,adding,“Thewaywefixitisweworkaggressivelytogetourstoryout.”Thestory,inhisview,wasthatnuclearpowerwassafe.Thosewhoarguedotherwiseweremisinformedandmisguided.

McGaffigan was not alone in his frustration; other commissioners alsoaccusedcriticsofscaretactics.ButMcGaffiganwentfurther,mockingmembersofthepublicwhoexpressedtheviewshedisdained.

McGaffigan’sviewsworriednuclearwatchdoggroups.Afterall,howcouldaregulatorbetrustedtomakethedecisionsnecessarytoprotectpublichealthifhehadsuchabsolutefaithinthebenignnatureofthefacilitiesheoversawanddidnotworryabouttheeffectsoflow-levelradiation?

ButtherewasmoretoMcGaffigan’scrusade;heaccusedtheNRCstaffitselfofoverstatingthehazardsofnuclearaccidents.Inhisview,disinformationwascoming from inside the agency as well as from hostile critics elsewhere. Thestaff’stechnicalanalyses,hesaid,weremakingunrealisticallydireassumptions.Onecase inpointwas the riskposedbyspent fuelpools,a subject thatwouldsurgetorelevancyinlittlemorethanadecadeatFukushimaDaiichi.

Edward McGaffigan, who was an NRC commissioner from 1996 to 2007. U.S. Nuclear RegulatoryCommission

InJanuary2001,theNRCstaffreleasedareport,“TechnicalStudyofSpentFuel Pool Accident Risks at Decommissioning Nuclear Power Plants,” orNUREG-1738.Thereportevaluated thepotentialconsequencesofanaccident,such as a large earthquake, leading to the rapid draining of a spent fuel pool.NUREG-1738 estimated that within hours such an event could cause azirconiumfire throughout thepool thatwould result inmeltingof the fuelandreleaseofa large fractionof its inventoryofcesium-137aswellas significantamountsofother radionuclides.The study found thatdozensofearly fatalitiesand thousands of latent cancer fatalities could result among the downwindpopulation.

Data from that study was later incorporated by outside experts into atechnical paper,whichwaspublished in2003 in the respected journalScienceand Global Security.3 The paper concluded that the U.S. practice of tightlypackingspentfuelinpoolswasrisky.Itcalledonutilitiestomovemostofthefuel to safer dry storage casks. In an angry response, McGaffigan called thepublication, based at Princeton University, a “house journal” of “antinuclearactivists.” He fumed that “terrorists can’t violate the laws of physics, butresearchers can.” But he also denounced NUREG-1738 itself, calling it “theworst”ofexcessivelypessimisticstaffstudiesonspentfuelvulnerabilities.

McGaffigan was so sure the Princeton study was wrong that, in aMarch2003 public meeting, he appeared to direct the NRC staff to rebut the studybefore the staff had completed its own analysis. Such interference by a

commissioner was practically unheard of. The NRC’s inspector generalinvestigated and concluded that McGaffigan had tried to exert inappropriateinfluenceontheresearchstaff.4

ItwasinthisoverheatedpoliticalenvironmentthattheSOARCAstudywasconceived.Theearly resultsof thenuclearplantvulnerabilityassessments thattheNRChadbeenconductingsince shortlyafter the9/11attacks indicated, intheagency’sview,thattheradiologicalreleasesandpublichealthconsequencesresultingfromterrorist-causedmeltdownsgenerallywouldn’tbeascatastrophicaspreviousstudies,includingCRAC2,hadfound.

Unfortunately for theNRC, it could not broadcast this goodnewsbecausethe vulnerability studies, being related to terrorist threats, were considered“classified”or“safeguards”information.ButsomeinsidetheNRCreasonedthatiftheagencyappliedthesameanalysismethodstoaccidentsinsteadofterroristattacks, itmightbeable tododge someof the security restrictionsandget theinformationouttothepublic.SOARCAwastheresult.

Therewasadownside.Openinguptheanalyticalprocesswouldalsoexposethestaff’smethodologyandassumptionstounwelcomescrutinybyoutsiders.SotheNRCplanned to keep a veil of secrecy over theSOARCAprogram itself,stamping the staff’s proposal for how to conduct the study, as well as thecommission’sresponse,as“OfficialUseOnly—SensitiveInternalInformation.”TheNRCwould control all information about the study and report the resultsonlywhen itwasready,and inamanner thatcouldnotbe—in its judgment—misinterpretedormisused.Fromtheoutset,onecommissioner,GregoryJaczko,objected,arguing that the studyguidelinesandother relateddocuments shouldbepubliclyreleased.Hewasoutvoted.

TheNRC’sconcernaboutmanagingtheinformationcomingfromSOARCAwasevidentfromthebeginning.Thecommissionerswantedthestafftodevelop“communicationtechniques”forpresentingthe“complex”resultstothepublic.Although the technical analysis had barely begun, the first draft of thecommunicationsplanassertedthatnuclearpowerplantsweresafeandhadbeengettingsaferformorethantwodecades.Evenso,thecommissionersrejectedthedraft and continued to micromanage the message. The communications planwouldgothroughatleastsixrevisionsbeforetheyweresatisfied.

OnethemetheNRCwasdeterminedtoemphasizewasSOARCA’sscientificrigor.Asthenamesuggested,theprojectwastobeallaboutusing“state-of-the-art information and computer modeling tools to develop best estimates of

accident progression and . . . what radioactive material could potentially bereleasedintotheenvironment.”ButtheNRCOfficeofResearch,tryasitmightto be an independent scientific body, could never truly be free from thecommission’spolicyobjectives.Theresearchofficehadfacedaccusationsinthepast of trying to influence the results of studies performed by its contractorpersonnel.5Now,thecleardirectionfromMcGaffiganandotherseniorofficialswouldmakeitdifficulttoproduceacompletelyobjectivestudy.

Although by all appearances the purpose of SOARCAwas to reassure thepublicthatnuclearpowerwassafe,thenuclearindustrydidnotenthusiasticallyjump on board. Perhaps company executives did not relish the prospect ofanother CRAC2-like spreadsheet making an appearance, listing potentialaccidentcasualtyfiguresforeverynuclearplantinthecountry—arecipeforbadpublicity no matter how low the numbers. After all, Ed Markey was still inCongress,wagingbattlesovernuclearsafety.

TheNuclearEnergyInstituteinterceded,sendingtheNRCalistofforty-fourquestionsabouttheproject,includingasuggestionthatafictionalplantbeusedinstead of a real one. The SOARCA researchers soon found that very fewutilitieswere interested incooperatingwith theNRCon the study. (For addedmeasure,theNEIhintedthatanyvolunteerswouldwanttherighttoreviewhowtheirplantswereportrayed.)The initialplan toanalyze theentireU.S.nuclearfleet of sixty-seven plant sites was whittled down to eight and then to five;ultimately, only three were willing to participate. In the end, the NRC staffanalyzed just two stations: Peach Bottom in Pennsylvania, a two-unitMark IBWR,andSurryinVirginia,atwo-unitPWR.6

Withavast,complex,anduncertainty-riddenstudylikeSOARCA,itwasn’tnecessarytocommitscientificfraudtoguidetheprocesstoadesiredoutcome.Therewere plenty of dusty corners in the analysiswhere helpful assumptionscould be made without drawing attention. The NRC employed a number ofmaneuvers to help ensure that the studywould produce the results it wanted,selectivelychoosingcriteria—ineffect,scriptingtheaccident.

It discarded accident sequences that were considered “too improbable,”screening out events that would produce very large and rapid radiologicalreleases,suchasalargecoolantpipebreak.Itonlyevaluatedaccidentsinvolvinga single reactor, even though some of the events it considered, such asearthquakes, could affect both units at either Peach Bottom or Surry. Itconsideredits“bestestimate”tobescenariosinwhichplantpersonnelwouldbe

ableto“mitigate”severeaccidentsandpreventanyradiologicalreleasesatall;itanalyzedscenarios inwhichmitigationwasunsuccessfulbutpronounced themunlikely. Perhapsmost curious was the NRC’s decision to assume that lowerdosesof radiationarenotharmful—anassertionatoddsnotonlywithabroadscientificconsensusbutwiththeNRC’sownregulatoryguidelines.

The fog grew even thicker when the time came to decide how the studyresultswouldbepresented.First,thecommissionersdecreedthatfiguressuchasthenumbersoflatentcancerfatalitiescausedbyanaccidentshouldnotappear.Instead, the report would provide only a figure diluted by dividing the totalnumber of cancer deaths by the number of all people within a region. Forinstance,ifthestudypredictedonehundredcancerdeathsamongapopulationofone million, the individual risk would be 100 ÷ 1,000,000, or one in tenthousand. So rather than saying hundreds or even thousands of cancer deathswouldresultfromanaccident—guaranteedtograbafewheadlines—thereportwouldstatea lessalarmingconclusion.Andsince theNRC’sprobabilistic riskassessmentstudiesestimatedthatthechanceofsuchanaccidentwasonlyaboutoneinonemillionperyear,thecurrentrisktoanindividual—probabilitytimesconsequences—would be far less. To use the same example, it would be onemilliontimessmallerthanoneintenthousand,oramereoneintenbillionperyear: a number hardly worth contemplating. The communication strategy forSOARCA appeared to be taking its inspiration from the old Reactor SafetyStudy and its discredited comparisons of the risks of being killed by nuclearplantaccidentsversusmeteorstrikes.

But therewasmoreobfuscation.TheNRCwouldonlyreveal thevaluesoftheseresultsforaverageweatherconditions,andnotthemoreextremevaluesforworst-caseweather; thiswas the same strategy of evasion that had gotten theagencyinhotwaterwithCongressmanMarkeyandthemediabackinthedaysoftheCRAC2report.

The commissioners also told the researchers to drop their original plans toinclude calculations of land contamination and the associated economicconsequences. Earlier, the project staff had carried out such calculations forterroristattacksattworeactorsiteswithhighpopulationdensity—IndianPoint,north of New York City, and Limerick, northwest of Philadelphia—butapparentlydecidedtheydidnotwantthatkindofinformationtobemadepublic.According to a staff memo, the models that had been used produced“excessively conservative” results—meaning, in NRC parlance, that the

researchers thought the damage estimateswere unrealistically high.7The staffsaidthemodelsneededtobeupdatedtoobtaina“realisticcalculation.”

Some issues that emerged as the study progressed did not fit into thepredeterminednarrative.Forinstance,itwashardtoexplainwhyanearthquakeoramajorfloodstrikingthePeachBottomandSurrysites,eachfeaturingside-by-sidereactors,couldbeassumedtodamageonlyoneunitandleavetheotherunscathed.Logically,anaccident involvingbothunitswouldnotonly increasethesourceterm,oramountofradioactivematerialsreleasedtotheenvironment,butalsoforceoperatorstodealsimultaneouslywithtwodamagedreactors.And,astheanalystsnoted,“amultiple-unitSBO[stationblackout]mayrequiremoreequipment, suchasdiesel-drivenpumpsandportabledirectcurrentgenerators,thanwhatiscurrentlyavailableatmostsites.”

The analysts calculated that these scenarios had alarmingly highprobabilities. But instead of following the study guidelines and including thescenarios,thestaffdecidedin2008torecommendthatthecaseofdualunitsbeconsideredasa“genericissue”—aprogramwheretroublesomesafetyconcernsare sent to languish unresolved for years. (The NRC was still pondering therecommendationthreeyears laterwhenFukushimademonstratedthatmultiple-unitaccidentswerenotmerelyatheoreticalconcern.)

TheNRC’sindependentreviewgroup,theAdvisoryCommitteeonReactorSafeguards,wasnotamusedbywhatappearedtobeablatantattempttobiastheSOARCA study. In particular, it objected to the staff’s seemingly arbitraryapproach for choosing accident scenarios to analyze. It pointed out thatSOARCA’sgoodnewssafetymessagecouldbelesstheresultofimprovedplantdesign or operation and more the result of “changes in the scope of thecalculation.” Simply put, SOARCA had analyzed different accident scenariosfrom those used in earlier studies like CRAC2, and therefore it could not bedirectly comparedwith them.Although the final SOARCA resultsmight lookbetter, thatwas because SOARCAwas deliberately excluding the very eventsthatcouldcausealarge,fast-breakingradiationreleaseofthekindCRAC2hadevaluated.

TheNRCrebuffeditsAdvisoryCommittee’scriticismandcontinuedonthecourse the commissioners had set. In deference to public complaints that thestudy was being conducted in secret with no independent quality control, theNRCagreedtoformapeerreviewcommittee.However,theNRCchoseallthemembers, and the committee’s meetings were also held in secret. The public

wouldjusthavetotrustthatthecommitteewasdoingagoodjob.When the NRC staff presented preliminary results of the study to the

Advisory Committee in November 2007, it appeared that the staff hadsuccessfullyobtained the conclusions its bosseswanted.First, the staff judgedthat all the identified scenarios could reasonably be mitigated—that is, plantworkers, using B.5.b measures and severe accident management guidelines(SAMGs),wouldbeable tostopcoredamageorblockradiationreleases fromtheplant.Eveniftheyfailedtopreventtheaccidentfromprogressing,thenewswouldnotbetoodreadful:thereleaseofradioactivematerialwouldoccurlaterand likely be much smaller than past studies had assumed, resulting in“significantly less severe” off-site health consequences. And finally, theNRCstaff was so confident that it stopped the simulations after forty-eight hours,assumingthatbythenthesituationwouldhavebeenstabilized.

The results that theNRC staff presented to theAdvisoryCommitteewerestriking. While CRAC2 had found that following a worst-case or “SST1”release,8 acute radiation syndrome would kill ninety-two people at PeachBottom and forty-five at Surry, SOARCA found the number of deaths to beexactlyzeroatbothsites.Therewasnomagic—orfundamentalimprovementinreactorsafety—behindthisstunningdifference.TheNRChadjustfiddledwiththeclock.IntheCRAC2study,theradiationreleasebeganninetyminutesafterthe startof theaccident,beforemostof thepopulationwithin tenmilesof theplanthadtimetoevacuate,puttingmanymoreatrisk.ButtheNRChadchosenaccidentsforSOARCAthatunfoldedmoreslowly.Asaresult,formostoftheSOARCA scenarios, analysts assumed that the population within the ten-mileemergencyplanningzonewouldbelonggonebeforeanyradiationwasreleased.That way, by the time a release did occur, people would be too far away toreceivealethaldose,Thiswasnotanapples-to-applescomparisontotheearlierstudy.

HardertounderstandwerethefarlowernumbersofcancerdeathsprojectedbytheSOARCAanalysis,becauseevenpeoplebeyondtheten-mileemergencyplanning zone could receive doses high enough to significantly increase theircancer risk.Whereas CRAC2 estimated 2,700 cancer deaths at Peach Bottomand 1,300 at Surry for this group, SOARCA project staff told the AdvisoryCommittee that they had instead found twenty-five and zero cancer deaths,respectively.

That, too, involved sleight of hand—and some shopping around to find a

convenient statistic.Despite awidespread scientific consensus that there is nosafelevelofradiation,theNRCstaffdecidedtoassumethatsuchalevelindeedexisted:nocancerswoulddevelopuntilexposuresreachedfiveremperyear(ortenreminalifetime).Anyexposurebelowthatwouldbeharmless.

At a 2007 Advisory Committee briefing closed to the public, RandySullivan,anemergencypreparednessspecialistfortheNRC,letsliponereasonwhytheSOARCAstaffsawtheneedtousesuchanunconventionalassumption.Apparently, thestaffdidn’t like thenumbers itwouldget if itused thewidelyendorsedlinearno-thresholdhypothesis(LNT),whichassumesthatanydoseofradiation,nomatterhowlow,hasthepotentialtoleadtocancer.Itwasaneasychoice: assume a high threshold, predict many fewer cancers. Otherwise, thenumber of cancer deaths predicted by SOARCA would be so large it couldfrightenpeople.

At thebriefing,Sullivanacknowledged:“WecouldeasilydoLNT, justgoahead,issuethesourceterm,calculateitoutto1,000miles,runitforfourdays,assess theconsequencesfor, Idon’tknow,300yearsandsay2milliremtimes[the population within] 1,000 miles of Peach Bottom. What is that? Eightymillion people. . . . We’re going to kill whatever. This is a closed meeting.Right?Ihopeyoudon’tmindthedrama.

“So thenwe’ll say that our best estimate is that therewill bemany,manythousands . . .you’llhave2milliremtimes80millionpeopleandyou’llclaimthatyou’regoingtokillabunchofthem.”

ConsideringafiveremperyearthresholdultimatelyprovedtoomisleadingevenfortheSOARCAteamitselftotolerate,soiteventuallyevaluatedarangeof thresholds, including the LNT assumption of zero. But other optimisticassumptionsenabledtheteamtokeepthenumberssmall.A2009updatetothecommissioners informed them that the study continued to find off-site healthconsequences“dramaticallysmaller”thanthoseprojectedbyCRAC2.

SOARCAwas supposed to be a three-year project.But by the timeof theSOARCAsessionattheMarch2011RegulatoryInformationConferenceithaddraggedon fornearly sixyears. (CommissionerMcGaffiganwouldnot live tosee the fruits of the project’s labors—he died in 2007.) Addressing themethodological problems that theAdvisoryCommittee had criticized, runningnew analyses requested by the peer review panel, coping with problems withcontractors, and project mismanagement all contributed to repeatedpostponementsofthecompletiondate.ButperhapsthebiggesttimesinkwastheneedtoaddressmorethanonethousandcommentsfromotherNRCstaff,who

alsohadtroubleswallowingsomeoftheSOARCAmethodology.The unanticipated volume of staff comments was a clear indication of

internaldiscomfortwiththestudy.InJanuary2011,afterbeinginformedofyetanotherdelay requestedby the staff,OfficeofResearchdirectorBrianSheronwroteinane-mail,“[I]fwemissthisdate,Isuggestweallstartupdatingo[u]rresumes.”

One of the major internal disagreements had to do with SOARCA’sassumptionsregardingso-calledmitigatedscenarios—inplainEnglish,howfastandsuccessfullyoperatorscouldusetheemergencytoolsathandtowrestleanaccidenttoasafeconclusionandavoidaradiationrelease.CouldworkersreallystartandoperatetheRCICsystematPeachBottomwithoutgeneratororbatterypower, as the SOARCA project staff had confidently concluded? Could theyhookupandrunportablepumpsandgeneratorstorunsafetysystemsforforty-eighthours(thelimitoftheSOARCAanalysis)?

Asearlyas2007,projectcontractorsatSandiaNationalLaboratories,whichwas reviewing the SOARCA analysis, were questioning whether all theemergency equipment and procedures would perform as the NRC teampredicted.Sandiawantedwhatitcalleda“humanreliabilityanalysis.”

That year Shawn Burns, a senior technical staff member at Sandia, wrotewhatprovedtobearatherprescientlettertotheNRC:

TheprincipalinitiatingeventfortheLongTermSiteBlackout[atPeachBottom]. . . isaseismiceventofsufficientlylargemagnitude...tocausemassiveanddistributedstructuralfailures...therealism of relocating relatively large and heavy mitigation equipment . . . from their storagelocation(s) throughrubbleandotherobstacles to theirconnectionpoints in theplant isdifficult tosupport. Similar questionswould apply to the other plausible initiating events, includingmassiveinternalfloodorlargeinternalfire.

He went on to raise questions about other potential difficulties, includingunavailabilityofbackupcoolingwatersupplies,electricalconnectionproblems,difficultieswithinstrumentation,anddeadbatteries.

But theNRC commissioners had already spoken on this issue: emergencystrategies and equipment—the so-called B.5.b. measures—would work in theSOARCAscenarios.Whetherthiswasareasonableassumptiondidnotseemtofigureintotheirinstructions.

Theissuebotheredmanywithintheranksof theNRC,however.Computermodelswereonething;actualhands-onexperienceatthenation’sreactorswasan entirely different matter. Senior reactor analysts who work in the NRC’s

regionalofficesfortheOfficeofNuclearReactorRegulation,andwhohaveallhadpreviousexperienceasinspectorsinthefield,hadalessoptimisticviewofthefeasibilityof thesemeasures than theresearchersrunningcomputermodelsat NRC headquarters. The reactor analysts had seen the B.5.b equipment forthemselves.

TheAdvisoryCommitteeonReactorSafeguardsalsoexpresseddoubtsaboutthewaytheSOARCAreportseemedtotakethesuccessoftheB.5.bmitigationmeasures for granted. The committee asked whether the project staff hadactually “walked down” the emergencymeasures to determine if they’dworkunder extreme accident conditions. The answerwas no. Instead, the staff hadbased its conclusions on so-called tabletop demonstrations—that is, movingpiecesaroundatoymodelofeachplant.

Toquiettheskeptics,SOARCAstaffvisitedPeachBottominPennsylvaniaand the Surry plant in Virginia and examined the actual equipment. Internaldissentcontinued,buttheSOARCAstaffwentontoquestionthevalidityoftheconcernsofcriticsandconclude that,basedon thosewalkdownsat theplants,thelikelihoodofeverythingworkingwasevengreaterthanpreviouslythought.

Itwaseasytounderstandwhytheprojectteamwantedtobelievethatplantworkers had the ability to mitigate the severe accidents that were analyzed:everythingelseledtocoremeltdowns—albeitmoreslowlythanpreviousstudieshadfound.

AnexamplewastheSOARCAstaff’sanalysisofahypothetical“longterm”stationblackoutatPeachBottom,which is locatedabout forty-fivemiles fromBaltimore and eighty-fivemiles fromWashington,DC. The accident scenarioproceeded through a grim sequence of events. First, all electrically poweredcoolantpumpswouldstopworking.Usingbatteries,operatorscouldstartupthesteam-poweredRCICsystem,butafterfourhours,thebatterieswouldfail,andafteranotherhour,sowouldtheRCIC.Thetemperatureandpressurewithinthereactor vessel would quickly rise, and the safety relief valves on the vesselwould eventually stick open, steadily releasing steam.With nomakeupwateravailable to replace the steam, the fuel would be uncovered in a matter ofminutes.

Ataboutninehours, thefuelwouldstart tomelt,eventuallycollapsingandfallingtothebottomofthereactorvessel.Afterabouttwentyhours,themoltenfuelwouldbreachthevesselbottomandspillontothecontainmentfloor,whereitwouldspreadoutandrapidlymeltitswaythroughthesteelcontainmentliner.A few minutes later, hydrogen leaking from the containment into the reactor

buildingwouldcauseanexplosion,openinguptherefuelingbayblowoutpanelsandblowingapartthebuilding’sroof.

Ifbatterieswerenotavailableforthosefirstfourhours—iftheywerefloodedfromtheadjacentSusquehanna,forinstance—theresulting“shortterm”stationblackout would be even worse. In that case, the models predicted that coredamagewouldstartafteronehourandthecontainmentwouldfailateighthours.

In either case, once the containment failed a plume of radioactivitywouldescapethedamagedplantandoverspreadthearea.Asexpected,thecalculationspredictednoearlyfatalitiesfromacuteradiationsyndrome.Butthelatentcancerfatalitynumberstoldanotherstory.EarlySOARCAdatasupposedlyhadshowedthat health consequences were “dramatically smaller” than those predicted byCRAC2. After the SOARCA staff was repeatedly criticized for makingassertions like these without ensuring that the two studies were consistentlycompared, analysts ran new calculations to see what would happen ifSOARCA’s methodology was applied to a CRAC2-sized release at PeachBottom and compared to the SOARCA result for a station blackout. Theoutcome?Thedifferencesinlatentcancerriskwerenotthatdramatic.9

WithinfiftymilesofPeachBottom, theestimatednumberofcancerdeathscausedbyashort-termstationblackout,averagedoverweathervariations,wouldbe 1,000, compared to the 2,500 projected by CRAC2 for a much largerradiation release. From a statistical standpoint, given the uncertainties, thedifferencewasmeaningless.Andfromahumanstandpoint,1,000deaths,whilelessthan2,500,wasstillaprettyunacceptablehealthconsequence.Ratherthandiscrediting the old CRAC2 analysis, the SOARCA study had in importantrespectsvalidatedit.10

For the small crowd gathered at theMarriott onMarch 10, 2011, to hear anupdate on SOARCA, some key details were missing. The NRC was stillunwilling to release the numbers publicly.Anyonewhowanted to knowwhatwasgoingonhadtoresorttoKremlinologytointerpretthesubtlechangesinthestatementsthattheNRCapprovedforrelease.

Twoyearsearlier,atthelastSOARCAsessionattheRIC,JasonSchaperowof the study team had reported a preliminary conclusion that “releases aredramatically smaller and delayed” from those projected inCRAC2, news thathardlysurprisedanyoneintheroomwhohadbeenwatchingthedatacontortionsovertheyears.Butin2011,thestatementhadsubtlychanged.PatriciaSantiago,

the latest of several branch chiefs to oversee theSOARCA study, presented abulletpoint that“forcasesassumedtoproceedunmitigated,accidentsprogressmore slowly andusually [emphasis added] result in smaller andmoredelayedradiologicalreleasesthanpreviouslyassumed/predicted.”

Thewordusuallywaskeyhere. It left thedooropen to thepossibility thattherewerescenariosinwhichCRAC2’spredictionshadnotbeensofaroffbaseafterall:perhaps,forinstance,astationblackoutatPeachBottom.

Nor did Santiago repeat the now familiar statement about dramaticallysmallernumbersofcancerdeaths.Shenotedonlythat“individuallatentcancerriskforselectedscenariosgenerallycomesfrompopulationreturninghomeafter[the]eventisover.”Inotherwords,mostofthedosetothepopulationwouldbereceived not during the early stages of the accident by people exposed toradioactiveplumes,butlongaftertheaccidentwasoverbyevacueeswhohadnochoice but to return to their now contaminated homes to live, hardly aconsolation.

However, Santiago did highlight one SOARCA conclusion that had notchanged over the years: the accident scenarios analyzed as part of the study“could reasonably be mitigated, either preventing core damage or delaying/reducingtheradiationrelease.”

The nextmorning, all the tabletopmodels and computer runs and fingers-crossed assumptions that supported that conclusionwould face their first real-world test. At 11:40 a.m. on March 11, Jason Schaperow sent an e-mail toSantiago, his supervisor. “Today’s Japanese earthquake seems to have causedoneoftheSOARCAscenarios(long-termstationblackout).”

“Onthismorning’snewstheysaidnorelease,”Santiagoreplied.“Timewilltell.”

Computermodelersandanalysts love toobtainreal-timedata that theycanuse to validate the predictions of their models—except, perhaps, if they aresimulating disasters. Soon, the SOARCA team would watch as many of thecatastrophic events they had deemed improbable unfolded not on a computerscreen, but on a television screen. And in the process the limitations of theSOARCAapproach—theprojectinwhichtheNRChadinvestedsomuchtimeandmoneytowinoveraskepticalpublic—wouldbecomeevident.

Over the years as the SOARCA study progressed, it had revealed thepotential for a natural disaster to cause a truly horrific event: an accident thatinvolved multiple reactors, rendered most emergency equipment useless, and

contaminatedlargeareaswithradiationplumesfarbeyondemergencyplanningzones due in part to the vagaries of weather. Yet instead of taking action topreventsuchanaccident,theNRCconvinceditselfthateveniftheaccidentdidhappen,theconsequenceswouldbeminor.Difficultissuesweredisregardedorputoffforanotherday.

If the NRC had undertaken this study not as an exercise in reinforcingexistingbiases, but as a roadmap for identifying and fixing safetyweaknessesfromAmericatoJapan,SOARCA’smostdirepredictionsmightnothavemadethetransitionfromaPowerPointpresentationtoaneventthatshockedtheworld.

11

2012:“THEGOVERNMENTOWESTHEPUBLICACLEARANDCONVINCINGANSWER”

On January 18, 2012, protesters attempted to gain access to a closed-doormeetingofJapan’sNuclearandIndustrialSafetyAgency(NISA).Morethanahundreduniformedandplainclothesofficersarrivedtoquellthescuffle.Agreenand yellow sign held aloft by one of the well-dressed demonstrators read:“NuclearPower?Sayonara.”

BeforeFukushimaDaiichi,thatprospectseemedunlikely.Japanwasfirmlywedded tonuclearpower—economically,politically,andsocially.Butnow,astheconsequencesoftheaccidenttenmonthsearliercontinuedtounfold,tomanyJapanesethemarriagewasdifficulttodefend.Thedemonstratorsbeingjostledinacrowdedhallwayandchanting“Shameonyou”totheauthoritiessequesteredbehindthedoorswerepartofanew,vocalconstituencyintentonhavingasayonJapan’senergyfuture.Forthem,thepriceofnuclearpowerwasjusttoohigh.

Since theaccident,muchhadchangedacrossJapan;2012wouldbecomeayearmarkedbyprotests,uncertainty,andshiftingpoliticalallegiances.AlthoughFukushima Daiichi officially was in cold shutdown, the popular debate overnuclearpowerwas increasinglyactive.Onnumerousoccasions,publicopinionboiled over at politicians who seemed tone deaf to the concerns of averagecitizens.Thecountry’sleaders—ingovernmentandintheclannishprivatesector—appeareddeterminedtoclosethebookonthedisasterofMarch11asquicklyaspossibleandbeginrestoringtheroleofnuclearpowerasanessentialelementinJapan’seconomiclife.

Immediatelyupon takingoffice inSeptember 2011,PrimeMinisterYoshihikoNodahadmadehisviewsclear:Japanneedednuclearenergy.Nodaproposeda

middle ground—one that he hoped would ease public fears about livingwithnuclearpowerandcorporateJapan’sfearsoflivingwithoutit.

“[I]t isunproductive tograspnuclearpoweras adichotomybetween ‘zeronuclearpower’and‘promotion,’”saidNoda.“Inthemid-tolong-term,wemustaim to move in the direction of reducing our dependence on nuclear powergeneration as much as possible. At the same time, however, we will restartoperations at nuclear power stations following regular inspections, for whichsafety has been thoroughly verified and confirmed.” If the public could beconvincedthatJapan’sreactorsweresafe,perhapsthemarriagecouldbesaved.

The“howsafeissafeenough”thresholdformanyJapanesehadsoaredinthemonthssinceMarch11,however.Innormaltimes,safetyinspectionshadbeenlargely pro forma, conducted out of view, with little or no public input.Everybodyhadseenwhatthatproduced.IfNodathoughthisproposaltorestartthenation’sreactorswouldwinpublicsupport,hequicklydiscoveredotherwise.

Withindays,tensofthousandsofprotesterstooktothestreetsofTokyo.TheSeptember19,2011,protestwasthelargestpublicdemonstrationinyearsinthecapital.TheywantedeveryreactorinJapanshutdownpermanently.Asignheldbyanelderlyprotesterdepictedamothercradlinganinfant.Itread:“Thischilddoesn’tneednuclearpower.”

OnSeptember19,2011,tensofthousandsofprotesterscloggedthestreetsofTokyo,demandinganendtonuclear power in the country. Here protestors gather at the Meiji Shrine Outer Garden in the nation’scapital.Wikipedia

•••

After being escorted out of their meeting room to avoid the noisy protestors,NISAofficials reconvened and approved the restart of two reactors at theOhinuclearplantinFukuiPrefecture,onJapan’swestcoast.Atthispoint,onlythreeof the country’s fifty-four reactors were still operating, and those would alsosoonbeturnedoff.Beforeanycouldberestarted,allwererequiredtopassthesafety checks first ordered by former prime minister Kan and now cited byNoda:afirstroundofgovernment-ordered“stresstests.”Plantsthatpassedthefirst-round testswould thenundergoasecond,morecomprehensive round thatwoulddeterminewhetherplantsweresafeenoughtocontinuetooperate.

Thefirst-stage testsweredesigned toverifya reactor’sability towithstandspecific events, such as beyond-design-basis earthquakes, tsunamis, or both.Takinga lead from theEuropeanUnion,whichordered stress tests forallonehundred thirty operating plants within its jurisdiction after the March 11accident, the Japanese government directed the nation’s utilities to performsimilartests.However,theguidelineswerevague,failingtospecifyclearlyhowfar beyond the design basis the assumed stresses should go. That made theoutcomesofthetestshardtointerpret.

The results of the first-stage tests were submitted to NISA, which thenpassedonitsplantrestartrecommendationstotheNuclearSafetyCommission.Thecommission,inturn,forwardeditsdecisiontotheprimeminister.Nodaandseveralofhiscabinetmemberswouldhavethefinalsay.

Evenasthegovernmentproceededthroughtheformalitiesofthestresstests,pressure was growing from several influential constituencies to bring thereactorsbackonlineasrapidlyaspossible.Arecurrentthemeamongtherestartsupporters was that Japan was headed for a major electricity shortage. Thatmomentwasapproaching,alongwith thehot,humidmonths,whenenergyusenormallywould rise by about 50percent.UnlessOhiUnits 3 and4—the firstreactorsinlineinthestresstestreviewprocess—wererestarted,JapanwouldbenuclearfreeonMay6,2012.

Thatprospectposedaworrisome“what if?” for restart advocates.SupposeJapan successfully made it through the summer without nuclear power. Thatwouldmake itmore difficult towin public support for returning the plants toservice.

ToaddcredibilitytoNISA’sconclusionthattheOhireactorsweresafe,theNoda government invited a delegation from the IAEA to review the findings.Basedonapreliminaryassessment,theIAEAreportedthatthestresstestswere“generally consistent” with its own safety standards and supported “enhanced

confidence”inthereactors’abilitytowithstandevenadisastersimilartothatofMarch11.

ThosefindingsdrewascathingpublicrebukefromtwonuclearexpertswhoservedasNISAadvisors.Thetests,thetwomensaid,failedtotakeintoaccountcomplex accident scenarios as well as critical factors such as human error,designflaws,oragingequipment.Atanewsconference,MasashiGoto,aformerreactor designer, labeled the stress tests “nothing but an optimistic desksimulation based on the assumption that everything will happen exactly asassumed.”1GotoalsoarguedthatthestresstestmethodsshouldfirstbeappliedtoFukushimaDaiichitoseeiftheycouldcorrectlysimulatetheoutcomeoftheaccident.

The other expert, Hiromitsu Ino, a professor at the University of Tokyo,accused the IAEA of simply rubberstamping NISA’s decision because of theinternationalagency’sdualroleasregulatorandpromoterofnuclearpower.Inonoted that the IAEA had deemed the Kashiwazaki-Kariwa nuclear plant safeaftera2007earthquakewithoutconductingafullexaminationoftheplant.

Ino’s and Goto’s sharp critiques were echoed two weeks later by anotherexpert: HarukiMadarame, the head of Japan’s NSC, who had been at PrimeMinisterKan’ssideduringtheheightoftheaccident.Inadeclarationthatmusthave surprised many, Madarame asserted forcefully that Japan’s nuclearregulatory framework was flawed, out of date, and below internationalstandards. He claimed that the government’s foremost concern was notprotectingthepublicbutpromotingnuclearenergy.MadarameaddedthatJapanhadbecomeoverlyconfidentinitstechnicalsuperiority,failingtoacknowledgethe risks that nuclear power posed, especially in an earthquake-prone country.Concerningthestresstestresults,hesaid:“Ihopethereisanevaluationofmorerealisticactualfigures.”

TheIAEA’sfinalreviewofJapan’sstresstests,releasedinMarch,appearedto support some of the critics’ concerns. The agency said that NISA had notcommunicatedwhat its desired safety levelwasor how the assessments coulddemonstrateit.Regardless,theIAEA’soveralljudgmentdidnotchange.

FormanyJapanese,theepiphaniesofsuchonce-staunchnuclearproponentsasKanandMadarameonlyheighteneduncertaintyandconfusion.BeforeMarch11, 2011, theyhadbeen led tobelieve that their country’s relianceonnuclearpower was a prudent choice. Now, knowledgeable insiders were painting theentirenuclear frameworkasapublic threatandanembarrassing fraud.Andat

thesametime,theleadershipinTokyowaspushingtorestartreactors.IfcriticismfromJapan’sownexpertswasn’tunsettlingenough,international

disapprobation soon followed. A group of experts summoned by YotaroHatamura’s investigative committee, which was wrapping up its lengthyassessmentoftheaccident,weighedin.BecausetheHatamurapanelfocusedonTEPCOandeventsatFukushimaDaiichi,muchofthecriticismwasdirectedattheutility,butthemessagespilledover:thefailingsweresystemic.Forexample,Richard Meserve, former chairman of the U.S. NRC and president of theCarnegieInstitutionforScience,said thatnotonlyhadTEPCObecomeoverlyconfidentbutJapaneseregulatorshadfollowedsuit,fallingvictimtothemythofsafety. “There has to be a willingness to acknowledge that accidents canhappen,”saidMeserve.2

AtthemomentTEPCOwasinafightforitsownsurvival.Acompanythatmanybelievedwastoobigtofailwouldsoonbecomeawardofthestate.Thiswas more than just a corporate icon falling on hard times. Soon, the cost ofTEPCO’slaxoversight,failedplanning,andpropensityforhigh-stakesgambleswouldshiftfromaprivatedebttoamassivepublicone.

Estimates of the cost of cleanup and compensation to victims of theFukushimaDaiichi accidentwerepeggedatmore than$71billion (6.6 trillionyen) by late 2012.Muchof that burdenwill fall on the shoulders of Japanesetaxpayers,alreadysufferingfromadeeplytroubledeconomy.

As Japanmarked the first anniversary of the FukushimaDaiichi accident, themagnitude of TEPCO’s financial woes was growing. The plunge in thecompany’sstockpricehaderasedalmost$39billioninmarketvalue,accordingto one analysis. Without an infusion of cash, the utility—which employed38,000peopleandsuppliedelectricitytoabout45million,includingthoselivingandworkingintheworld’slargestcity—almostcertainlywouldcollapse.

Private lenders and institutional investors were wary, wanting thegovernmenttocraftarescue.Noonecouldsaywithanycertaintyjusthowmuchthisallwasgoingtocost.RumorsthatthegovernmentwasgoingtonationalizeTEPCO were initially rebuffed by Trade Minister Yukio Edano. But aninterventionofsomesortincreasinglyseemedtobethegovernment’soptionofchoice—andTEPCO’sonlyhope.

Theutility’sleadersremaineddefiant,askingTokyoformoneybutrejectinganygovernmentsay incompanyoperations.Leading the fight tokeepTEPCO

under the control of insiders was its chairman, Tsunehisa Katsumata, one ofJapan’s best-connected business leaders. Although Katsumata planned to stepdown inashowof responsibility for theaccident,heargued thatonlyTEPCOexecutives knew how to run the company. Edano countered that TEPCO’scorporate culture “hasn’t changed at all” and that new management wasnecessary.

Some economists and energy experts sawTEPCO’s dire predicament as agolden opportunity to restructure Japan’s antiquated energy supply system bybreaking up utilitymonopolies and introducing competition. “Since the 1980sthe utilities have lookedmore like bloated government departments than red-bloodedbusinesses,”awriterforTheEconomistnoted.

Unlike energy markets in the United States and elsewhere, in whichgenerationanddistributionhadbeenseparated,openingthewayforcompetition,inJapanthetenregionalpowercompaniesheldtotalmonopoliesonallaspectsofenergysupply.The resultwas reliable servicebutat averyhighprice.Themonopolies were extremely lucrative for the utilities.3 An analysis byBloomberg News found that the ten of them earned $190 billion in annualrevenues fromgenerating, transmitting, and distributing power. Shattering thatstranglehold, some Japanese academics and international analysts believed,couldopenmarkets,reducerates,giverenewableenergyatoehold,andpossiblylessenJapan’sneedfornuclearenergy.

Tocriticsofthestatusquo,themonthsfollowingtheaccidenthadprovidedsome hope that change was possible. During the summer of 2011, thegovernmenthadimposedpowerrestrictionsonlargecorporateusers.Voluntaryconservation efforts had been surprisingly successful. Electricity consumptionduring steamyAugusthaddroppedbyabout11percent.Theusualchillof airconditioningwasgone,aswerecoatsand ties.Somemanufacturingoperationsmovedtooff-peaknightsandweekends.Evensomenightbaseballgameswereswitched to daytime. That led to speculation that reduced consumption couldbecomethenormandtherewouldbenoneedtorestartthereactors.Thenationstoodatacrossroads,activistsargued,needingonlyvisionaryleadershiptomapoutanewenergypolicy.

ButthosehopesgraduallyfadedasitbecameclearthatJapan,stillstrugglingtorecovernotonlyfromanucleardisasterbutfromamassivenaturaldisaster,wasunableorunwillingtotakeonsuchachallenge.Restructuringtheelectricitydistributionsystemwasnotapriority.KeepingTEPCOalivewas,however.

In lateMarch2012,TEPCOrequested$12billion (1 trillionyen) from thegovernmenttostayafloat.Theprice,ascompanyofficialsknew,wastheendoftheir independence; the government would take over control of the utility.4Breakingwith the utility’s long traditionof promoting executives from inside,the government brought in Kazuhiko Shimokobe, a bankruptcy lawyer andturnaround specialist, to be TEPCO’s chairman. Shimokobe, who had beenrunning thegovernment-backedTEPCObailout fund,wouldhandpick thenewpresident.“ThisisthelastchancetorestoreTEPCO,”hegrimlytoldreporters.

The ten-year bailout plan approved by the trade ministry in early Mayprovided $12.5 billion in government capital in exchange for more than 50percentofthevotingsharesofTEPCO,withtherighttoincreasethatpercentagetotwo-thirdsiftheutilityfailedtoinstitutemajorreforms.Inaddition,TEPCOhadtoagreetoacost-cuttingplanandotherchanges.Allsixteendirectorswouldresignandbereplacedbyanewboard,themajorityofwhosememberswouldbefromoutsideTEPCO.Thenewpresidentwouldbenotanoutsider,assomehadhoped,butNaomiHirose,aTEPCOmanagingdirectorwhoheldanMBAfromYaleUniversity.

TEPCO’s new management had to face a formidable challenge: a $9.78billionlossforthefiscalyearthatendedinMarch2012.Akeysteptomovetheutility back toward solvency was the restart of its seven reactors at theKashiwazaki-Kariwa plant, three of which had been idle since the 2007earthquake.“[A]nyplanthatdoesnotincludenuclearenergywouldbenothingmore thanapie-in-the-skyblueprint,” saidShimokobe,whoalongwithHirosewasslatedtoofficiallytakeoverfollowingshareholderapprovalinlateJune.

BylateJune,whenJapan’spowercompaniesheldtheirannualmeetings, itwasevidentthatTEPCOwasn’ttheonlyutilityopposedtoanuclearphaseout.Shareholder proposals to reject nuclear powerwere soundlyvoteddownat allthe meetings. Unsurprisingly, the utilities’ main institutional investors—lifeinsurers and banks—votedwith the companymanagements on this issue. Thestatus quo seemed to them a safer bet. In the end, stockholders approved thebailoutplanandtheongoingcommitmenttonuclearpower.

Indeed, the recovery plan barely mentioned any energy strategies beyondrestartingtheutility’snuclearplants.TheinfluentialAsahiShimbuneditorializedthat TEPCO was getting off too easily. The utility should be forced intobankruptcy and the company’s shareholders and creditors should be “made topay the price for their ownmistakes.” Only thenwould it be right to tap the

Japanesepublicforhelpinarecovery.

AsofMay6,2012,Japanhadnooperatingreactors.Withoutthem,thesystemwas shy of roughly fifty gigawatts of generating capacity—aboutwhat Tokyoconsumesduringpeakperiods.Withnonuclearpowerinthemix,Japanwouldrequireanadditionalthreehundredthousandbarrelsofoileveryday,alongwithan annual import of 23 billion cubicmeters of natural gas tomeet electricitydemand,according to InternationalEnergyAgencyestimates. (Thecostof thisimported fuel was expected to more than double residential electricity billsacrossJapanandfurtherhobblethenation’stroubledeconomy.)5

Although the media had spent months speculating about a Japan withoutnuclearpower,othersneverdoubted that the reactorswouldeventually restart,given the depth of institutional support for nuclear energy.OnMarch 23, theNuclearSafetyCommissionruledthatthestresstestsperformedonOhiUnits3and 4 were satisfactory. And on April 13, Noda announced that the two Ohireactors could safely resumeoperation.All that remainedwas the approval oflocal officials, no longer a sure thing for those who saw the devastationFukushimahadbroughttonearbycommunities.

This rush to fire up the reactors made no sense to many in Japan. Theaccident at Fukushima Daiichi was still being investigated and many criticalquestions remained unanswered. The current regulatory system had clearlyproven itself inadequate, yet the creation of a new agency to replace thediscredited NISAwas tied up by political infighting. For now, safetymattersremained in thehandsofNISAand theNSC—thesametwoagencies thathadsaid Japan’s reactors were failure proof. If restoring public trust was thegovernment’s top priority, many asked, what was the rush? Why not awaitcreationof thenewsafety agencyandgive it the authority todevelop its owncriteriaforrestarts?

AddingtoworrieswasthereleaseofnewseismicdatashowingthatalargeportionofwesternJapan,includingTokyo,wasvulnerabletoearthquakesnearlytwice as large as what the government had projected just nine years earlier.CoastalareasalongthissamepartofJapanalsowerefoundtobevulnerabletotsunamisofthirty-twofeet(tenmeters)ormore,threetimeshigherthanpreviousprojections. The area around theHamaoka nuclear plant, southwest of Tokyo,could be hit by a tsunami of sixty-eight feet (twenty-one meters), far aboveprevious predictions. Unlike remote Fukushima, this region was densely

populated.The data also identified previously unknown and potentially active faults

located in areas near or even directly underneath, Japanese reactors, includingOhi. Evenwhen presentedwith the new seismic information, the utilities andgovernment dismissed the potential hazards as exaggerated, withoutdocumentingtheirclaims.

“[I]sitreallypossibletoensurethesafetyofoperatingthesereactorswhilethe possibility of active faults lying beneath them cannot be ruled out?” theAsahiShimbunasked inaneditorial.“Thegovernmentowes thepublicaclearandconvincinganswertothisquestion.”

•••

The Ohi nuclear plant sits along Japan’s scenic west coast, about sixtymilesnortheastofOsaka,Japan’sthird-largestcity.Comprisingfourpressurizedwaterreactors, the plant is owned by Kansai Electric Power Company (KEPCO),whichreliesonnuclearpowerforalmosthalfitsgeneratingcapacity,morethananyotherJapaneseutility.OhiUnits1and2areolderPWRswithice-condensercontainments that are smaller and weaker than the large, dry containments atUnits3and4.Perhapsforthatreason,KEPCOproposedrestartingonlyUnits3and4atfirst.

Inmanyrespects,Ohiservedasanidealtestcaseforboththosepromotingandthoseopposingtherestarts.TheplantisinFukuiPrefecture,hometoatotalof thirteenreactors.Thelocaleconomywasheavilydependentonthejobs, taxrevenues, andgenerous perks provided to local communities byutilities doingbusiness there. Some of Japan’s largest manufacturers, including SharpCorporationandPanasonic,areKEPCOcustomers.ThepossibilitythattheyandothersmightmoveoperationsoffshoreifuncertaintyregardingenergysuppliescontinuedwasaclearconcerninTokyo.

Despitetheireconomicbenefits,notallneighboringcommunitieswereeagertoseetheOhireactorsreturnedsoquicklytoservice.Havinganuclearneighboronceseemedattractivetonearbytowns,butthatwasbeforetheyhadwitnessedtheconsequencesofanaccident—thedepopulationofalargeregion,widespreadcontamination, health risks, uncertainty about a return to normal life. At theheight of the restart debate, the government announced that 18 percent of allFukushimaevacuees—includingthoseasfarasthirtymilesaway—mightnotbeabletoreturntotheirhomesfortenyearsbecauseofradiationlevels.

Asaresult,somearguedthatifcommunitiestensorevenhundredsofmilesawaywerevulnerable tonuclearplantaccidents, theytooshouldhaveasayintheplants’operation.Andthecalculusmightbedifferentforsuchcommunities,sincetheywouldbeexposedtotheriskswithoutreceivinganyof thebenefits.ThatwassomethingnewinJapan.

One of the most outspoken restart critics was Toru Hashimoto, the brashyoung mayor of Osaka, whose city was Ohi’s largest customer and also thelargest shareholder in KEPCO. Hashimoto argued that the government wasprematurelypushingtherestartsattheexpenseofpublicsafety,acontentionthatcatapulted him into the national spotlight and earned him a large following.DissatisfiedwithTokyo’sassurances that theplantwassafe,Hashimotosetuphisownpanelofexperts,who took issuewith theadequacyof thestress tests.ThatpromptedgovernorsoftwonearbyprefecturestodemandamorethoroughinquiryintoOhi’ssafetybeforeUnits3and4werereturnedtoservice.

CriticsnotedthatthestresstestsrepresentedjustthefirstphaseofwhatwassupposedtobeamultipartsafetyresponsetotheFukushimaaccident.Additionalmeasures—constructionofhigherseawalls,betterprotectionagainstearthquakedamage, improved emergency planning, filtered venting systems—could takeyearstocomplete.Inthemeantime,however,theplantswouldbeoperating.

Withoppositionfromlocalofficialsandweeklydemonstrationsinthecapitalthreatening to derail plans for a quick restart at Ohi, Prime Minister Nodasteppeduptherhetoric.“Japanesesocietycannotsurvive”withoutthereactors,hewarnedonnationaltelevision.Andheofferedassurancesthatthegovernmentwould“continuemakinguninterruptedefforts”toimprovenuclearsafety.

ThegrowingpressurefromTokyoandJapan’sbusinesscommunityhaditseffect. Local government opposition to the Ohi restart faded, with officials,includingHashimoto,agreeingtoa“limited”restartatleastthroughthesummermonths.

OnJune16,theNodagovernmentofficiallygavethego-aheadtorestartOhiUnits3and4.TradeMinisterYukioEdanoacknowledgedpublicopinionpollswere running solidly against the restart. “We understand that we have notobtainedallofthenation’sunderstanding.”

Thatwasevidentsixdayslater,whenanestimated45,000peopleprotestedthedecisionoutsidetheprimeminister’soffice;thousandsofdemonstratorsalsorallied in Osaka and elsewhere. The following Friday, an even larger protestmassed in the capital near the primeminister’s office.As he left for the day,Noda shrugged off the protesters. “They’re making lots of noise,” he told

reportersbeforeheadinghome.ItwouldtakeseveralweeksforthetwoOhireactorstobebroughtfullyinto

service, in time to meet what the government had predicted would be a 15percentshortfall inenergysupplies inwesternJapanduringthehottestdaysofsummer.OnJuly16,withtemperaturesaboveninetydegrees,tensofthousandsof people clogged central Tokyo protesting the restart. Whether the giantdemonstrationwouldhaveanyeffectonJapaneseenergypolicywasuncertain.Butthecrowd,wavingbannersandholdingupsigns,madeclearthatitwastimethat thepublichadasay in thosedecisions.Asamarcher toldareporter,“It’sjust a big step forward to start raising our voices.” Despite the protests, inSeptemberthegovernmentauthorizedtheircontinuedoperation.

•••

In the United States, those who had hoped for change also were feelingfrustrated.AmongthemwastheNRC’sGregoryJaczko.

Shortly before leaving his job as chairman in July 2012, Jaczko offered acandidobservationtoaWashingtonaudienceofenergyinsiders:“Iusedtosaytheonethingthatkeptmeupatnightwasthethingwehadn’tthoughtof.Today,the things that keep me up at night are those things we know we haven’taddressed.”

It had been a year since the NRC’s Near-Term Task Force had made itsrecommendationsonaplanofaction,includingfar-reachingstructuralreforms.ButtheslowpaceofactualreformbotheredJaczko.

Althoughmany details of the FukushimaDaiichi accidentwere still beinganalyzed around theworld, itsmost obvious lessonswere clear.Nevertheless,theNRC,bolsteredbythetaskforce’sstatementthat theU.S.nuclearfleetdidnot pose an “imminent risk” to public health and safety, ultimately elected towater down themost pressing recommendations and to slow-walk the others.JustasintheaftermathofThreeMileIsland,itappearedthattheNRCmightbepullingitspunchesinthefaceofindustryresistance.

In a July 2011 letter to the commission, Marvin Fertel, president of theNuclearEnergy Institute, had throwndown thegauntlet.While conceding that“the industry agreeswithmany of the issues identified by the task force,” hecautioned that “the task force report lacks the rigorous analysis of issues thattraditionallyaccompaniesregulatoryrequirementsproposedbytheNRC.Betterinformation from Japan and more robust analysis is necessary to ensure the

effectivenessofactionstakenbytheNRCandavoidunintendedconsequencesatAmerica’s nuclear energy facilities.” The industry appeared to be stalling—demanding further study in the belief that the passage of time would erodemomentumforregulatorychanges.Ithadcertainlyworkedinthepast.

The task force report alsoneeded topassmusterwith the rest of theNRCstaff. Although the task force members were NRC personnel, they wereoperating as an independent body outside of the usual commission peckingorder.Normally,safetyrulechangesevolvedslowlywithintheagency,workingtheirway up to the staff’s gatekeeper, the executive director for operations, apostheldbyBillBorchardt.

ButChairmanJaczkowantedthecommissiontovotedirectlywithinninetydays on the task force’s twelve recommendations, rather than on the staff’sviews of the report as filtered through Borchardt. Jaczko’s attempt to bypassseniormanagement likely grewout of the increasingly rocky relations hewashavingattheNRC,notonlywithstaffbutalsowithhisfellowcommissioners,whocouldjointooutvotehim.(Jaczkowouldeventuallyaccusethemajorityoffavoringpolicies that“loosened theagency’ssafetystandards.”)For theirpart,the other commissioners expected to also receive the staff’s opinions of thereport,perhapsbroadeningtheirunderstandingorofferingalternatives.

Borchardt and his deputy,MartyVirgilio, believed that the commissionersshouldreceivea“widerangeofstakeholderinput”beforemakinganydecisionson the task force’s recommendations. They attached a five-pagememo to thetaskforcereportmaking thissuggestion.Thememoalsoemphasized thatU.S.nuclear power plants were unlikely to experience the same problems asFukushimahad.

Jaczko reportedly disagreed with the stakeholder recommendation andbelieved that Borchardt’s attachment was improperly presented based onprocedural grounds. The chairman unilaterally intervened to remove theBorchardtattachmentbeforethetaskforcereportwasformallytransmittedtothecommissioners and toCongress.That action, among others, contributed to theinternecineconflictthatfurtherisolatedJaczkowithintheagencyandultimatelyledtohisresignationinJune2012.

Although back in July 2011 Jaczko had won the battle over the initialtransmittalof the taskforcereport, insubsequentvoteshe lost thewar.Ratherthanvotedirectlyonthetaskforce’srecommendations,themajorityorderedthestaff to first produce a series of papers analyzing the recommendations andrankingtheminpriority.Butthecommissionersmadeonedecisionimmediately:

the task force’s highest priority should become the NRC’s lowest priority.Recommendation1,torevisetheregulatoryframework,wasputatthebottomofthelist,andthestaffwasgiveneighteenmonthstocomeupwithaproposalforit.Intheinterim,thecommissionerssaid,thestaffshouldusetheNRC’sexistingregulatoryprocessestoassesstheotherrecommendations.

Fromonepointofview,thismovemadesense:itcouldtakeyearstoimposesafetyfixes if theyhad toawaitanewregulatoryframework.Buton theotherhand, imposingnew requirementsunder theold frameworkwouldonlyadd tothepatchworkofregulationsandexacerbatetheinconsistenciesidentifiedbythetaskforceaspartoftheproblem.

Given that themajorityof thecommissionersdidnotbelieveurgent safetyupgrades were needed, the necessity for speed was not their motivation forbumpingRecommendation 1 off the priority list. Rather, itwas driven by thesharedview,expressedinavotebyCommissionerWilliamOstendorff,thatthecurrentsystemwasnot“broken.”6

AfterputtingRecommendation1aside,thestaffproceededtoranktheothersin terms of priority by putting them into three tiers.Reevaluating seismic andflood hazards, addressing station blackout risks, and improving containmentventswere among theTier 1 actions that the staff believed “should be startedwithoutunnecessarydelay.”

However, the decision to proceed without first fixing the regulatoryframeworkmeantthatthenewproposalshadtonavigatealltheoldimpedimentsto improving safety. In particular, the backfit rule hung over the task forcerecommendations like the sword ofDamocles.Would theNRCbuck traditionandacknowledgethatU.S.nuclearplantswerenotadequatelyprotectedinlightof Fukushima? If not, then most of the changes recommended by the NTTFwouldbeconsidered“backfits”andwouldhavetomeettheNRC’sconvoluted“substantialsafetyenhancement”andcost-benefittests.Inthatcase,therewasagood chance that none of the recommendations would ever become arequirement.

But the old system threw up even more hurdles for change. AlthoughFukushimahadproventhatbeyond-design-basisaccidentswerearealthreat,theNRC’s obsolete guidelines still ranked them as very low-probability events,meaning that the calculated benefits of reducing the risk would also be verysmall.Andthebenefitcouldevenbezeroifthecalculationaddressedaneventthat had been left out of the risk assessmentmodels used for the cost-benefit

analyses.7

TheNRC staff ultimately sidedwith the task force and recommended thecommissionapprovethesafetyupgradesonthebasisof“assuringorredefiningthelevelofprotection...thatshouldberegardedasadequate.”Butthemajorityofthecommissionersneededmoreconvincing.Earlyon,CommissionerKristineSvinickiwarnedmembersof the task force that theywere intruding into areaswheretheycouldquicklyfindthemselves“swimminginthewatersofbackfit.”InanOctober2011vote,CommissionerOstendorffasserted that“decisionsonadequateprotectionareamongthemostsignificantpolicydecisionsentrustedtothe Commission and are not impulsive ‘go’ or ‘no-go’ choices.” This view,endorsedbythecommissionmajority,ledtoyetmoredelay.

However, in a March 2012 decision timed for the first anniversary ofFukushima, all five commissioners approved three orders imposing newregulatory requirements without the need to pass backfit tests. Although theoutcomewasunanimous,eachcommissionerhadgottentothedestinationviaadifferentcircuitousroute.Mostcontendedthattheiractionswerenotexpandingadequate protection but merely “ensuring” it. It all added up to a lot ofconfusion.But in the end, except perhaps for courts of the future thatmaybecalledontoparsethesedistinctions,itdidn’treallymakeadifference.

What didmatterwas how comprehensive and stringent the orderswere inaddressingFukushima’s lessons.Andin thoserespects, theordersfellshortonspecifics.

Part of the problem was that the commissioners had directed that therequirements be “performance based.” The concept behind performance-basedregulation is that requirements should not be too prescriptive. The regulatorshould specify thedesiredoutcomeand let theplantowner figureout thebestway to achieve it.While advocates of this approach consider itmore efficientbecause itgivesownersmoreflexibility, itactuallymakesrequirementshardertointerpretandenforce.Theindustryisfreetowriteitsownplaybook,leavingregulatorswiththeburdenoffiguringoutwhetherornotitmeetstheregulatoryintentofthesafetyrules.

Asameasureofhowpopularthisapproachiswiththenuclearindustry,overthepastcoupleofdecadestheNEIhasactuallydraftedguidancedocumentsoncomplying with performance-based regulations, which the NRC, after somenegotiation,thenapproved.

The B.5.b measures, introduced after 9/11 to help workers cope with the

aftermath of an aircraft attack, were one case in which performance-basedrequirements hadn’t worked very well. The industry argued against imposingmeasures it viewed as too prescriptive or specific, contending that thereweresimply too many potential disaster scenarios to contemplate. Through theirlobbyinggroup,plantowners insisted that theyneededmaximumflexibility tocome up with their own solutions. The NRC relented, imposing only verygeneral requirements for the B.5.b equipment and giving the industry a greatdealofleewaytodesignitsownstrategies.

However, theindustryhadnotthoughtthroughitsplanstoensurethat theywouldactuallyworkunderreal-worldconditions,suchashighradiationfields,excessiveheat,and infrastructuredamage.Thesewere theveryconditions thatcontributedtothefailureoftheJapanesesevereaccidentmanagementmeasuresat Fukushima. Yet in a vote on the Fukushima proposals, the commissionersendorsed the B.5.b process as a model for dealing with beyond-design-basisaccidents.

TwooftheNRC’sneworderswererelativelyuncontroversial.Onerequiredtheinstallationof“reliablehardenedvents”atMarkIandMarkIIboilingwaterreactorssothattheycouldbeusedunderstationblackoutconditions.Previouslyplant owners had been allowed to install these vents voluntarily, so thatNRCinspectorshadnopowertoreviewtheiradequacyorrequireimprovements.Thissituation,alegacyoftheNRC’stimidapproachtodealingwithsevereaccidentsin the 1980s, provides little confidence that vents at U.S. BWRs would haveworkedanymoreeffectivelythanthoseatFukushima.Thesecondordercalledforreliableinstrumentationinspentfuelpools,somethingthatcouldhavehelpedworkersatFukushimabetterunderstandtheunfoldingsituation.8

Thethirdorderdirectedplantstodevelop“mitigationstrategies”forbeyond-design-basisexternalevents.Butthetitlepromisedmorethantheorderactuallydelivered.Plantswererequiredtobe“capableofmitigatingasimultaneouslossofallalternatingcurrent (AC)powerand lossofnormalaccess to theultimateheat sink” for all units at a site. As the task force had recommended, thestrategieswould involve three phases: using installed equipment, usingon-siteportableequipment,andusingoff-siteequipment.Butwherethetaskforcehadrecommended that specific durations be set for the first two phases—namely,installed equipment should be able to maintain cooling for eight hours andportable equipment for the next seventy-two hours—the order did not specifyminimumdurationsforthesephases.Eachplantsitewouldproposeitsown.9

IT’SRISKYWHENINDUSTRYWRITESTHERULES

The NRC’s acquiescence to the FLEX program of rapidly deployableemergencyequipmentwastypicalofthewaytheagencyandtheindustry’sadvocacy group, theNEI, have interacted formany years in interpretingregulationsanddevelopingcompliancedocuments.

In the earlydays,whena regulationororderneeded interpreting, theNRCwoulddevelopa“regulatoryguide”andsubmititforcommentbytheaffectedindustry.Butovertimetheroleswereoftenreversed:theindustry,coordinated by NEI, would write the first drafts of guidance documentsand the NRC would comment. This shift gave the industry far greaterpowertoshapetheconceptualbasisforregulatorycompliance,leavingtheNRCtotinkeraroundtheedges.TheNEIguidancedocumentswouldthenserveasboilerplatetextforusebyallapplicantsandlicensees.

The NEI guidance for the FLEX programwas such a template. TheNRCrequiredallplantownerstosubmitplansbytheendofFebruary2013todemonstratehowtheywouldimplementtheprogramtocomplywiththemitigation strategies order. On February 28, Exelon Corporation, whichownsseventeenreactors,submitteditsplanforthePeachBottomplantinsouthcentralPennsylvania.Exelon’sproposalwas typicalofall theplantowners’ responses, closely hewing to the NEI’s guidance. It clearlydemonstratedtheshortcomingsoftheFLEXapproach.

The PeachBottom plant, situated beside the SusquehannaRiver, hastwoMark IBWRsclosely resemblingFukushimaDaiichiUnits2 and3.Exelon’s plan for dealing with a beyond-design-basis accident thereassumed from theget-go thatbatteries andelectricaldistribution systemsfor bothAC andDC powerwould be available. It assumed that off-sitepersonnelcalledtodutywouldbeabletoreachtheplantinaslittleassixhours, not necessarily a realistic assumption in the event of the type ofmajornaturaldisasterthattheemergencyplanswerebeingdesignedfor.

The Peach Bottom Atomic Power Station, located on the Susquehanna River in south-centralPennsylvania,hastwoMarkIboilingwaterreactors,similartoUnits2and3atFukushimaDaiichi.Emergency response plans for the plant depend upon many assumptions now proven to beunrealisticintheaftermathofeventsatFukushimaDaiichi.U.S.NuclearRegulatoryCommission

The plan also set time frames for coping with an extended stationblackoutthatfellshortoftheperiodsrecommendedbytheNTTF.Thetaskforcewantedplantstobeabletokeepfuelcoolforthefirsteighthoursofablackout using permanently installed equipment and thereafter usingportableequipment(suchasFLEXitems)thatwasavailableon-siteforthenext seventy-two hours. After that, one could assume that additionalequipmentandsuppliesdeliveredfromoff-sitewouldbeavailable.

For PeachBottom, Exelon estimated that the batteries needed to runcriticalequipment,includingtheRCIC,wouldlastnolongerthanfiveandahalfhours—butitalsoassertedthattheFLEXgeneratorcouldbehookedupandreadytostartrechargingthebatterieswithinfivehours.Therefore,therewasnoneedforExelontoextendthebatterycapacity.

Exelon’s plan assumed that additional backup equipment from thecloser of two Regional Response Centers, located nearly one thousandmilesawayinMemphis,wouldarriveatPeachBottomwithintwenty-fourhours.(Exeloncontendedthatitcouldkeeptheplantstableforeverwithoutany off-site assistance, with repeated torus venting, but conceded that itwouldbebettertoeventuallyhaveanalternative,lessradioactivemethod.)

Consistent with NEI’s guidance, Exelon’s plan allowed FLEXequipment tobestoredbelowflood levelon theassumption thatworkerswould have time to move it to a safer place “prior to the arrival ofpotentiallydamagingfloodlevels.”

Asquestionableasthesetimelinesare,theydon’ttakeintoaccounttheworst case. Exelon found that if a station blackout occurred duringrefueling,when theentirecoreofaunitwas in thespent fuelpool, therewouldbenotimeforthefirstcopingphaseatall:FLEXequipmentwouldhavetobesetupimmediately.Exelonassertedthatthiswasnotaproblembecauseeventhoughthepoolwouldstarttoboilaftertwoandahalfhours,thespentfuelwouldnotbecomeuncovereduntileighthourshadelapsed.

ThePeachBottomFLEXplanisaperfectexampleofthemind-setthatled to Fukushima. It represents industry and regulators scripting anaccidentwith little roomfor improvisation. Ifasingleassumptionfails—say, thatworkers don’t have time tomoveFLEXequipment to safety inadvanceofanimpendingflood—thenalltheotherbarrierswouldcollapselikedominoes.WithouttheFLEXgenerator,thebatterieswouldfailafterfiveandahalfhoursandtheRCICcouldnolongerbecountedontocoolthe reactors. Operators would eventually lose the ability to vent thecontainment and it would over-pressurize. Backup equipment, located athousand miles away in Tennessee—and possibly on the other side ofmassivefloodwatersorearthquakedestruction—probablywouldnotarriveintimetosavetheday.Nobodyapparentlythoughtthosepossibilitieswereworthconsidering,evenafterFukushimaDaiichi.

The order also specified that reactor owners must provide “reasonableprotection”oftheemergencyequipmentfromexternalevents.Butwhatdidthatmean?Thedefinitionwasapparentlyintheeyeofthebeholder.Forinstance,thetask force had said the equipment should be protected against beyond-design-basisfloods,butthecommission’sordercontainednosuchrequirement.

Inanyevent,bythetimetheNRCissuedthemitigation-strategiesorderonMarch 12, 2012, it no longer seemed to matter much. While the NRCcommissionershadbeenruminatingaboutadequateprotection,theindustrywascreatingitsownfactsontheground.PlantsiteshadalreadyorderedoracquiredmorethanthreehundredpiecesofmajorequipmentundertheFLEXvoluntaryinitiative. “Time is of the essence,” saidCharles “Chip” Pardee, then head ofpowergenerationatExelon.Arguingthattheindustryneededtomoveforwardto meet the NRC’s timeline for safety improvements that were still beingformulated, Pardee said, “We are proceeding informed by what the NRC isdoing,but[weare]outinfrontofregulations.”

The FLEX approach, however, arguably did not go nearly as far as wasneeded.For instance, the industry insisted that itspurposewas topreventcoredamage.Thus, theprogramdidnotcontemplatehowtousesuchequipment inthehighlyradioactiveandhotenvironmentthatwouldoccurafteracorestartedtomelt—eventhoughthatwasoneofthegreatestchallengesatFukushima.AndFLEX was designed with the assumption that a plant’s electrical distributionsystemswerefunctional,alsoatoddswiththerealityexperiencedatFukushima.

The industry’s eagerness to address the lessons of Fukushima even beforethe NRC could issue requirements was highly ironic at best. After all, plantownersat thesametimeweredraggingtheirfeet—sometimesfordecades—onaddressing anynumberofoutstanding safetyproblems, from fireprotection toemergencycorecoolingsystemblockages.Getting“outinfrontofregulations”withFLEXwasabrilliantmove.Themoremoneytheindustrywasspendingonequipment that met its own specifications, the more difficult—politically andpractically—itwouldbefortheNRCtorequiresubstantiallydifferentandmorerobustmeasures.

Thetacticworked.TheFLEXprogram,forallitsflaws,didnotconflictwiththe NRC’s ambiguous mitigation strategies order. After many months ofdeliberationwiththeNEIontheguidancedocumentithadpreparedfortheuseof FLEX equipment, theNRC largely endorsedNEI’s approach. The tail hadwaggedthedog.

Over the summer of 2012, the Japanese government solicited views fromcitizensas itdraftedanewenergypolicy.Theresultsweredecisive,noted thesurveyorganizers:“Wecansaywithcertaintythatamajorityofcitizenswanttoachieveasocietythatdoesnotrelyonnuclearpowergeneration.”

Although some believed that the government’s outreach was moreappearancethansubstance,thereweresignsthatthepublic’sdissatisfactionwiththeJapaneseestablishmentmightbehavinganimpactelsewhere.InSeptemberTEPCOannounced the creation of an outside review committee to oversee itsnuclear operations. With guidance from the committee, TEPCO’s newmanagementhopedtowinapprovaltorestartthesevenreactorsatKashiwazaki-Kariwa beginning in the spring of 2013, apparently confident that thegovernment’sefforttocraftanewenergypolicycurtailingnuclearpowerwouldgonowhere.

OnSeptember14,2012,theNodagovernmentunveileditsnewenergyplan,thekeystoneofwhichwastheeliminationofnucleardependencybytheendof

the2030s.Theplanwasshortonspecifics.AstheFinancialTimesnoted,itwas“asomewhatmessycompromisethatwilldelightnobody.”ItdefinitelydidnotdelightJapan’sbusinessleaders,wholobbiedtheNodagovernmenttoretainthestatus quo. “It is highly regrettable that our argument was comprehensivelydismissed,”saidtheheadofthepowerfulbusinessgroupKeidanren.10

Nodawarned thatmoving toward a nuclear-free Japanwould not be easy.“Nomatterhowdifficultitis,”hesaid,“wecannolongerputitoff.”

It tookallofaweekbeforetheenergyplanwasshotfullofsomanyholesthatitwasbarelyrecognizable.

Noda, like Kan before him, was struggling for political survival. Hispopularity ratings had not fallen quite as far as Kan’s had a year earlier, butNoda’sparty,theDemocraticPartyofJapan,hadanapprovalratingintheteens.Newelections,expectedsoon,almostcertainlywouldsweepanotherpartyandprimeministerintooffice.

Noda’senergyplanoriginallycalledforshuttingdownreactorsattheendoftheir forty-yearoperating livesandbuildingnonewones.But thedayafter itsrelease,YukioEdano,thetrademinister,saidthebanonnewconstructionwouldnot apply to three reactors already approved for construction. Even moreillogically,Japanwouldcontinuetopursueitsambitiousplantobeginfull-scaleoperationoftheRokkashoReprocessingPlant,afacilityforreprocessingspentnuclear fuel, even though presumably therewould be little reactor capacity todispose of themany tons of plutonium itwould produce each year.OperatingRokkasho would increase the massive stockpile of weapon-usable plutoniumthatJapanhadalreadyaccumulated,amajorsecurityandsafetyconcern.

It seemed that Noda, given the choice of appeasing Japan’s powerfulbusiness community or all those people “making lots of noise” on the streets,hadoptedfortheestablishment.Thebackpedalingcontinued:whenthecabinetmetonSeptember19, it sidesteppedapproving theenergyplan, sayingonly itwould “take it into consideration.” The cabinet’s failure to endorse the planmeantthatfuturegovernmentswouldnotberequiredtofollowit.ThatpromptedtheAsahiShimbuntonote,“Thegovernment’scommitmenttoabandonnuclearpowerbythe2030sisincreasinglysoundinglike‘maybe.’”

The cabinet did approve creation of a new nuclearwatchdog, theNuclearRegulationAuthority(NRA),aftermonthsofpoliticalwranglingovertheextentofitsindependence.EventhatwascastindoubtwhenitwasreportedthatmostNRAemployeeshadcomefromthewidelydiscreditedNISAandtheNSC.The

cabinet handed the new agency the unenviable task of deciding whether thenation’snuclearfleetcouldsafelyberestarted.TheNRAsaidthedecisioncouldtakemonths. The agency’s rocky start only signaled the tough job it faced inusheringinaneweraofnuclearoversight.

Themedia reported that four of six experts chargedwith drawing up newsafetyregulationsfortheNRAhadfinancialtiestothenuclearindustry.(Tryingtoput thebest faceon thatnews,anNRAspokesmannoted that themerefactthattheexpertshadtodisclosetheirpersonalfinanceswasapositivestep.)

In January 2013, the NRA issued a draft set of new safety measures thatnuclearplantswouldhavetoadoptasaprerequisiteforrestart.Theseincludedupgrades to some of the equipment that had proved inadequate at Fukushima,suchasportablepowersuppliesandwatersources,sothattheywouldbemorereliable in an extended stationblackout or other severe accident.Plantswouldhavetoshowthattheycouldmaintaincorecoolingforafullweekwithoutoff-site assistance. They would also have to install filtered vents and remotesecondarycontrol rooms. In addition, theywouldhave todemonstratedefenseagainstbothnaturaldisasters and terrorist attacks, suchas a9/11-style aircraftimpact.

The NRA then began a period of “discussion” with the utilities to obtaintheirviewsbeforefinalizingthenewrules.ThiswasunchartedterritoryinJapan.It remained tobeseen if theNRAwouldbeable tomaintain its independencewhenconfrontedwithpredictably intensepressure from theutilities toweakenthisstringentandcostlysetofproposals.

Evenas regulators inJapan’snuclearestablishmenthaggledoverdetails, thosewhose lives had been disrupted by events at Fukushima Daiichi continued tostruggle.Formanyof them, resuming theirnormal livesanytimesoonseemedunlikely.

A case in pointwere residents of the “emergency evacuation preparation”zone—aportionoftheareabetweentwelveandeighteenmilesaroundtheplant.Aboutamonthaftertheaccident,thegovernmentrecommendedthatvulnerablegroupssuchaschildrenandpregnantwomeninthiszoneevacuate,andthatallothers be ready to flee at a moment’s notice. (In contrast, the highlycontaminated area to the northwest of the plant, extending beyond eighteenmiles,was amandatory evacuation zone and remained so.)Nearly half of the58,000peopleinthe“evacuationpreparation”zonelefttheirhomes.

Whenprotectivemeasureswereliftedsixmonthslater,theevacueesstayedaway.Onlyabout3,100peoplehadreturnedasofSeptember2012.Noticeablyabsentwereyoungchildren.

Morethanayearaftertheaccident,largeareasnearFukushimaDaiichiremainedoff-limits.InvestigationCommitteeontheAccidentattheFukushimaNuclearPowerStationsofTokyoElectricPowerCompany

For residents of the town of Okuma, home to Fukushima Daiichi, theannouncement that itwouldnotbesafe to returnuntil2022was the firstblowdeliveredby thegovernment.Thencameword thatTokyoplanned tobuildasmany as nine temporary radioactive disposal facilities in Okuma—possiblebecausenoonewaslivingthere.Thatspawnedfearsthatevenwhenitwassafetogoback,noonewouldwantto.“Wehavebeenlivingtherefor1,000years,”Okuma’smayortoldareporter.

In October 2012, some of the workers who had risked their lives to wrestleFukushimaDaiichiback from thebrinkspokepubliclyabout theirexperiencesforthefirsttime.Untilthatmomentthesemenhadavoidedthelimelight.EightofthemmetwithPrimeMinisterNoda,whowasvisitingtheplant.TheybeganwithanapologytotheJapanesepeople.

Sixoftheworkersdeclinedtobeidentified,ortohavetheirfacesshownoncamera. “Many [people] view us as the perpetrators,” explained AtsufumiYoshizawa,whoworkedwith plant superintendentMasaoYoshida during theaccident.Uppermostintheirmindsastheaccidentunfolded,themensaid,wasthe safety of their fellowworkers andof nearby communities,wheremanyofthemlivedwiththeirfamilies.

They said they had never intended to abandon the plant during the crisis;they knew that erroneous reports to that effect had led to an angry exchangebetweenPrimeMinisterKan andTEPCO’s president. “I thought thatmaybe Iwouldendupnotleaving,”Yoshizawasaid,“that,asweJapanesesay,wewould‘buryourbones’inthatplace.”

Buttheworkersstayeddespitetheterrifyingconditions.“Ihadnointentionofdying,”said theoperationschief forUnits1 through4.“Everyonedid theirbest.Dyingwouldhavemeantgivingup.”

Noda returned toFukushimaPrefecture in earlyDecember, to kick off thecampaign season for the December 16 parliamentary election. Also inFukushimathatdaywasShinzoAbe,seekingreelectiontotheprimeminister’sjob that he resigned in 2007 after a troubled year in office. For voters acrossJapan,theslumpingeconomyoccupiedcenterstage,andAbepromisedchange.When the votes were counted, Abe and his conservative-leaning LiberalDemocraticPartywonbyalandslide.

Bymonth’send,AbewassworninasJapan’sseventhprimeministerinsixandahalfyears.Amonghisfirstpromiseswasavowtomoveaheadwithnew

nucleardevelopment.

12

ARAPIDLYCLOSINGWINDOWOFOPPORTUNITY

Theaccusationsbeganflyingalmost immediately.Overtheensuingweeksandmonths, everyone, it seemed,was looking for somethingor someone toblamefor the disaster at Fukushima Daiichi. Antinuclear activists around the globelookedattheaccidentandsawirredeemabletechnicalandinstitutionalfailures,reinforcing their conviction that nuclear energy is inherently unsafe. Nuclearpowersupportersindictedtheuserofthetechnology—inthisinstanceTEPCO—instead of the technology itself, and thus avoided answering larger safetyquestions.

TEPCO initially pointed fingers atMotherNature, asserting that the eventwasunavoidable.ButtheutilityalsoblamedJapanesegovernmentregulatorsfornotforcingthecompanytomeetsufficientlystringentsafetystandards.

For itspart, theJapanesegovernmentblamedthe“unprecedented”accidentonwhat itcalled“anextremelymassiveearthquakeandtsunamirarelyseeninhistory,” suggesting that there was no way authorities could have anticipatedsuch an event. By invoking forces beyond their control, TEPCO and theJapanesegovernmentabsolvedthemselvesofresponsibility.

Some experts in the United States and Japan decided the culprit was thedeficientMarkIreactordesign,contendingthatadvancedreactordesigns,suchas the Westinghouse AP1000, would not have suffered the same fate. Inresponse,theMarkI’sdesigner,GE,assertedthatnonuclearplantdesigncouldhave survived the flooding and blackout conditions that Fukushima Daiichiexperienced.

Thentherewerethosewhoarguedpreciselytheopposite:thattheFukushimadisaster was clearly preventable. The JapaneseDiet Independent Investigation

Commissionlaidblameat thefeetofbothTEPCOandJapaneseregulatorsfortheir incompetence, lack of foresight, and even corruption. The utility andgovernment should have anticipated and prepared for larger earthquakes andtsunamis, and shouldhavehadmore robust accidentmanagementmeasures inplace,thecommissionconcluded.

Itistoosimplistictosayeitherthattheaccidentwasfullypreventableorthatitwas impossible to foresee. The truth lies in between, and there is plenty ofblametogoaround.

NEWREACTORDESIGNS:SAFERORMOREOFTHESAME?

The accident at Fukushima provided nuclear advocates with a freshargument tobolster their support for constructionof anewgenerationofreactors. Certain new designs, they claimed, could have withstood acatastrophiceventsuchasthedisasteratFukushimaDaiichi.

Among those designs is theAP1000, built byWestinghouse ElectricCompany (AP stands for “advanced passive” and one thousand is itsapproximate electrical generation output in megawatts.) The reactorutilizespassive safety features to reduce theneed formachinery, suchasmotor-driven pumps, to provide coolant in the event of an accident.WestinghouseadvertisestheAP1000ascapableofwithstandingaseventy-two-hourstationblackout.SoonafterFukushima,ArisCandris,thenCEOof Westinghouse, said that the Fukushima accident “would not havehappened”hadanAP1000beenonthesite.

The design received a significant boost in February 2012 when theNRC commissioners voted 4–1 to approve licenses to construct twoAP1000 reactors at theVogtle nuclear complex, about 170miles east ofAtlanta.NRCchairmanGregoryJaczkocastthelone“no”vote,saying,“Icannotsupport issuing this licenseas ifFukushimahadneverhappened.”Jaczko anticipated that the lessons learned from the Japanese disasterwould lead the NRC to adopt new requirements for U.S. plants, and heargued that any new licenses should be conditioned on plant owners’agreementtoincorporateallsafetyupgradesthattheNRCmightrequireinthefuture.

Othernewreactordesigns,suchastheGEHitachiESBWR(“economicsimplifiedboilingwaterreactor”),alsoboastpassivesystems.Incontrast,

the French company Areva’s EPR (“evolutionary power reactor” in theUnited States, “European pressurized water reactor” elsewhere) addsredundant active safety systems and new features to cope with severeaccidents such as a “core catcher,” intended to capture and contain adamaged core if it melts through the reactor vessel. Both designs awaitNRCcertificationintheUnitedStates.

Advocatesarealsopromotingdevelopmentofsmallmodularreactors,those generating less than three hundred megawatts of electricity. Inprinciple,theunitscanbebuiltonassemblylinesandwouldallowutilitiesto augment their generating output in smaller increments to meetfluctuatingdemand.

Backers argue that because the small units could be constructedunderground, theywouldbe safer from terrorist attacksor natural eventssuchasearthquakes.Ontheotherhand,criticsarguethatinthecaseofaserious accident, emergency crews would have difficulty accessing thebelow-grade reactors, and multiple units at one site may compound thechallengesforemergencyresponseefforts,aswasseenatFukushima.

There is no question that nuclear safety can be improved throughthoughtful design of new reactors. However, nuclear power’s safetyproblems cannot be solved through good design alone. Any reactor,regardless of design, is only as robust as the standards it is required tomeet.

Unless regulators expand the spectrum of accidents that plants aredesignedtowithstand,evenenhancedsafetysystemscouldproveof littlevalue in the face of Fukushima-scale events such as an extended stationblackoutoramassiveearthquake.

InthecaseoftheAP1000,forexample,ArisCandriswaswrong.Evenif an AP1000 had been at the Fukushima site, it would have becomeendangered after three days of blackoutwhen itwould have neededACpower to refill the overhead tank that supplies the emergency coolingwater.And if theplant had experienced an earthquake larger than itwasdesignedtowithstand,thetankitselfmighthavebeenrenderedunusable.

Perhaps the strongest vote of no confidence comes from the reactorvendorsthemselves.EvenastheyheavilypromotedthenewdesignsintheUnited States, the vendors in 2003 successfully lobbied Congress toreauthorize federal liability protection for all reactors—new and old—under the Price-Anderson Act for another twenty years. While they

asserted that the next generation of plantswould pose an infinitesimallysmallrisktothepublic,theywantedtomakesuretherewouldbelimitsonthedamageclaimstheywouldhavetopayiftheywerewrong.

Thosewith an interest in advancing nuclear safety need to look past theirownbiasesandrecognizetherootcausesoftheaccident,wherevertheymaybe.Absentsuchaclear-eyedappraisal, theopportunity to identifyandcorrectpastmistakeswillbelost.Withitwillgotheopportunitytopreventthenextsevereaccident. The legacy of Fukushima Daiichi will then be revealed as a tragicfiasco.

There’s no question that TEPCO and the Japanese regulatory system bearmuchresponsibility.Eachclearlycouldhavedonemoretopreventthedisaster(like erecting a taller seawall when information about a larger tsunami threatemerged) or to lessen its severity (like equipping the plantwithmore reliablecontainmentventvalves).Suchchangecouldhavebeenaccomplished throughnewregulationsorvoluntaryinitiatives,neitherofwhichwasforthcoming.

But that is too narrow a focus. TEPCO and government regulators weremerely the Japanese affiliate of a global nuclear establishment of powercompanies, vendors, regulators, and supporters, all of whom share thecomplacentattitudethatmadeanaccidentlikeFukushimapossible.

ThesafetyphilosophyandregulatoryprocessthatgovernedFukushimawerenotfundamentallydifferentfromthosethatexistelsewhere,includingtheUnitedStates. The reactor technology was nearly identical. The reality is that anynuclear plant facing conditions as far beyond its design basis as those atFukushimawould be likely to suffer an equivalent fate. The story linewoulddiffer, but the outcome would be much the same—wrecked reactors, off-siteradioactivecontamination,socialdisruption,andmassiveeconomiccost.

The catastrophe at Fukushima should not have been a surprise to anyonefamiliar with the vulnerabilities of today’s global reactor fleet. If thosevulnerabilitiesarenotaddressed,thenextaccidentwon’tbeasurprise,either.

Fukushima triggered extensive “lessons learned” reviews in Japan,France, theUnited States, and elsewhere.Many lessons have indeed been learned, but todate fewhavebeenpromptlyandadequatelyaddressed—at least in theUnitedStates.Thereason,ofcourse,istheprevailingmind-set.

“ItCan’tHappenHere”That mind-set underlies all that went wrong at Fukushima Daiichi. Whilenumerous technological and regulatory failures contributed to the events thatbeganonMarch11,2011, thatpervasivebelief standsas the rootcauseof theaccident.

In the United States, “it can’t happen here” was a common refrain whiledetails of the Fukushima accident were still unfolding. In June 2011, forexample,SenatorAlFranken joked that “the chancesof an earthquakeof thatlevel inMinnesota are very low, but ifwe had a tsunami inMinnesota,we’dhavebiggerproblemsthaneventhereactor.”

SenatorFranken’scasualattitude illustrates theproblem.Yes, it isunlikelythatatsunamiwillsweepintothenorthernplains.Butseriouspotentialthreatstoreactorsdoexistinhishomestate,aswellasthestatesofmanyothermembersofCongress.

Twopressurized-waterreactorsatthePrairieIslandnuclearplant,southeastofMinneapolis, are among the thirty-four reactors at twenty sites around theUnited States downstream from large dams. A dam failure could rapidlyinundateanuclearplant,disabling itspowersuppliesandcoolingsystems,notunliketheimpactofatsunami.1

NorisadamfailuretheonlytypeofaccidentthatcouldcreateFukushima-scale challenges at aU.S. nuclear plant. Fire is another.A fire could damageelectriccablingandcircuitboards, cuttingoffelectricity frommultiplebackupsafetysystemsas floodingdidatFukushima.TheNRCadoptedfire-protectionregulations in1980followingaveryseriousfire inMarch1975at theBrownsFerrynuclearplantinAlabama.Aworkerusingalitcandletocheckforairleaksaccidentallystartedafireinaspacebelowthecontrolroom.ThefiredamagedelectricalcablesthatdisabledalloftheemergencycorecoolingsystemsfortheUnit 1 reactor andmost of those systems for the Unit 2 reactor. Only heroicactionsbyworkerspreventeddualmeltdownsthatdayatBrownsFerry.

Thethreatoffiresremainsamajorcontributortotheriskofcoredamageatnuclearplants.Decadeslater,firesafetyregulationsimposedbytheNRCinthewakeofBrownsFerryhavenotbeenmetatroughlyhalfthereactorsoperatingintheUnitedStates—includingthethreereactorsatBrownsFerry.

So, lesson one: “It can happen here.”And that reality leads directly, onceagain,tothemostcriticalquestion.

“HowSafeIsSafeEnough?”Fukushimaandothernuclearplantsarenothousesofcardswaitingforthefirstgustofwindorground tremor to collapse.Theyaregenerally robust facilitiesthat require many things to go wrong before disaster occurs. Over the years,manythingshave,mostlywithoutseriousconsequences.

Keytosafetyatanuclearplantaremultiplebarriersengineeredtoprotectthepublic from radiation releases—the so-called defense-in-depth approach. Eachbarrier should be independent of the others and provide a safety marginexceeding the worst conditions it might have to endure in any accidentenvisionedinthedesignbasisoftheplant.Regulatorsregarddefense-in-depthasahedgeagainstuncertaintyintheperformanceofanyonebarrier.

The design and operation of the damaged reactors at Fukushima Daiichiwereconsistentwiththedefense-in-depthprincipleascommonlyappliedaroundtheworld.Multipleanddiversecooling systemsexisted to forestalldamage tothe reactor cores. When cooling was interrupted and core damage did occur,leak-tight containment buildings limited the escape of radioactivity. Whencontainments leaked and a large amount of radioactivity escaped, emergencyplanswereinvokedtoevacuateorshelterpeople.

U.S.NuclearRegulatoryCommission

Defense-in-depthworkswell—asfarasitgoes.Theconcepthassucceeded

in limiting the frequency of nuclear disasters. Since the 1970s, three nuclearplant accidents have drawn international attention: ThreeMile Island in 1979,Chernobyl in 1986, andFukushima in 2011.Were it not for defense-in-depth,thelistcouldbelarger.

HurricaneAndrew,whichpummeledFlorida in1992,extensivelydamagedthe Turkey Point nuclear plant near Miami, but defense-in-depth preventeddisaster.Theplantlostaccesstoitsoff-siteelectricpowergridforseveraldays,butemergencydieselgeneratorspoweredessentialequipmentinthemeantime.And while winds knocked over a water tower and extensively damaged awarehouseand trainingbuildingonsite,morerobuststructuresprotectedotherwatersuppliesandessentialequipment.

AmonthafterFukushima,asevere tornadodisconnectedtheBrownsFerryplant from the electrical grid. That June, the Fort Calhoun nuclear plant inNebraska experienced flooding that temporarily made it an island in theMissouri River, and in August the North Anna nuclear plant in Virginia wasshakenbyanearthquakeoflargermagnitudethanitwasdesignedtowithstand.In each case, the conditions caused by the accident did not exceed the safetymarginstofailure—fromalossofoff-sitepoweratBrownsFerry,afloodatFortCalhoun,oranearthquakeatNorthAnna.

Butdidtheseeventsprovetheinherentsafetyofnuclearplants,astheU.S.industryand regulators claim?Ordid theyconstitute accidents avoidednotbygoodforesight,butratherbygoodfortune?

For all its virtues, defense-in-depth has an Achilles’ heel, one rarelymentioned in safety pep talks. It is known as the common-mode failure. Thathappenswhenasingleeventresultsinconditionsexceedingthesafetymarginsofallthedefense-in-depthbarriers,cuttingthroughthemlikeahatchetthroughalayercake.

Common-modefailure iswhatfloodingcausedatFukushimaandwhatfirecaused at Browns Ferry. Flooding or fire took out all the redundant systemsneeded tocool the reactor cores, the systemsneeded tokeep thecontainmentsfromoverheatingand leaking,and the systemsneeded tohelppredict thepathand extent of the radioactive plumes. At Browns Ferry, workers managed toemployadhocmeasuresintimetopreventdisaster.AtFukushima,timeranout.

Defense-in-depthisbothablessingandacurse.Itallowsmanythingstogowrongbeforeanuclearplantdisasteroccurs.Butwhentoomanyproblemsariseoracommon-modefailuredisablesmanysystems,defense-in-depthcan topplelike a row of dominoes. The risk of common-mode failure can be reduced

throughenhancingdefense-in-depth,butitcanneverbeeliminated.The truecurseofdefense-in-depth is that ithas fosteredcomplacency.The

existenceofmultiplelayersofdefensehasexcusedinattentiontoweaknessesineachindividuallayer,increasingthevulnerabilitytocommon-modefailure.

Fukushima Daiichi was a well-defended nuclear plant by accepted standards,with robust, redundant layers of protection.When the earthquake knockedoutthe off-site electrical grid, emergency diesel generators stood ready as thebackup power source. Each of the six reactor units had at least two of thesegenerators(oneunithadthree).Asingleemergencygeneratorcouldprovideallthe power needed for cooling a core and other essential tasks, but defense-in-depthmadesureeveryreactorhadatleastonespare.

Itdidn’thelp.Thegeneratorswereprotected,likethereactorsthemselves,bytheseawallerectedalongthecoast.Whenthetsunamiwashedovertheseawall,it disabled all but one of the emergency generators or their electricalconnections.

Evenwithout the generators, defense-in-depth offeredprotection.Banks ofbatteries were ready to power a minimal subset of safety equipment whiledamage to theACpower systemswas being repaired. The battery capacity atFukushimawaseighthoursperunit, assumed tobeample time forworkers toeitherrestoreanemergencydieselgeneratororrecovertheelectricalgrid.Butittook nine days to partially reconnect the plant to the grid and even longer torestorethegenerators.

AtFukushima,asintheUnitedStatesandelsewhere,reactoroperatorsweretrained in emergency procedures for responding to severe accidents. Theseproceduresinstructedthemtotakestepslikeventingthecontainmenttoreducedangerously high pressure and enable coolingwater to enter.But themanualsdid not envision the conditions the operators actually faced—for example, theneed to operate vents manually in darkness—and thus workers could notimplementtheseproceduresintimetopreventthemeltdowns.

The last defense-in-depth barrier was evacuation. But at Fukushima,emergencyplanningprovedineffectiveatprotectingthepublic.Evacuationareashad to be repeatedly expanded in an ad hoc manner, and in some cases thedecisions were made far too late to prevent radiation exposures to manyevacuees.

AllofFukushima’sdefensivebarriersfailedforthesamereason.Eachhada

limit thatprovidedtoolittlesafetymargintoavertfailure.Hadjustonebarrierremained intact, the plant might well have successfully endured the one-twopunch from the earthquake and tsunami or at the bare minimum, the publicwouldhavebeenprotectedfromtheworstradiationeffects.

Thechancethatallthebarriersmightfallwasneverpartoftheplanning.Ineffect,thenuclearestablishmentwasridingacarousel,confidentthatthepassingsceneryofanticipatedincidentswouldneverchange.Lostintheprocesswasthisreality: the brass ring for this not-so-merry-go-round involves both foreseeinghazards and developing independent, robust defense-in-depth barriers toaccommodate unforeseen hazards. One without the other has been repeatedlyshown,attremendouscost,tobeinsufficient.

SevereaccidentslikeFukushimarenderthestatusquountenableforthenuclearestablishment. Something has to change. But meaningful change—a truereduction inpotentialdanger to thepublic—willnotoccuruntil regulatorsandindustry lookaheadand to the sides, atwhatcouldhappen,not solelyatwhathashappened.

But such an approachwould be a turnabout for the nuclear establishment.Historically,whenrespondingtoeventslikeThreeMileIsland,theindustryandregulators have worked hard to narrow the scope of the response, simplypatchingholesintheexistingsafetynetratherthanaskingwhetherabetternetisneeded.Toputitbluntly,unlessthisprocessisradicallyoverhauled,itwilltakemanymorenucleardisastersandmanymoreinnocentvictimstomakethesafetynetasstrongasitshouldbetoday.

Highwaydepartmentscouldputuproadsidesignssaying“Don’tGoTooFast”or“DriveataReasonablePace.”Instead,theyputupsignsreading,forexample,“SpeedLimit 55”or “MaximumSpeed20” so that driversunderstandwhat isexpectedand lawenforcementofficersknowwhen to issue traffic tickets.Theformersignswouldconstituteentirelyuselessmeasures:acarwrappedaroundatreemust have been traveling too fast, but another barreling through a schoolzoneat120milesperhourmustbeoperatingatareasonablespeedifitdoesn’tstrikeanychildren.Safetyrequiresspecificity.Lackofspecificityinvitesafree-for-all.

SuchispreciselywhattheNRC’sNear-TermTaskForcetriedtoavoidinitsproposals for reducingvulnerabilitiesatU.S.nuclearplants.TheNTTFstarted

itsreportwitharecommendationforfundamentalchange.ItcalledontheNRCto redefine its historical safety threshold of “adequate protection,” this timeestablishing a clear foundation to guide both regulators and plant owners inaddressingbeyond-design-basisaccidents.

In essence, the NTTF’s first recommendation urged the NRC to formallyrecognize that beyond-design-basis accidents need to be guarded against withunambiguous requirements based on robust defense-in-depth and well-definedsafety margins. In this way, plant owners as well as NRC reviewers andinspectors would better be able to agree on what was acceptable. Inspectorswouldhavealegalbasisfordeclaringviolationsshouldplantownersfailtomeettherequirements;atthesametime,plantownerswouldbebetterprotectedfromarbitraryrulings.

TheNTTF did not propose taking a sledgehammer to the existing system.Insteaditrecommendedcreatinganewcategoryofaccidentscenariostocoverarange of possibilities not envisioned in the design bases of existing nuclearplants. This new category of “extended design-basis accidents” could includeaspectsofsomeoftheextremeconditionsexperiencedatFukushima.Anewsetofregulationswouldbecreatedforextendeddesign-basisaccidents,eliminatingthe “patchwork” that currently governed beyond-design-basis accidents.However, the requirements themselves would be less stringent than those fordesign-basisaccidents.

ThetaskforcebelievedthattheNRChadcometodependtoomuchontheresultsofhighlyuncertainriskcalculationsthatreinforcedthebeliefthatsevereaccidents were very unlikely. That, in turn, had provided the NRC with arationaletoshrinksafetymarginsandweakendefense-in-depth.Toremedytheproblem, the task force requested that the commission formally consider “thecompletenessandeffectivenessofeachlevelofdefense-in-depth”asanessentialelementofadequateprotection.ThetaskforcealsowantedtheNRCtoreduceitsreliance on industry voluntary initiatives, which were largely outside ofregulatorycontrol,andinsteaddevelopitsown“strongprogramfordealingwiththeunexpected,includingsevereaccidents.”

The task force members believed that once the first proposal wasimplemented,establishingawell-definedframeworkfordecisionmaking, theirotherrecommendationswouldfallneatlyintoplace.Absentthatimplementation,each recommendation would become bogged down as equipment qualityspecifications,maintenancerequirements,andtrainingprotocolsgothashedoutonacase-by-casebasis.

But when themajority of the commissioners directed the staff in 2011 topostpone addressing the first recommendation and focus on the remainingrecommendations,thegamewaslostevenbeforetheopeningkickoff.

TheNTTF’sRecommendation1wasakintothesevereaccidentrulemakingeffortscuttlednearlythreedecadesearlier,whentheNRCconsideredexpandingthe scopeof its regulations to addressbeyond-designaccidents.Then, asnow,theperceivedneedforregulatory“discipline,”aswellasindustryoppositiontoan expansion of theNRC’s enforcement powers, limited the scope of reform.The commission seemed to be ignoring amajor lesson of FukushimaDaiichi:namely, that the“fightingthelastwar”approachtakenafterThreeMileIslandwassimplynotgoodenough.

Consider theorder formitigation strategies issuedby theNRC to all plantownersonMarch12,2012,ayearandadayafterFukushima.Onepartof theorder required that plant owners “provide reasonable protection for theassociated equipment from external events” like tornadoes, hurricanes,earthquakes, and floods. “Full compliance shall include procedures, guidance,training, and acquisition, staging, or installing of equipment needed for thestrategies,”theorderread.

But what is “reasonable protection”? What kind of “guidance” would beadequate,andhowrigorouswouldbethetrainingbe?TheNTTF’sfirstproposalwould have required specific definitions. Now, without a concrete standard,NRC inspectors will be ill equipped to challenge protection levels they deemunreasonable. Conversely, plant owners will be defenseless against pressurefromtheNRCtoprovidemore“reasonable”levelsofprotection.2

A second example: another order the NRC issued on March 12, 2012,requiredtheownersofboilingwaterreactorswithMarkIandIIcontainmentstoinstallreliablehardenedcontainmentvents.Theyleftforanotherdayadecisiononwhethertheradioactivegasfromcontainmentshouldbefilteredbeforebeingventedtotheatmosphere.

Such vents are primarily intended to be used before core damage occurs,when the gas in the containment would not be highly radioactive and filterswouldnotnormallybeneeded.However,asFukushimamadeclear,itispossiblethat the ventswill have to be usedafter core damage occurs, to keep it fromgetting worse. In that case, filters could be crucial to reduce the amount ofradioactivityreleased.Thepresenceoffilterscouldalsomakeventingdecisionslessstressfulforoperatorsintheeventthattheyweren’tsurewhetherornotcore

damagewastakingplace.InNovember2012,theNRCstaffrecommendedthatfiltersbeinstalledintheventpipes,primarilyasadefense-in-depthmeasure.

Butwhatmightseemasimple,logicaldecision—installa$15millionfiltertoreducethechanceoftensofbillionsofdollars’worthoflandcontaminationaswellasharmtothepublic—gotcomplicated.ThenuclearindustrylaunchedacampaigntopersuadetheNRCcommissionersthatfiltersweren’tnecessary.Akey part of the industry’s argument was that plant owners could reduceradioactivereleasesmoreeffectivelybyusingFLEXequipment.

Vent filters would only work, the argument went, if the containmentremainedintact.Ifthecontainmentfailed,radioactivereleaseswouldbypassthefilters anyway. And sophisticated FLEX cooling strategies could keepradioactivity inside the containment in the first place. Further, the absence offiltersatFukushimamightnothavecausedthewidespreadlandcontaminationinanyeventbecause itwasn’tclear that the largest releasesoccurred through thevents;theradioactivitymayhaveescapedanotherway.

The NRC staff countered by claiming that the FLEX strategies were toocomplicatedtorelyon:theyrestedontoomanyassumptionsaboutwhatmightbetakingplacewithinareactorincrisisandwhatoperatorswouldbecapableofdoing.Incontrast,apassivefiltercouldbecountedonundermostcircumstancesto do its job—filter any radioactivity that passed through the vent pipes. Thestaffarguedthatfilterswouldbewarrantedasadefense-in-depthmeasure.Thestaff also pointed out thatmanyother countries, likeSweden, simply requiredventfilterstobeinstalleddecadesagoasaprudentstep.

Withoutanexplicit requirement toconsiderdefense-in-depth, as theNTTFhad called for in its first recommendation, theNRC commissioners could feelfree to reject the staff’s arguments. InMarch2013, theyvoted 3–2 to delay arequirement that filters be installed, and recommended that the staff considerother alternatives to prevent the release of radiation during an accident.However, at the same time the commissioners voted to require that the ventsthemselves be upgraded to be functional in a severe accident. This seconddecisiondidn’tmakemuchsense:ifthecommissionersbelievedtheventsmightbe needed in a severe accident, then what excuse could there be for notequippingthemwithfilters?

As the Fukushima disaster recedes in publicmemory, and theNRC sendsmixed signals, the nuclear establishment has begun relying on the FLEXprogramtoaddressmoreandmoreofthesevereaccidentsafetyissuesidentifiedbythetaskforceandtheNRCstaff.IthascometoseeFLEXnotasashort-term

measurebutasanenduringsolution—allthatisneededtopatchanyholesinthesafetynet.

Threemonths before the vote on the filters, the commissioners decided toslow down the development of a new station blackout rule—one they hadoriginally identifiedasapriority. Inpart, itwasbecauseof theirconfidence inFLEX.TheNRClaternotifiedCongress that ithadrejectedanumberofothersafety proposals, such as adding “multiple anddiverse instruments tomeasure[plant] parameters” and requiring all plants to “install dedicated bunkers withindependent power supplies and cooling systems,” because it believed thatFLEXwassufficient.ButitisunclearhowFLEXwouldobviateeithertheneedfor additional reliable instrumentation or the desirability of a bunkeredemergency cooling system. Indeed, both measures would support FLEXcapabilitiesshouldacrisisoccur.

Despite the willingness of the NRC to give FLEX a resounding vote ofconfidence,therewerethreeimportantdefense-in-depthissuesthatcouldnotbedismissedwithawaveoftheFLEXmagicwand.TheseissueshadbeenflaggedbytheNRCstaffpost-Fukushimaasissuesthatwereofgreatpublicconcernanddeservedconsideration.

The first related to theU.S.practiceofdenselypackingspent fuelpools,asituation that some critics had long pointed to as a safety hazard and that theNRChadlongcounteredwasperfectlysafe.

IntheaftermathofFukushima,itturnedoutthattheUnit4spentfuelpool—the subject of somuch alarm during the crisis—had escaped damage after all(see theappendixformoreon this).Thatfindingallowedsomein the industryand the NRC to contend that concerns about spent fuel pool risks wereunfounded.Theirclaimsdidnot take intoaccount the fact thatU.S. spent fuelpools typicallycontainseveral timesasmuchfuelasUnit4did,and thereforecouldexperiencedamagemuchmorequicklyintheeventoflossofcoolingoracatastrophic rupture. The industry argued in turn that FLEX was designed toprovideemergencycoolingofspentfuelpools.Butthatwouldrequireoperatoractions at a time when attention would likely be torn by other exigencies, ashappenedatFukushima.

Acceleratingthetransferofspentfueltodrycaskswouldenhancesafetybypassivemeans.TheNRCpledgedtolookatthisissueagain,butitwasaccordedalowpriority.

The second and third issues related to emergency planning zones and todistributionof potassium iodide tablets to the public to reduce the threat from

radioactive iodine.Fukushimademonstrated thata severeaccidentcouldcauseradiation exposures of concern to people as far as twenty-fivemiles from therelease site. Indeed, the worst-case projections of both the Japanese and U.S.governments found that evenTokyo,more than one hundredmiles away,wassimilarlythreatened.

Nonetheless, the NRC continued to defend the adequacy of a ten-mileplanningzoneforemergencymeasuressuchasevacuationandpotassiumiodidedistribution.Theagencyarguedthatevacuationzonescouldalwaysbeexpandedifnecessaryduringanemergency—apositionhard to reconcilewith the likelydifficulty of achieving orderly evacuations of people who had not previouslyknowntheymightneedtofleefromanuclearplantaccidentoneday.(Proddedinto action by a petition from an activist group, the Nuclear Information andResource Service, the NRC agreed to look into the emergency planningquestion,butitisonaveryslowtrack.)

Onefinalissuetoconsideristheriskoflandcontamination,somethingthatcouldbeanenormousproblemevenifallevacuationmeasuresweresuccessful.InthepasttheNRChasassessedpotentialaccidentconsequencessolelyintermsof early fatalities and latent cancer deaths, but Fukushima showed thatwidespreadlandcontamination,andtheeconomicandsocialupheavalitcreates,mustalsobecounted.3

The NRC staff proposed to the commissioners that the NRC address thisissue in revising its guidelines for calculating cost-benefit analyses, but thecommissionersdidnotshowmuchinterest.It,too,appearstobeonaslowtrack.

As for the fateof theNTTF’sRecommendation1—revising the regulatoryframework? That seems to have slipped not only off the front burner butpossibly off the stove. In February 2013, the NRC staff failed to meet thecommissioner’sdeadlineforaproposalrelatedtotherecommendationandaskedfor more time. As of this writing, Recommendation 1 continues to fade as apriority,withtheNRCstaffcontendingthat“itisacceptable,fromthestandpointofsafety,tomaintaintheexistingregulatoryprocesses,policyandframework.”

Safety IOUs are worse than worthless. They represent vulnerabilities atoperatingnuclearplantsthattheNRCknowstoexistbutthathavenotyetbeenfixed.Theyare,simplyput,disasterswaitingtohappen.

The NRC’s practice of identifying a safety problem and accepting a non-solutioncontinues.Thepost-Fukushimaproposalsarejustthelatestexample—

albeitthemostworrisome.Severe reactor accidents will continue to happen as long as the nuclear

establishmentpretendstheywon’thappen.Thatthinkingmakesluckoneofthedefense-in-depth barriers. Until the NRC acknowledges the real possibility ofsevere accidents, and begins to take corrective actions, the public will beprotectedonlytotheextentthatluckholdsout.

Of course trade-offs are inevitable. It would be ideal if every defense-in-depthbarrierwerefullyandindependentlyprotectiveagainstknownhazards,butrealistically that price tagwould likely be prohibitive. The nuclear industry isquicktoopposenewsafetyrulesonthebasisofcost,whichishardlysurprisinggiventheconcernsofshareholdersaswellasratepayers.

On the other hand, onemust consider the price tag, in both economic andhuman terms, of an accident like Fukushima. Ask TEPCO’s shareowners—aswell as the Japanese public—today what they would have paid to avoid thataccident.

Sohowsafeissafeenough?Inthatcriticaldecision,thepublichaslargelybeenshut out of the discussion. This is true in the United States, in Japan, andeverywhere else nuclear plants are in operation. Nuclear development,expansion,andoversighthavelargelyoccurredbehindacurtain.

Nuclear technology is extremely complex. Its advocates, in their zeal topromotethattechnology,haveglossedoverunknownsanduncertainties,thrownupascreenofarcaneterminology,andsetsafetystandardswithunquantifiablethresholdssuchas“adequateprotection.”Intheprocess,thenuclearindustryhascometobelieveitsownstory.

Regulators too often have come to believe that there is a firmer technicalbasisfortheirdecisionsthanactuallyexists.Officials,inparticular,mustgrapplewithoverseeinga technology that few thoroughlyunderstand, especiallywhenthingsgowrong.Fukushimademonstratedthat.

Meanwhile, average citizens have been lulled into believing that nuclearpower plants are safe neighbors, needing no attention or concern because theownersareresponsibleandtheregulatorsarethorough.Yetitisthosecitizens’health,livelihoods,homes,andpropertythatmaybepermanentlyjeopardizedbythefailureofthisflawedsystem.

Thepublicneedstobefullyinformedofuncertainties,ofrisksandbenefits,and of the trade-offs involved. Scientists and policy makers must be candid

aboutwhattheyknow—anddon’tknow;aboutwhattheycanhonestlypromise—and can’t promise.And once full disclosures aremade, the peoplemust begiven the final voice in setting policy. They must be the arbiters of what isacceptableandhowthegovernmentactstoensuretheirprotection.

What that decision-making process will look like is unclear. One thing iscertain:we’renowhereclosetoitnow.

This chapter has focused on two questions inspired by Fukushima: who is toblamefortheaccidentandwhatcanbedonetopreventthenextone?Bynowitshouldbeclear that theentirenuclearestablishment is responsible, rather thanjust TEPCO and its regulators. Even if indicted, however, the nuclearestablishmentlikelycouldnotbeconvicted.Foritissheerinsanitytokeepdoingthesamethingoverandoverhopingthattheoutcomewillbedifferentthenexttime.

What is needed is a new, commonsense approach to safety, one thatrealisticallyweighsrisksandcounterbalancesthemwithproven,nottheoretical,safetyrequirements.TheNRCmustprotectagainstsevereaccidents,notmerelypretendtheycannotoccur.

How can that best be achieved? First, the NRC needs to conduct acomprehensive safety reviewwith the blinders off. Thatmust take placewithwhat formerNRCCommissionerPeterBradfordcalls regulatory“skepticism.”The commission staff—and the five commissioners—should stopworrying somuchaboutmaintaining regulatory“discipline”and startworryingmoreaboutthe regulatory tunnel vision that could cause important risks to be missed ordismissed.

Thatsafetyreviewmustcomeintheformofhands-on,real-timeregulatoryoversight.EveryplantintheUnitedStatesshouldundergothekindofin-depthexaminationofsevereaccidentvulnerabilitiesthattheNRCcontemplatedinthe1980sbutfellshortofimplementing.

Thefirst step isadoptionofa technicallysoundanalysismethod that takesintoaccount thedeficienciesinriskassessmentthatcriticshavenotedoverthedecades,particularlythefailuretofullyfactorinuncertainty.Issuesthatarenotwell understood need to be included in error estimates, not simply ignored.Settingthesafetybaratxmustcarrytheassociatedpolicyquestion“Whatifxplus1happens?”

Fortunately,theNRCdoesnothavetostartfromscratchtodoasoundsafety

analysis.Eachnuclearplant thathasapplied fora twenty-year license renewalfrom the NRC—around 75 percent of all U.S. plants—has conducted a studycalleda“severeaccidentmitigationalternatives”(SAMA)analysisaspartoftheenvironmentalreviewrequiredundertheNationalEnvironmentalPolicyAct.

ASAFETYFRAMEWORKREADYFORACTION

A SAMA analysis entails identifying and evaluating hardware andprocedure modifications that have the potential to reduce the risk fromsevereaccidents,thendeterminingwhetherthevalueofthesafetybenefitsjustifiestheircost.

Oddly enough, even though the plant owners and the NRC haveidentified dozens of measures that would pass this cost-benefit test andthus might be prudent investments, none have had to be implementedunder the law. That’s because theNRC has thrown into the equation itscontortedbackfitrule.Therulemeansthatfor thechangestoberequiredthey alsomust represent a “substantial safety enhancement”—a standardveryhardtomeetgiventhelowriskestimatesgeneratedbytheindustry’scalculations.

Thus, theSAMAprocesshasbeenmerely an academic exercise.ButtheupgradesidentifiedintheSAMAanalysesprovideacomprehensivelistofchangesthatcouldreducesevereaccidentriskateachplant.

TheSAMAchanges are a starting point. They should be reevaluatedunderanewframework,onethatbetteraccountsforuncertaintiesandthelimitationsofcomputermodels,improvesthemethodologyforcalculatingcostsandbenefits,andallowsthepublictohaveasayintheanswertothequestion“Howsafeissafeenough?”Thisprocesswouldproduceaguidefor plant upgrades that could fundamentally improve safety of the entirereactorfleetandprovidethepublicwithayardstickbywhichtomeasureperformance.

Another toolforassessingsevereaccidentriskswouldbeastress testprogram—ananalysis of howeachplantwould farewhen subjected to avariety of realistic natural disasters and other accident initiators. (As forindustry’s much-touted but untested FLEX “fixes,” they could be takenintoaccount,buttheirlimitationsandvulnerabilitieswouldbefairgameinanyanalysis.)

Before the testing process begins, another change is essential: thepublic,nottheindustry,mustfirstdeterminewhatisapassinggrade.

These SAMA analyses represent an unvarnished checklist of the changesneededat eachnuclearplant in theUnitedStates todrivedown the riskof anAmerican Fukushima. Using that information as a roadmap for enhancedregulationandoperationsisnot theentireanswer,but it isafirststepinbetterunderstandingtherisksofnuclearpowerandhowtocontrolthem.

Once the question “How safe is safe enough?” is answered, a secondquestion must be asked and resolved, again with input from the public. Thatquestionis:“Howmuchproofisenough”?

Inotherwords, howbest toprove that industry and regulators are actuallycomplyingwiththenewrules,bothinletterandinspirit?TheNRC’sregulatoryprocessisamongthemostconvolutedandopaque;justasinJapan,publictrusthassufferedasaresult.

Intheend,theNRCmustbeabletotelltheAmericanpublic,“We’vetakeneveryreasonablesteptoprotectyou.”Anditmustbethepublic,notindustryorbureaucrats,whodefine“reasonable.”

As Japan was marking the second anniversary of the Fukushima Daiichiaccident, the NRC held its annual Regulatory Information Conference, thetwenty-fifth, once again attracting a large domestic and international crowdofregulators,industryrepresentatives,andothers.

Duringthetwo-daysession,manypresentationsweredevotedtothelessonslearned from Fukushima, including technical discussions about core damage,floodingandseismicrisks,andregulatoryreforms.Butbynowitwasapparentthat littlesentimentexistedwithin theNRCformajorchanges, includingthoseurgedbythecommission’sownNear-TermTaskForcetoexpandtherealmof“adequateprotection.”TheNRCwasbacktobusinessasusual,focusedonsmallholes in the safety net, ignoring the fundamental lesson of Fukushima: Thisaccident should have been no surprise, and without wholesale regulatory andsafetychanges,anotherwaslikely.

Oneofthefinaleventsoftheconferencewasapaneldiscussionfeaturingtheagency’s four regional administrators and two nuclear industry officials, whofieldedquestionsfromanaudienceofothernuclearinsiders.Thesubjectsranged

fromdealingwiththepublicinthepost-FukushimaeratotheaddedworkloadofinspectorsatU.S.reactors.Themoodwasupbeat,thegive-and-takefriendly.

But amid the camaraderie, one member of the panel seemed impatient todeliveramessagetotheaudience.Whenitcametoaddressingtheoverarchinglessons of Fukushima—for regulators and industry people alike—he broughtunique credentials to the task.The speakerwas theNRC’s ownChuckCasto,whohadarrivedinJapaninthefirstchaoticdaysoftheaccidentandremainedthereforalmostayearasanadvisor.

Now, as the conferencewound to a close, Castowas eager to offer somewordsof advice.Thepublicdoesnot understand theNRC’sunderlying safetyphilosophy of “adequate protection,” he cautioned. “They want to see uschargingouttheremakingthingssaferandsafer,tobepro-safety.Ifthisdegreeissafe,alittlebitmoreismoresafe,”hetoldtheaudience.

Ashort time later,hisvoicefillingwithemotion,Castospokeof thebraveoperatorsatFukushima,whomhecalled“anincrediblesetofheroes.”

“This industry over its fifty-some years has had a lot of heroes,” hecontinued. He spoke about Browns Ferry, ThreeMile Island, and Chernobyl.Those andother events,Casto told his audience,make theway forward clear.“Wehonorandwerespecttheheroesthatwe’vehadinthisindustryoverfiftyyears—butwedon’twantanymore.

“Wehave to have processes and procedures and equipment and regulatorsthat don’t put people in a position where they have to take heroic action toprotectthehealthandsafetyofthepublic,”Castosaid.“Whatwereallyhavetoworkonisnomoreheroes.”

APPENDIX

THEFUKUSHIMAPOSTMORTEM:WHATHAPPENED?

AccidentmodelersfromTEPCO,theU.S.nationallaboratories,industrygroups,and other organizations gathered in November 2012 at a meeting of theAmerican Nuclear Society (ANS) to present the results of their attempts tosimulatetheeventsatFukushimaandreproducewhatwasknownaboutthem.

Like any postmortem, the goal was to glean asmany answers as possibleabout the causes of the events at Fukushima Daiichi. But answers provedtroublinglyelusive.

Oneofthefirstdifficultiesencounteredbytheanalystswasthelackofgoodinformationabouttheprogressionoftheaccidents.Thedamagedreactorswerestill black boxes, far too dangerous for humans to enter, much less conductcomprehensive surveys of, and reliable data on their conditionwas sparse. Insome cases, analysts had to fine-tune their models using trial and error,essentiallyplayingguessinggamesaboutwhatexactlyhadhappenedwithinthereactors.

Evenso,thecomputersimulationscouldnotreproducenumerousimportantaspects of the accidents. And in many cases, different computer codes gavedifferent results.Sometimes thesamecodegavedifferent resultsdependingonwhowasusingit.

The inabilityof thesestate-of-the-artmodelingcodes toexplainevensomeof the basic elements of the accident revealed their inherentweaknesses—andthehazardsofputtingtoomuchfaithinthem.

Sometimesmodelerswerefrustratedbyalackofessentialdata.Forexample,when water-level measurements inside the three reactors were available, theywereusuallywrong.Thereadings indicatedthatwater levelswerestablewhen

they were actually dropping below the bottom of the fuel. This happenedbecause thegaugeswerenotcalibrated toaccount for theextreme temperatureandpressureconditionsthatwereoccurring.Althoughtheproblemshouldhavebeen obvious at the time, TEPCO didn’t question the erroneous data andpubliclyreleasedit.

ThelackofreliablewaterlevelsmeantthatanalystsinJapanandelsewherereally did not know then or now how much makeup water was entering thereactorvesselsatwhattimesduringtheaccident,acriticalpieceofinformationfor understanding the effectiveness of emergency water-injection strategies.Differentassumptionsfor“correcting”thisunreliabledatayieldedsignificantlydifferentresults.

At the ANS meeting, researchers from Sandia National Laboratoriespresented results they obtained using the computer code called MELCOR,designedbySandiafortheNRCtotracktheprogressionofsevereaccidentsinboilingwaterandpressurizedwaterreactors.ForUnit1,theeventwasclosetowhat’scalleda“hands-off”stationblackout.Fromthetimethetsunamistruck,essentiallynothingworked.ThelossofbothACandbatterypowerdisabledtheisolationcondensersand thehigh-pressurecoolant injection system (HPCI), aswell as the instruments for reading pressure and water level. Counting downfromthetimeoftheearthquake,thecorewasexposedafterthreehours,begantoundergodamageafterfourhours,andbyfivehourswascompletelyuncovered.

Atninehours,according to thisanalysis, themoltencoreslumped into thebottom of the reactor vessel, and by fourteen hours—if not sooner—it hadmelted completely through. By the time workers had managed to injectemergencywater into thevesselat fifteenhours,muchof the fuelhadalreadylandedonthecontainmentfloorandwasviolentlyreactingwiththeconcrete.

But even a straightforward “hands-off” blackout turned out to be toocomplex forMELCOR to fully simulate. For instance, although the code didpredictthatthecontainmentpressurewouldrisehighenoughtoforceradioactivesteamandhydrogenthroughthedrywellsealsandintothereactorbuilding, itscalculationof theamountofhydrogen that collectedat the topof thebuilding“just missed” being large enough to cause an explosion, according to RandyGauntt,oneofthestudy’sauthors.

AU.S. industry consultant,David Luxat, presented a simulation using theindustry’scode,calledMAAP5.Hissimulationalsopredictedthattheconditionswould not be right for a hydrogen explosion at the time when one actuallyoccurred.Hisspeculation:extrahydrogenleakedfromtheventintothereactor

building.Ultimately,theexplosionatUnit1remainedsomethingofamystery.AnotherissuethatexpertsdisagreedonwaswhatcausedtheUnit1reactor

vessel to depressurize suddenly around six or seven hours into the accident.Sandia argued that itwasprobablya rupture inoneof the steam lines leadingfromthevessel,orastuck-openvalve;othersbelieveditwasafailureofsomeofthetubesusedtoinsertinstrumentsintothevesseltotakereadings.Butnocodewas capable of predicting one of these events over another; and no one knewwhatactually tookplaceanyway.Suchconfirmationwillhave toawait a timewhenitissafetoenterthecontainmentandconductforensicexaminations.Eventhen, it is far from certain that the history of the accident will be fullyreconstructed,orallitslessonsrevealed.

ThesituationwasevenmurkierwhentryingtounderstandthemorecomplexeventsthatledtothemeltdownsatUnit3andthenUnit2.

ForUnit3,whichneverfullylostbatterypower,operatorswereabletorunthereactorcoreisolationcooling(RCIC)systemuntilitshutdown,andthentheHPCI system until they deliberately shut it down. Although the analystsgenerally agreed that core damage occurred sometime before 9:00 a.m. onMarch 13, there wasmuch disagreement about how extensively the core wasdamaged and whether it had in fact melted through the reactor vessel. Theanswersdependedontheamountofwaterthatactuallygotintothevesselfromthe operations ofRCIC,HPCI, fire pumps, and fire engines.Various analystsquestionedwhetherRCICandHPCIoperatedwellundersuboptimalconditions,andwhetherthepumpseverhadsufficientpressuretoinjectmeaningfulflowsofwater into the core. Assuming different amounts of water led to differentconclusions.Inthefinalanalysis,noonecouldpredictwithconfidencewhetherornottherewasvesselfailure.

TheexplosionatUnit3wasanotherpuzzle.Itappearedlargerthantheoneat Unit 1, but under the assumptions for water injection rates provided byTEPCO, neither the Sandia simulation nor the industry’s found that enoughhydrogenwasgeneratedtocauseanyexplosionatall.

The analysis of Unit 2 yielded even more mysteries. During the actualaccident, Unit 2 was initially a success story compared to its siblings. Eventhoughitlostbatterypower,thereactor’sRCICsystemoperatedfornearlythreedays.Underconventionalmodelingassumptions,itwouldhavefailedaroundanhourafter theeight-hourbatteries ranout.Therefore, theanalystshad to forcetheRCICsystemtokeepoperatingunderabnormalconditions in theirmodels,eventhoughtheydidn’tunderstandwhy.However, theyalsodidn’tknowhow

wellithadworked.AftertheRCICsystemfailed,workerstookseveralhourstostartseawaterinjection;bythen,coredamagewaswellunderway.AswithUnit3,therewassomuchuncertaintyabouttheamountofwaterthatreachedthecorethatnosimulationcouldpredictwithanydegreeofconfidencehowmuchfuelwasdamagedandwhetheritmeltedthroughthevessel.

Also unexplained was the fact that, although Unit 2’s RCIC system wastransferring heat from the core to the torus, themeasured pressurewithin thetoruswas not increasing asmuch as it should have been. In fact, someof themodels had to assume therewas a hole in the torus just tomake sense of thedata.Thisledtospeculationthattherehadindeedbeenaholeinthetorusfromearlyonintheaccidentorthatthetorusroomhadfloodedwithwaterfromthetsunami,whichhelpedtocoolitdown.

Ifitwasahole,itwouldhavehadtohaveformedwellbeforeworkersheardthemysteriousnoiseatUnit2onthemorningofMarch15thatmadethemthinkan explosion had damaged the torus. That was the only way to explain thepressure data. In any event, TEPCO later concluded that the noise didn’toriginateatUnit2atall,butwasanechooftheexplosionatUnit4thatoccurredat approximately the same time. The rapid pressure drop that instrumentsrecorded in theUnit2 toruswasattributedbyTEPCOto instrument failure.Aremote inspection made months after the accident did not reveal any visibledamagetothetorus.

So Unit 2 was apparently the only unit operating at the time of theearthquake thatdidnot experienceaviolenthydrogenexplosion.Onepossiblereasonforthisisinthe“silverlining”category:theopeningcreatedintheUnit2reactorbuildingby theUnit1explosionprevented thebuildupofanexplosiveconcentrationofhydrogengas.

AsfortheUnit4explosion,mostevidenceindicatesthattheculpritwasnothydrogenreleasedfromdamagedfuelinthespentfuelpool.Infact,thepoolwasneverasseriouslyindistressastheNRC,TEPCO,andmanypeoplearoundtheworldfeared.

Inspectionsofthespentfuelinthepoolusingremotecamerasdidnotseethekind of damage that would have been apparent if any fuel assemblies hadoverheatedandcaughtfire.Andsamplesofwaterfromthepooldidnotreflectthe radioactivity concentrations that would accompany damaged fuel. TEPCOwas so sure of this finding that it pursued another theory for the explosion:hydrogenhad leaked into theUnit 4 buildingduring the ventingoperations inUnit3nextdoor.

LikeUnits1and2,Units3and4sharedastackforgasexhaust,andsomeofthe piping from the two units was interconnected. Although closed valvesordinarilywouldhavekeptonereactor’sexhaustfromgettingintotheother,thevalveswere not operating properly as a result of the blackout. TEPCO foundfurtherevidenceforthistheorywhenitmeasuredhigherradiationlevelsonthedownstreamsideofthegasfiltersatUnit4thanontheupstreamside,indicatingthatradioactivegasflowedfromtheoutsideofthebuildingtotheinside.

Thisdidn’tmean,however,thattheUnit4poolwasneverindanger.TEPCObelievedthatthepoolhadlostuptotenfeetofwaterearlyintheaccidentastheresult of sloshing or some other unknown mechanism, causing the watertemperature to shoot up toward the boiling point. Fortuitously, there was asecond large pool of water—the reactor well—sitting on top of the reactorvessel.Thereactorwellisconnectedtothespentfuelpoolthroughagateandisfilledduringrefuelingtokeepfuelrodssubmergedatalltimes.Whenthewaterinthespentfuelpooldropped,waterflowedfromthewellintothepool,buyingtimeuntilaneffectiveexternalwatersupplywasestablished.

TheUnit2spentfuelpoolmaynothavebeenaslucky.Itwasnotoneofthepoolsthatcommandedmuchattentionduringtheearlydaysoftheaccident.Yetwhen sampling of the pool water was conducted in April 2011, higher thanexpectedlevelsofradioactivityweredetected.Evenmorestartlingwasarelativeabsenceofiodine-131inthepoolwatercomparedtotheamountofcesium-137.If the radioactivityhadoriginated in the reactor cores,more iodine-131wouldhavebeendetected.ThisledofficialsintheWhiteHouseOfficeofScienceandTechnology Policy to conclude that there was either mechanical or thermaldamagetosomeofthespentfuelinthepool.

Givenalltheuncertainty,thereislittlewonderthatanalystsstilldonotknowexactly how radioactivity was released into the environment, when it wasreleased, and where it came from. There were multiple and sometimesoverlappingperiodsofradioactivereleasesfromthedifferentunits.

Most experts agree that large releases onMarch 14 and 15, coupled withprecipitation,wereultimatelyresponsiblefortheextensiveareaofcontaminationstretchingnorthwestfromtheplanttoIitatevillage.TEPCOhasarguedthattheventing operations did not contribute significantly to radiation releases andtherefore that the reactor toruses were effective in scrubbing fission productsfromthesteamthatwasvented.ThecompanyclaimsthatUnit2wasthesourceofthelargestrelease,comingnotfromthetorusthroughaholethatmayormaynotexistbutfromthedrywell,whichunderwentarapiddropinpressureduring

thedayonMarch15.Inthisview,eventhereactorbuildingexplosionsatUnits1 and 3, as dramatic as they appeared, did not contribute asmuch to off-sitereleases,mainlybecause thebuildingscoulddo little tocontain radiationevenwhentheywereintact.

However,otheranalystshavelookedatthesamedataandconcludedthattheventingdidcauselargereleasesandthatscrubbinginthetoruswasnoteffective.ThisisacrucialtechnicalissuefortheU.S.debateoverwhetherfiltersshouldbeinstalled on the hardened vents atMark I andMark II BWRs. Until forensicinvestigationsnarrowdownthevariouspossibilities,though,alloftheseclaimsremainintherealmofspeculation.

Ultimately, based on off-site measurements and meteorological data, itappears thatFukushimaDaiichiUnits1 through3,onaverage, released to theatmosphere less than 10 percent of the radioactive iodine and cesium that thethreecorescontained.ThatwouldbegenerallyconsistentwiththeresultsfromcomputermodelingofstationblackoutsinstudieslikeSOARCA.Buttherearesomanyunexplainable featuresof theaccident rightnow that the similarity inresultsmaybemerecoincidence.

What is clear is that, in terms of the amount of radiation released, theFukushimaDaiichiaccidentwasfarfromaworst-caseevent.Thismeantthatthedirest scenarios that the National Atmospheric Release Advisory Center(NARAC)estimated forTokyoandpartsof theUnitedStates, basedonmuchhigher radiation releases, never occurred. Fukushima will not challengeChernobyl’s ranking as the world’s worst nuclear plant accident in terms ofradioactive release, although itwill remain classified a level7 accidentby theIAEA.

The difficulties analysts have explaining what happened in 2011 atFukushimaareonlycompoundedwhen theyuse the samecomputermodels topredict the future. Inotherwords,whencomputermodelscannot fullyexplainyesterday’saccident, theycannotaccuratelysimulate tomorrow’saccident.Yetthenuclearestablishmentcontinuestoplaceever-greaterrelianceonthesecodestodevelopsafetystrategiesandcost-benefitanalyses.

GLOSSARY

AC(alternatingcurrent)power:Themostcommonformofelectricalpower,such as that provided to household appliances plugged into wall outlets.OperatingnuclearpowerplantssupplyACpowertoanelectricalgridforusebyresidentialandindustrialcustomers.

AdvisoryCommitteeonReactorSafeguards:AnindependentcommitteethatadvisestheU.S.NRC.Thecommitteeismadeupofexpertsinavarietyoffields and is responsible for reviewing NRC safety studies, licenseapplications,andadvisingonproposedstandards.

B.5.b: Designation for orders issued by the NRC after the September 2001terrorist attacks, requiring additional safety equipment to be available asbackupintheeventofafireorexplosioncausedbyanairplanecrashingintoanuclearfacility.B.5.bis thetitleofasectionwithintheNRC’sOrderforInterimSafeguardsandSecurityCompensatoryMeasuresofFebruary2002.

beyond-design-basis accidents: Also called “severe” accidents. Accidentsequencesthatarepossiblebutthatwerenotfullyconsideredinthereactordesign process because they were judged to be too unlikely (see designbasis).

boilingwaterreactor(BWR):Anuclearpowerreactordesigninwhichwaterflowsupwardthroughthecore,whereitisheatedandallowedtoboilinthereactor vessel. The resulting steam then drives turbines, which activategeneratorstoproduceACpower.

cold shutdown: A reactor coolant system at atmospheric pressure and attemperaturebelow200degreesFahrenheitfollowingareactorcooldown.

common-modefailure:Multiplefailuresofstructures,systems,orcomponentsasaresultofasinglephenomenon.

containment building: A steel-reinforced concrete structure that encloses anuclear reactor. It is intended to minimize the release of radiation in theeventofadesign-basisaccident.Inaboilingwaterreactor,thecontainmentconsistsoftwoparts:thedrywellandthewetwell.

control rod: A rod that is used to control power output by controlling thenuclear chain reaction rate inside a reactor.This rod containsmaterial thateasily absorbs neutrons and can suppress nuclear fission when insertedbetween the fuel assemblies. In an emergency, all control rods fully insertintothereactorcoretostopthenuclearchainreaction.

core:Seereactorcore.cost-benefitanalysis:Asystematiceconomicevaluationofthepositiveeffects

(benefits) and negative effects (non-benefits, including monetary costs) ofundertakinganaction.

criticality:Thenormaloperatingconditionofareactorwherethenuclearchainreactionissustained.Areactorachievescriticality(andissaidtobecritical)wheneach fissionevent releasesasufficientnumberofneutrons tosustainanongoingseriesofreactions.

DC (direct current) power: The electrical current produced by batteries andfrominvertersthattransformACpowertoDCpower.

decayheat:Whenanatomicnucleusfissions,twosmallernucleiarecommonlyformed.Manyofthesefissionby-productsareunstableandreleaseradiationseeking to become stable. These radioactive emissions generate thermalenergy called decay heat. Even after a reactor core is shut down and itsnuclearchainreactionstopped, itcontinues togeneratesubstantialamountsofdecayheatthatcancausefueldamagefromoverheatingifnotremovedatasufficientlyhighrate.

defense-in-depth: Multiple independent and redundant layers of defense tocompensate for potential human andmechanical failures so that no singlelayerisexclusivelyreliedupon.Forexample,thearrayofemergencypumpsinstalledtocoolthereactorcoreduringanaccident,thecontainmentbuildingthat minimizes radiation escaping from a damaged reactor core, and theemergencyplansthatevacuatepeopleineventofaradiationreleaseareeachdefense-in-depthlayers.

designbasis:Therangeofconditionsandeventstakenexplicitlyintoaccountinthedesignofafacility,accordingtoestablishedcriteria,so that thefacilitycan withstand them without exceeding authorized limits by the plannedoperationofsafetysystems.

dose:Ameasureoftheenergydepositedbyradiationinatarget.dosimeter: A small portable instrument used to measure and record the total

accumulateddoseofionizingradiation.drycaskstorage:Apassivemeansofstoringreactorfuelthatprovidesradiation

shielding.Afterseveralyearsinaspentfuelpool,fuelcanbetransferredtoacask,typicallymadeofsteel,concreteandothermaterials.Onceinthecasks,thefueliscooledbynaturalairflow.

drywell: In a boiling water reactor with a Mark I containment, the drywellhousesthereactorvessel.Itresemblesaninvertedincandescentlightbulbandismadeofasteelshellsurroundedbysteel-reinforcedconcrete.

emergencycorecoolingsystems(ECCS):Reactorsystemcomponents(pumps,valves,heatexchangers, tanks,andpiping)specificallydesigned to removedecayheatfromthereactorcoreintheeventofafailurethatdrainsorleaksthenormalcoolingwater.

emergencydieselgenerators:Equipmentpermanentlyinstalledatnuclearplantsites that burns diesel fuel oil to generateAC power to supply emergencycorecoolingsystemsandotheremergencyequipmentwhenoff-sitepowerisunavailable.

emergency planning zone: An area of approximately ten-mile radiussurrounding a nuclear power plant where the principal exposure sourceswouldbewholebodyexternalexposuretogammaradiationfromtheplumeanddepositedmaterial,andinhalationexposurefromthepassingradioactiveplume.

externalevent:Potentiallydamagingeventsoriginatingfromoutsideanuclearplantsiteoroutsideofsafety-relatedbuildings.Typicalexamplesofexternalevents for nuclear facilities include earthquakes, tornadoes, tsunamis, andaircraftcrashes.TheNRCalsoconsidersplantfires tobe“externalevents”eveniftheyoriginatewithinplantbuildings.

feedandbleed:Aprocessinwhichmakeupwaterisaddedtoareactorvesselwhen theclosed-loopcoolingsystem ismalfunctioning.Themakeupwaterabsorbsheatgivenoffbythenuclearfuelandisallowedtoboil,or“bleed,”away.

FLEX:Shortfor“diverseandflexiblemitigationcapability,” theprogramwasdevisedbytheU.S.nuclearindustryinthemonthsfollowingtheFukushimaDaiichi accident. It comprises a variety of portable equipment that can berapidly installed in or deployed to a nuclear facility in the event of anaccidentornaturaldisastertoprovidebackupelectricalandcoolingsystems.

fuelassembly:Asetoffuelrodsloadedintoandsubsequentlyremovedfromareactorcoreasasingleunit.

fuel pellet: In light-water reactors, a thimble-sized ceramic cylinder(approximately ⅜-inch in diameter and ⅝-inch in length), consisting of

uranium (typically uranium oxide, UO2), which has been enriched toincrease the concentration of uranium-235 (U-235). Reactor cores maycontainupto10millionpellets,stackedinthefuelrodsandarrangedinfuelassemblies.

fuel rod:A hollow tubemore than twelve feet longmade from ametal alloycontaining zirconium that is filledwith fuel pellets and included in a fuelassembly.

hardenedvent:Ametalpipedesignedtowithstandthehigherpressurethatmayoccur inside containment during an accident that can be used to discharge(vent) the containment atmosphere to an elevated point. The normalventilationsystemforlowerpressuresusessheet-metalductssimilartothoseusedinhomesandoffices.

heat sink (alsoultimate heat sink): The nearby river, ocean, or lake used tocool the nuclear plant. During normal operation, one unit of electricity isgeneratedandtwounitsofwasteheatarerejectedtotheheatsinkforeverythreeunitsofthermalpowerproducedbythereactorcore.Duringaccidentsafter a successful scram, a smaller amountofwater from theultimateheatsinkisrequiredtocoolthereactorcoreandemergencyequipment.

high-pressure coolant injection (HPCI) system: Part of the emergency corecooling systems.HPCI is designed to inject substantial quantities ofwaterinto the reactorwhile it is at high pressure.Like the reactor core isolationcoolingsystem(RCIC),itcanrunwithoutACpoweraslongasDCpowerisavailable.HPCIusessteamproducedbythereactorcore’sdecayheattospinaturbineconnectedtoapump.

hypocenter:Thepointoftheearth’scrustwherearuptureinitiates,creatinganearthquake.

International Nuclear and Radiological Event Scale (INES): A scaledevelopedbytheInternationalAtomicEnergyAgencytocommunicateinaconsistent way the safety significance of nuclear and radiological events.Eventsareclassifiedonascalewithsevenlevels, rangingfromlevel1(an“anomaly”)withlittledangertothegeneralpopulation,toalevel7(a“majoraccident”)withalargereleaseofradioactivematerialsandwidespreadhealthandenvironmentaleffects.TheChernobylandFukushimanuclearaccidentswerebothlevel7accidents.

MELCOR: A computer code developed for the NRC by Sandia NationalLaboratories.Itmodelstheprogressionofsevereaccidentsinboilingwaterandpressurizedwaterreactors.

meltdown:Large-scalemeltingofnuclearfuelrodsinthereactorcore.millirem:One thousandthof a rem (0.001 rem).Ameasureof radiationdose.

(Seerem.)millisievert:Onethousandthofasievert(0.001sievert).Ameasureofradiation

dose(seesievert).NuclearRegulatoryCommission,U.S.(NRC):Anindependentagencycreated

by the Energy Reorganization Act of 1974, replacing part of the formerAtomic Energy Commission (AEC). The NRC is made up of fivecommissioners appointed by the president, who serve staggered, five-yearterms. One member serves as chairman and acts as principal executiveofficer.Thecommissionformulatespolicies,developsregulationsgoverningnuclearreactorandnuclearmaterialsafety,issueslicensesandisresponsibleforoverseeingreactorandnuclearmaterialsafety.

off-sitepower: Power supplied to a power stationvia transmission lines fromtheelectricalpowergrid.

operatingbasisearthquake:Theearthquakethat,consideringtheregionalandlocalgeologyandseismology,andspecificcharacteristicoflocalsubsurfacematerial, could reasonably be expected to affect a nuclear plant during itsoperatinglife.

potassium iodide: A compound that provides protection to the thyroid fromexposuretoradioactiveiodine-131,whichisoneofthefissionproductsthatcan be released in a meltdown. Potassium iodide would not give anyprotection against any other radioactive isotope that may be released in ameltdownatanuclearpowerplant.

primarycontainment:Seecontainmentbuilding.pressurizedwaterreactor(PWR):Anuclearpowerreactordesignthatutilizes

two separate coolant loops, unlike a boiling water reactor. In the primaryloop,water iscirculated throughthereactorcoreandheated toaveryhightemperature by fission, but kept under high pressure to prevent it fromboiling.APWRessentially operates like a pressure cooker,where a lid istightly placed over a pot of heated water, causing the pressure inside toincreaseasthetemperatureincreases(becausethesteamcannotescape)butkeepingthewaterfromboilingattheusual212°F(100°C).Theheatedwaterispipedthroughtubescalledsteamgenerators,whichtransferheatenergytowaterinasecondaryloop,whereitisallowedtoboil.Theresultingsteamisused to drive turbine generators to produce electrical power. About two-thirdsoftheoperatingnuclearpowerplantsintheUnitedStatesarePWRs.

probabilisticriskassessment(PRA):Asystematicmethodforassessingthreequestions that theNRCuses todefine “risk.”Thesequestions consider (1)whatcangowrong,(2)howlikelyitis,and(3)whatitsconsequencesmightbe.TheNRCusesPRAtodetermineanumericestimateof risk toprovideinsights into thestrengthsandweaknessesof thedesignandoperationofanuclearpowerplant.

ProtectiveActionGuides (PAGs): Suggested precautions that state and localauthoritiescan takeduringanemergency tokeeppeople fromreceivinganamountof radiation judgedexcessivelydangerous to theirhealth.TheU.S.Environmental Protection Agency developed the PAG Manual to provideguidanceonactionstoprotectthepublic,suchashavingpeopleevacuateanareaorstayindoors.

RASCAL (Radiological Assessment System for Consequence Analysis): Acomputer code used by the U.S. NRC to make dose projections foratmosphericreleasesouttofiftymilesduringradiologicalemergencies.

reactor building: Also called the secondary containment, the structure of aboiling water reactor that completely surrounds the containment building.The reactor building houses the emergency core cooling systems and thespentfuelpool(atmostboilingwaterreactors).

reactor core: The central portion of a nuclear reactor that contains the fuelassemblies,moderator,controlrods,andsupportstructures.Thereactorcoreiswherefissionoccurs.

reactor coolant system:The reactorvessel (themetal pothousing the reactorcore), the piping and components attached to it, and the water containedinside that function to remove heat produced by the reactor core duringnormaloperationandaccidents.

reactor core isolation cooling (RCIC) system: A system designed to supplymakeupwater to a shutdown reactor to compensate for boil-off caused bydecay heat when the normal makeup system has failed or is otherwiseunavailable. Like HPCI, RCIC uses steam produced by the reactor core’sdecay heat to spin a turbine connected to a pump and can run in a stablefashionas longasDCpower isavailable toopen itsvalvesandcontrol itsturbinespeed.

rem(roentgenequivalentman):AunitprimarilyusedintheUnitedStatestomeasurethedoseequivalent(oreffectivedose),whichcombinestheamountof energy (from any type of ionizing radiation that is deposited in humantissue), alongwith themedical effects of the given type of radiation. The

relatedinternationalsystemunitisthesievert(Sv),whereonehundredremisequivalenttooneSv.

reliefvalve(alsosafetyreliefvalve):Valvesinstalledonreactorcoolantsystempipes for protection against damage caused by high internal pressure. Thevalves have springs that keep them closed normally. If pressure inside thepipe rises toohighor theoperators apply compressed air pressure, a reliefvalvewillopentoreducepressurebyallowingreactorcoolantsystemfluidtoflowintothewetwellofaboilingwaterreactor.

safe shutdown earthquake (SSE): The maximum earthquake potential forwhichcertain structures, systems,andcomponents, important to safety,aredesignedtosustainandremainfunctional.

Severe Accident Management Guidelines (SAMGs): A set of voluntarynuclearindustryguidelinesofthe1990stobeusedbyplantoperatorsintheeventofabeyonddesign-basisaccident inwhichcoredamagehadalreadyoccurredorwasimminent.

shutdown: A decrease in the rate of fission (and heat/energy production) toreachasubcriticalstateinareactor(usuallybytheinsertionofcontrolrodsintothecore).

sievert(Sv):Aninternationalunitofmeasurementforradiationdosage(1Sv=100rem).AccordingtotheWorldHealthOrganization,theaveragepersonisexposed to about three millisieverts a year of radiation, from naturallyoccurring, medical, and other sources. Exposure to about one thousandmillisieverts (one sievert) of radiation in a short period of time can causeacuteradiationsickness.

State-of-the-ArtReactorConsequenceAnalyses(SOARCA):Astudybegunin 2007 by the NRC to develop estimates of off-site radiological healthconsequencesforseverereactoraccidents.

source term: The amount and isotopic composition of material released (orpostulated to be released) from a facility. Used in modeling releases ofradionuclides to theenvironment,particularly in thecontextofaccidentsatnuclearinstallationsorreleasesfromradioactivewasteinrepositories.

SPEEDI: System for Prediction of Environmental Emergency DoseInformation.Japan’snationalmonitoringnetworktomeasurereal-timedoseassessments during radiological emergencies. Developed by the JapaneseaftertheThreeMileIslandaccident,itbeganoperationsin1986.

spentfuelpool:Apoolofreinforcedconcretetypicallyaboutfortyfeetdeepinwhich fuelassembliesarestoredbeneathat least twenty feetofwater.The

water, which circulates to provide cooling, also acts to shield radiation.These pools can be located above the reactor, as is the case with boilingwater reactors, or in an adjacent ground-level area, as is the case withpressurizedwaterreactors.

spentnuclearfuel:Nuclearreactorfuelthathasbeenusedtotheextentthatitcannolongereffectivelysustainachainreaction.

stationblackout:A complete loss of alternating current electric power to thestation.

suppressionchamber(andsuppressionpool):Seewetwell.torus:Seewetwell.turbine building: The building housing the turbine/generator and auxiliary

equipment.vent valves (also containment vent valves): A series of valves that factored

significantlyintheFukushimaaccident.Thecontainmentventvalvesremainclosed during normal operation and during design basis accidents. Duringbeyonddesign-basisaccidents, thecontainmentventvalvesmaybeopenedtoallowgasestobedischargedtocontrolhydrogenbuildup,removeheat,orlowerpressure.

wetwell: In a boilingwater reactor, thewetwell sits below the drywell and isconnectedtoitthroughaseriesofpipes.Thewetwellissometimescalledatorus,suppressionchamberorsuppressionpool.Itcontainsalargevolumeofwater that acts as an “energy sponge” to absorb energy released from thereactorcoolantsystemduringanaccident.

KEYINDIVIDUALS

InJapanShinzoAbe,primeminister(December2012–)YukiyaAmano,director,InternationalAtomicEnergyAgencyYukioEdano,chiefcabinetsecretary(January2011–September2011);minister

of economy, trade, and industry (September 2011–December 2012) ToruHashimoto,mayor,Osaka

Yotaro Hatamura, chairman, Investigation Committee on the Accident at theFukushima Nuclear Power Stations of Tokyo Electric Power CompanyNaomiHirose,president,TEPCO(June2012–)

GoshiHosono,ministerof theenvironment (September2011–December2012)Katsuhiko Ishibashi, seismologist and nuclear safety proponent BanriKaieda, minister of economy, trade, and industry (January 2011–August2011)NaotoKan,primeminister(June2010–August2011)

TsunehisaKatsumata,chairman,TEPCO(June2008–May2012)ToshisoKosako,radiationsafetyexpert,advisor toPrimeMinisterKanHaruki

Madarame,chairman,NuclearSafetyCommissionKiyooMogi,seismologistandnuclearsafetyproponentKoichiro Nakamura, deputy director general, Nuclear and Industrial Safety

AgencyToshioNishizawa,president,TEPCO(June2011–May2012)YoshihikoNoda,primeminister(September2011–December2012)MasatakaShimizu,president,TEPCO(June2008–June2011)KazuhikoShimokobe,chairman,TEPCO(April2012–)AileenMiokoSmith,executivedirector,GreenActionIchiroTakekuro,TEPCOliaisontoJapaneseprimeministerKanMasao Yoshida, site superintendant, Fukushima Daiichi Nuclear Power Plant

AtsufumiYoshizawa,FukushimaDaiichiemployee

InAmericaStevenAoki,deputyundersecretary,U.S.DepartmentofEnergyGeorgeApostolakis,commissioner,U.S.NuclearRegulatoryCommissionJames

K. Asselstine, commissioner, U.S. NRC (1982–1987) Bill Borchardt,executivedirectorforoperations,U.S.NRC

EliotBrenner,OfficeofPublicAffairs,U.S.NRCScottBurnell,OfficeofPublicAffairs,U.S.NRCCharles Casto, deputy regional administrator, U.S. NRC; headed the NRC’s

teaminJapanBillDedman,reporterforNBCNewsandmsnbc.comKirklandDonald,director,OfficeofNavalReactors,U.S.DOEDaniel Dorman, deputy director, Office of Nuclear Material Safety and

Safeguards,U.S.NRC(lateramemberoftheNRC’sNear-TermTaskForce)Jack Grobe, deputy director, Office of Nuclear Reactor Regulation, U.S.NRC(lateramemberoftheNRC’sNear-TermTaskForce)GregoryJaczko,chairman,U.S.NRC(2009–2012);NRCcommissioner (2005–2009)AnnieKammerer,seismologistandearthquakeengineer,U.S.NRC

AllisonMacfarlane,chairman,U.S.NRC(2012–)WilliamD.Magwood,commissioner,U.S.NRCDr.Charles“Charlie”Miller,director,OfficeofFederalandStateMaterialsand

Environmental Management Programs, U.S. NRC (later the chair of theNRC’sNear-TermTaskForce)JohnMonninger,deputychiefofstaffforthechairman, U.S. NRC, and member of the NRC’s team in Japan Michael“Mike”Mullen,chairman,JointChiefsofStaff

WilliamC.Ostendorff,commissioner,U.S.NRCTonyPietrangelo,chiefnuclearofficer,NuclearEnergyInstituteJohnV.Roos,

U.S.ambassadortoJapanBrianSheron,director,OfficeofNuclearRegulatoryResearch,U.S.NRCKristineL.Svinicki,commissioner,U.S.NRCJimTrapp,branch chief,U.S.NRC, andmemberof theNRC’s team in Japan

StephenTrautman,deputydirector,OfficeofNavalReactors,U.S.DOEAnthonyUlses,chief,ReactorSystemsBranch,U.S.NRC,andmemberof the

NRC’steaminJapanMartinVirgilio,deputyexecutivedirector,ReactorandPreparednessPrograms,U.S.NRC

MikeWeber,deputyexecutivedirector,U.S.NRCJimWiggins,director,OfficeofNuclearSecurityand IncidentResponse,U.S.

NRC

U.S.BOILINGWATERREACTORSWITH“MARKI”AND“MARKII”CONTAINMENTS

REACTORS CONTAINMENTS LOCATION

BrownsFerry1BWR-MARKI

Alabama

BrownsFerry2BWR-MARKI

Alabama

BrownsFerry3BWR-MARKI

Alabama

Brunswick1BWR-MARKI

NorthCarolina

Brunswick2BWR-MARKI

NorthCarolina

CooperBWR-MARKI

Nebraska

Dresden2 BWR-MARKI Illinois

Dresden3BWR-MARKI

Illinois

DuaneArnoldBWR-MARKI

Iowa

Fermi2BWR-MARKI

Michigan

FitzPatrickBWR-MARKI

NewYork

Hatch1BWR-MARKI

Georgia

Hatch2BWR-MARKI

Georgia

HopeCreek1BWR-MARKI

NewJersey

MonticelloBWR-MARKI

Minnesota

NineMilePoint1BWR-MARKI

NewYork

OysterCreek NewJersey

OysterCreekBWR-MARKI

NewJersey

PeachBottom2BWR-MARKI

Pennsylvania

PeachBottom3BWR-MARKI

Pennsylvania

Pilgrim1BWR-MARKI

Massachusetts

QuadCities1BWR-MARKI

Illinois

QuadCities2BWR-MARKI

Illinois

VermontYankeeBWR-MARKI

Vermont

ColumbiaGenerationStationBWR-MARKII

Washington

LaSalle1BWR-MARKII

Illinois

LaSalle2BWR-MARKII

Illinois

Limerick1 Pennsylvania

Limerick1BWR-MARKII

Pennsylvania

Limerick2BWR-MARKII

Pennsylvania

NineMilePoint2BWR-MARKII

NewYork

Susquehanna1BWR-MARKII

Pennsylvania

Susquehanna2BWR-MARKII

Pennsylvania

Source:U.S.NuclearRegulatoryCommission.

NOTESANDREFERENCES

ThefollowingarekeysourcesandexplanatorynotesforFukushima:TheStoryofaNuclearDisaster.Fullreferences are available at Fukushimastory.com, including links to documents, reports, illustrations, andothermaterialsthatplayedaroleinthepreparationofthisbook.

The sources for this book include contemporaneous news accounts published in the United States,Japan,andelsewhere.Extensiveusewasmadeof informationgatheredbyseveral investigations into theFukushima Daiichi accident that were conducted by official Japanese panels, international industryassociations, scientific groups, and the plant’s owner, the Tokyo Electric Power Company, as well asanalysesbynuclearsafetyorganizations,notablytheUnionofConcernedScientists.

PlayingamajorroleinthisbookaretranscriptsmaintainedbytheNuclearRegulatoryCommissionofconversationsamongNRCexpertsintheUnitedStatesandinJapan.Thesetranscripts,plusthousandsofpagesofNRCdocumentsande-mailsrelatedtothecommission’sresponseduringandaftertheaccident,provide an inside view of the challenges and uncertainties facing those charged with protecting publichealthandsafety.

The book also draws on the long legislative and regulatory histories of the Nuclear RegulatoryCommissionand itspredecessor, theAtomicEnergyCommission.Public transcriptsofmeetings,writtenopinions,congressionalhearings,andscientificreportswerealsoincorporated.

1.March11,2011:“ASituationThatWeHadNeverImagined”

Newsaccounts of the accident provideddescriptions of the early hours of the accident. TheEarthquakeEngineering Research Institute’s reports on the Tohoku earthquake (available atwww.eeri.org/2011/03/tohoku-japan/) offered valuable information, as did two articles published in theBulletinoftheAtomicScientists,“Fukushima:TheMythofSafety,theRealityofGeoscience”(September–October 2011) and “Fukushima in Review: AComplexDisaster” (March 8, 2012). Additionalmaterialcame from the InvestigationCommittee on theAccident atFukushimaNuclearPower Stations of TokyoElectricPowerCompany(www.cas.go.jp/jp/seisaku/icanps/eng/),hereinafterthe“Hatamurareport,”andthe Institute of Nuclear Power Operations, “Special Report on the Nuclear Accident at the FukushimaDaiichi Nuclear Power Station,” November 2011 (available atwww.nei.org/corporatesite/media/filefolder/11_005_Special_Report_on_Fukushima_Daiichi_MASTER_11_08_11_1.pdf

1. The Richter scale for earthquake magnitude has been replaced among scientists by the momentmagnitude scale, which is now the most commonly cited measure for medium to large earthquakes.AlthoughitisnotidenticaltotheRichterscale,themomentmagnitudescaleprovidescomparablenumbers,andtheyaretheonesusedinthisbook.Themomentmagnitudescaleisalogarithmicscaleinwhicheachunitof increase inmagnitude represents a thirty-two-fold increase in the total energy released.ScientistsalsousetheModifiedMercalliIntensityScale,whichmeasurestheeffectsofanearthquakeratherthanitsmagnitude.Thisscalehastwelvelevelsofintensityrangingfromimperceptibleshaking(I)tocatastrophicdestruction(XII).TheJapanMeteorologicalAgency(JMA)usesyetanotherscalerangingfromI toVII,

thehighestcategory.OnMarch11,2011,muchoftheeastcoastofJapanreceivedIntensityVIIshaking,aboutthesameasModifiedMercalliIntensityX.

2.Eachcontrolrod(CR)isequippedwithpositionindicators.Whenallthecontrolrodindicatorsreflectthefullyinsertedposition,thisalarmsavestheoperatorsthetroubleofhavingtocheckeachcontrolrod’sstatus.

3.Alternating current (AC) electricity powers homeappliancesplugged into electrical outlets.Directcurrent (DC) electricity powers portable electronic devices with batteries. Many of the components ofemergency systems at nuclear powerplants, likemotor-drivenpumps andvalves, needACelectricity torun.DCpowerfrombatteriescanbeusedfortheinstrumentationandcontrolsystemsthatoperatesystemsliketheisolationcondensersandRCIC.

4.ThewordtsunamiwasintroducedtoEnglishspeakersbytwojournalistsworkinginJapanatthetimeofthe1896disaster.ElizaRuhamahScidmore,anAmerican,wroteanaccountoftheJune15earthquakeandtsunamifortheSeptember1896issueofNationalGeographicmagazine:“Therewereoldtraditionsofsuchearthquakewavesonthiscoast,”shewrote.Scidmorewouldgoontobecomethefirstfemaleboardmember of theNationalGeographic Society and play a role in planting cherry trees along the PotomacRiver.Thesecond journalist todescribe thedisasterwasLafcadioHearn.Writing in theDecember1896AtlanticMonthly,Hearnreported:“FromtimeimmemorialtheshoresofJapanhavebeenswept,atirregularintervalsofcenturies,byenormoustidalwaves....TheseawfulsuddenrisingsoftheseaarecalledbytheJapanesetsunami.”

5.TheU.S.GeologicalSurveyhasofficiallydesignatedittheGreatTohokuEarthquake.6.TheriskofstationblackouthadbeenraisedwithintheNuclearRegulatoryCommissioninthe1970s.

Thenuclearindustryresistedthisconcern,assertingthatthelikelihoodoftheelectricalgridandtheon-siteemergencydieselgeneratorsallfailingsimultaneouslywaslow.ThatargumentprevaileduntilMarch1990,when theUnit 1 reactor at theVogtle plant inGeorgia actually experienced a blackout. Fortunately, theplantwasshutdownwhen theblackoutoccurred,givingworkerssufficient time to repair theemergencydieselgeneratorandavertdisaster.

7.FukushimaDaiichi is loosely translatedas“FukushimaOne”andFukushimaDainias“FukushimaTwo.”Thedesignationisbasedontheirconstructiondates.

8.Japanhastwoincompatibleelectricitygrids.Thegridsupplyingthenortheasternhalfofthecountry,includinganareaservedbyTEPCO,operatesat fiftyhertz.Power to thewesternportionof the island issixtyhertz.Thetwogridsarosefromtheoriginalsourcesofgenerationequipment:Germany(fiftyhertz)and theUnited States (sixty hertz). The inability to share large amounts of electricity between the gridscompoundedenergyshortagesduringtheFukushimaaccidentandcandosoatothertimeswhendemandpeaksinoneareabutnottheother.

2.March12,2011:“ThisMayGetReallyUgly...”

Transcriptsof conversations recordedat theNRC’s emergencyoperations centeraswellas e-mailsandotherNRCdocumentswereusedinthischapter.Newsaccounts,scientificjournalarticles,andinformationfrom theU.S.GeologicalSurveywereutilized.Detailsof theaccidentat theTokainuclear facilitywerepublished in “Accident Prone: The Trouble at Tokai-Mura,” Bulletin of theAtomic Scientists,March–April2000.InformationalsocomesfromtheHatamurareport.

1. For disclosure, one of the authors (Lochbaum) has traveled through the “revolving door”: havingworkedformorethanadecadeintheU.S.nuclearpowerindustry,hemovedtotheUnionofConcernedScientists(UCS)formorethanadecade,wenttotheNRCformorethanayear,thenreturnedthroughthedoortotheUCS.

2. As a result of the Kashiwazaki-Kariwa fire, TEPCO required that fire engines be stationed at itsnuclearplants,whichprovedbeneficialatFukushimaDaiichiinthedaysafterMarch11.

3.March12Through14,2011:“WhattheHellIsGoingOn?”

The Hatamura investigation, NRC transcripts, and the Institute for Nuclear Power Operations’ SpecialReportontheNuclearAccidentat theFukushimaDaiichiNuclearPowerStation,INPO11-005(Atlanta:Institute of Nuclear Power Operations, 2011),www.nei.org/corporatesite/media/filefolder/11_005_Special_Report_on_Fukushima_Daiichi_MASTER_11_08_11_1.pdfwereusedinthischapter.

1.Ifeventhatlimitedinformationhadbeenheeded,investigatorslaterconcluded,evacuationroutesforseveralcommunitiesnorthwestofthereactorscouldhavebeenalteredtoavoidexposingthepublictotheradiationplumestheythoughttheywerefleeing.

2.Wateractsasa“moderator”inreactorslikethoseatFukushima,slowingneutronssothattheymorereadily split atoms. Fuel,water, and control rods are carefully arranged to ensure that the nuclear chainreactioncanbecontrolled.Butinjectingwaterintothepotentiallymoltencorecarriedtheriskofincreasingthe fission rate and possibly restarting a chain reaction. For this reason, water reserves maintained atreactorsaremixedwithboricacid,aneutronabsorber,beforebeinginjectedintothecore.Theboricacidcanhelppreventachainreaction.

3.Those standards are set by theEnvironmental ProtectionAgency and known as ProtectiveActionGuides,orPAGs.

4.Ahardenedvent is a separateventpipe capableofwithstandingheavier loadsduring an accident,suchasa stationblackout. It isa safetymechanismfor relievingpressure in theprimarycontainmentbyreleasingsteamandradioactivityatanelevatedpointoutsidethereactorbuilding.

5.IntheeventofanuclearplantdisasterinvolvingradiationreleasesintheUnitedStates,thestates,notfederalagencies,decideonpublicprotectionmeasureslikeevacuationsandsheltering.TheNRC’sroleistoprovideinformationtostateauthoritiestoinformtheirultimatedecisions.

6.Inpressurizedwaterreactors,thespentfuelpoolsarelocatedinbuildingsadjacenttoandoutsideofthecontainment.Thisseparationmakesitlesslikelythatreactorissueswillaffectspentfuelpoolsandviceversa. The spent fuel pools are at or below ground level; this placement makes it easier to add water,becausesmallerpumpsareneededtomovewateracrossthegroundthantopushitupfivefloors.ButeventhePWRspentfuelpoolstypicallyhavespacebelowthemwherewatercouldquicklydrainifthepoollinerwerebreached.

7.Duringnormaloperation,steamproducedinsidethereactorvesselistransportedthroughfourlargepipes.Eachpipeisequippedwiththreeorfourreliefvalves,whichautomaticallyopenwhenpressurerisesorwhenpressurerisksaretoohigh.Thereliefvalvescanalsobemanuallyopenedfromthecontrolroom—whenpower is available—toallow theoperators to reducepressure in the steam lines and in the reactorvesselitself.Whenareliefvalveisopen,steamflowsviaametalpipeintothetorus,whereitisdischargedbeneaththesurfaceofthewater.Thus,theheatenergyfromthesteamremainsinsidethecontainment.Thecontainmentventvalves,incontrast,transferenergytotheatmosphereoutside.

8.TheU.S.NRCdoesnotlimittheamountofradiationworkersmayreceiveinanemergency.TheU.S.EnvironmentalProtectionAgencyhassetvoluntaryguidelinesofuptotwenty-fiverem(250millisieverts)forlife-threateningemergencies.

4.March15Through18,2011:“It’sGoingtoGetWorse...”

NRCtranscripts,congressionalhearingtestimony,andtheHatamurareportprovidedinformationforthischapter, as well as testimony delivered to subcommittees of the House Committee on Energy andCommerce,“TheFiscalYear2012:DepartmentofEnergyandNuclearRegulatoryCommissionBudgets,”JointHearingBeforetheSubcommitteeonEnergyandPowerandtheSubcommitteeonEnvironmentandthe Economy, 112th Cong., March 16, 2011, www.gpo.gov/fdsys/pkg/CHRG-112hhrg68480/pdf/CHRG-

112hhrg68480.pdf,andtotheSenateEnvironmentandPublicWorksCommittee,“FullCommitteeBriefingon Nuclear Plant Crisis in Japan and Implications for the United States,” March 16, 2011,www.epw.senate.gov/public/index.cfm?FuseAction=Hearings.Hearing&Hearing_ID=bb6c78e6-802a-23ad-4c7b-9aa7a3bb0c31.

1.MasaoYoshidadiedofesophagealcanceronJuly9,2013,atagefifty-eight.InNovember2011,afterbeingdiagnosedwiththedisease,hetookaleaveofabsencefromTEPCO.MedicalexpertssaidhiscancerwasunrelatedtoradiationexposurefromtheaccidentatFukushimaDaiichi.

2. Casto had just three hours to pack before boarding the plane bound for Narita Airport. Flightpersonnel,noticingCasto’sshirtwithitsNRClogo,soonrelocatedhimtoaseatinthenearlyemptyfirst-class section and began peppering him with questions about the accident in Japan. Uppermost in theirminds:was it safe to even fly into the country?Uponarriving inTokyo,Casto soondiscovered that hischoiceofclothing—whathecalls“emergencyresponsecasual,”poloshirtsandkhakis—wasnotsuitablefor his formalmeetingswith the Japanese.He called hiswife and asked her to FedEx every suit in hiscloset.

3.TheNRC’sOfficeofResearchhadneglectedtoprovideCastowithmorerecenttechnicalanalysesfrom the agency’s State-of-the-Art Reactor Consequences Analyses program. These analyzed accidentscenariosverysimilartothoseoccurringatFukushimainevenmoredetail.

4. B.5.b is the title of a section within the NRC’s Order for Interim Safeguards and SecurityCompensatoryMeasuresofFebruary2002.

5.TheroleplayedbyJapan’sSelf-DefenseForces(SDF)wasassymbolicasitwasmaterial.AboutonehundredthousandSDFtroopshadbeencalledupbythegovernmentonMarch11torespondtothenaturaldisaster.AsconditionsatFukushimaDaiichideteriorated,theSDFmissionwasbroadenedtohelpwiththereactorcrisis.“TheSDFoperation[atFukushimaDaiichi]encouragedothers. . . tosaythatthisproblemwasnotjustTEPCO’saccident,itwasJapan’s,”PrimeMinisterKanlaterexplained.“EveryonestartedtofeelstronglythatthiswasaboutwhetherJapanwouldsurvive.”

5.Interlude—SearchingforAnswers:“People...AreReachingtheLimitofAnxietyandAnger”

This chapter drew on documents from the NRC; National Diet of Japan, The Official Report of theFukushima Nuclear Accident Independent Investigation Commission (Tokyo: National Diet of Japan,2012), warp.da.ndl.go.jp/info:ndljp/pid/3856371/naiic.go.jp/wp-content/uploads/2012/09/NAIIC_report_lo_res10.pdf;theHatamurareport;andtheTokyoElectricPowerCompany.Inaddition,journalistBillDedmanprovidedbackgroundinformationandcorrespondence.

1.LikeotherJapaneseleadersduringthefirstweeksofthecrisis,Edanoroutinelyappearedbeforethecameras in sky-blue coveralls. The two-piece uniform is worn by officials during emergencies todemonstrateasenseofunitywithlaborcrews,reportedtheWallStreetJournal.Similartwo-piececompanyuniformswerewornbyTEPCOexecutivesthroughouttheaccident.

2.MorethanhalfthepeopleorderedtoleavetwelvemunicipalitiesaroundtheplantremainedunawarethattheirevacuationwastheresultofproblemsatFukushimaDaiichiuntilthemorningofMarch13,nearlytwodaysaftertheaccident,accordingtoalatersurvey.

6.March19Through20,2011:“GiveMetheWorstCase”

NRC transcripts and documents were a primary source in this chapter. Also cited is a report titled“OverviewoftheDepartmentofEnergy’sRadiologicalDoseAssessmentoftheFukushimaDaiichiNuclearPowerStationReleases,”preparedbyTerryKrausandBrianHuntofSandiaNationalLaboratories,SAND

Report2012-1226C,astarnmjss.nmcourts.gov/speakernotes/Japan_CM_Overview_Brief.pdf.

Thischapteralsoutilizedinformationobtainedfroma2012UnionofConcernedScientistsFreedomofInformationActrequesttotheWhiteHouseOfficeofScienceandTechnologyPolicy.

1. The accuracy of water-level readings was a chronic problem at Fukushima Daiichi. Water levelindicators for the reactor cores themselves were erroneous, in addition to the uncertainty about watercoveringthespentfuel.

2.Oncetheuseoffreshwatercouldberestored,thesaltdepositsbuildingupinsidethereactorwouldbegintodissolve,allowingcoolingwatertocirculatemoreeffectively.

3.MELCORisacomputercodedevelopedfortheNRCbySandiaNationalLaboratories.Itmodelstheprogressionofsevereaccidentsandcanestimatesourcetermsunderavarietyofaccidentscenarios.

7.AnotherMarch,AnotherNation,AnotherMeltdownReportof thePresident’sCommissionon theAccident atThreeMile Island:TheNeed forChange:TheLegacy of TMI (Washington, DC: U.S. Government Printing Office, 1979), available atwww.threemileisland.org/downloads/188.pdf, provided historical materials in this chapter. Additionaldetails can be found at the NRC’s “Backgrounder on the Three Mile Island Accident,”www.nrc.gov/reading-rm/doc-collections/fact-sheets/3mile-isle.html.

1.AccordingtoasurveybytheKemenyCommission,theUnionofConcernedScientistsledthelistoforganizationsthemediareliedonduringtheaccident.

8.March21ThroughDecember2011:“TheSafetyMeasures...AreInadequate”

Interviewwith Charles Casto of the NRC, findings of theHatamura investigation, and NRC documentsprovided background for this chapter, as well as the article “The Radiological and PsychologicalConsequencesoftheFukushimaDaiichiAccident,”BulletinoftheAtomicScientists,September–October2011.

1. Japan’s demonstration breeder reactor, Monju, generated power for only a few months before asodiumfiredisableditinDecember1995.Afterplantoverseersfinallyobtainedpermissiontorestartitin2010,anotheraccidentshutitdownuntilatleast2014.

9.UnreasonableAssurancesThis chapter uses information from numerous articles from the trade newsletters NucleonicsWeek andInsideN.R.C.datingtotheearly1980s.ItdrawsfromnumerouspublicdocumentsfromtheNRC,GeneralAccounting Office (now the Government Accountability Office), Congressional Research Service, theFederalRegister,andTEPCO.Italsodrawsupontwooutstandingbooks:CitizenScientistbyFrankvonHippel (New York: Simon & Schuster, 1991), 19–21, and Tritium on Ice by Kenneth D. Bergeron(Cambridge,MA:MITPress,2001),57–58.

1. When the NRC staff is considering “especially important or controversial rules,” the agencypublishes what it calls an Advance Notice of Proposed Rulemaking, laying out the issue and solicitingcommentsfromthepublicinadvanceofdevelopingadraftrule.Ordinarilypubliccommentwouldnotbesoughtuntilafterpublicationofadraftrule.

2.Abackfit is amodification of or addition to systems, structures, components, or the design of anexistingnuclearplantresultingfromchangesintheNRC’srulesorreinterpretationsofoldones.

3.Also,bynothavingtosubmitalicenseamendment,ownersavoidedgivingthepublicanopportunityto intervene and challenge its adequacy. Any “voluntary” upgrades would be conducted outside publicscrutiny.

4.WhentheNRCinspectedU.S.nuclearplantsshortlyafterFukushima,itfoundthatwhileallplantshadSAMGs,23percentdidnottrainworkersonthetasksassignedtothemintheSAMGs,and40percentnever conducted exercises using the SAMGs to see whether workers could successfully follow theguidelines.Inaddition,fewerthanhalftheplantsupdatedtheirSAMGstoreflectmodificationsmadetotheplants.

5.TwoexamplesillustratehowtheNRC’sriskswordwasrazorsharpononesideandNerf-likeontheother. In the1990s, twodecadesof experience found little damage inpipes and theweldsholding themtogether, indicating that the inspection requirements were unnecessarily strict. As a result, the NRCsignificantly reduced the frequency of pipe and weld inspections. On the other hand, when evidenceemergedthaticecondensersandtheMarkIIIwerevulnerabletocontainmentfailureinstationblackouts,theNRCrefusedtostrengthenitsrulestorequirebackuppowerfortheignitersystemsneededtoburnoffhydrogen.

6.According to aMarch2011e-mail fromNRCstaffmemberMartinStutzkeconcerning the IndianPointplant,“thelicenseetoldustheydoes[sic]notmaintaintheirseismicPRAs...there’slittleregulatorymotivationfor themtodoso. It’ssomewhatunderstandable that the licenseewouldfocuson the internaleventCDF[coredamagefrequency]...andtendtoignorethecontributionsfromearthquakesandfires.”

7.Through theprocessof“radiolysis,”oxygenwouldstart tobuildupas radiationbrokewaterapartintooxygenandhydrogenmolecules.

10.“ThisIsaClosedMeeting.Right?”

ThischapterisindebtedtoseveralcontemporaneousstoriesabouttheCRAC2reportbyMiltonBenjaminintheWashingtonPostandRobertSangeorgeofUnitedPressInternational,aswellasKennethBergeron’sTritiumonIce.Italsoreferencesthe2003articleinthejournalScienceandGlobalSecurity,R.Alvarezetal.,“Reducing theHazardsofStoredSpentPower-ReactorFuel inTheUnitedStates,”whichoneofus(Lyman) co-authored. In addition, it draws on numerous NRC documents originally withheld from thepublicontheSOARCAprogramthatwerereleasedtoUCSundertheFreedomofInformationActin2011.ItalsoreliesonotherNRCandACRSpublicdocuments,includingsomereleasedunderFukushima-relatedFOIAs.

1.TheCenterforResponsivePolitics,whichtrackslobbyingandcampaignexpenditures,reportedthatfrom 2008 through 2010 the Nuclear Energy Institute spent more than $6 million lobbying the federalgovernmentonnuclearissues.Largeutilitiesandnuclearmanufacturersspentmillionsmore.

OnFebruary9,2012,theNRCcommissionersvoted4–1toapprovelicensestoconstructthereactorsattheVogtlenuclearcomplex,about170mileseastofAtlanta.(NRCchairmanGregoryJaczkocastthelone“no” vote, saying, “I cannot support issuing this license as if Fukushima had never happened.” JaczkothoughtthatlessonslearnedfromtheJapanesedisastercouldleadtheNRCtoadoptnewrequirementsforU.S. plants, and he argued that any new licenses should be conditioned on plant owners’ agreement toincorporate all safety upgrades that the NRC might require in the future.) Two reactors already wereoperating at the facility, and upon completion this would become the nation’s largest private multiple-

reactorcomplex.2.In1983,forexample,theNRCrequiredthatanytestimonyontheconsequencesofanaccidentatthe

IndianPointnuclearplantalsohad toaddress theprobabilities. Inallcases, theNRCargued, thosewereverylow.

3.Oneoftheauthorsofthisbook,EdwinLyman,wasamongseveralco-authorsofthestudy.4.McGaffiganwasclearedaftertheNRCstaffmemberstoldtheinspectorgeneralthattheyhadarrived

independentlyattheirconclusionsrebuttingtheirstudy.Thestaffandthecommissionerwereconvenientlyonthesamewavelength.

5.TheNRCOfficeofNuclearRegulatoryResearchconductssomeofitstechnicalworkin-housebutfarmsoutmostofittoexternalcontractors,primarilystaffattheEnergyDepartment’snationallaboratories.

6.ThetwoPeachBottomreactorsarealmostidenticaltoFukushimaDaiichiUnits2–5.7.TheNRCusesthetermconservativeinthesenseofconservativefactorofsafety,awidelyusedterm

relatedtobuildinginextrasafetymarginsforvariousproductsormodels.8. The CRAC2 study used accident source terms that dated to the 1975 Reactor Safety Study. The

worst-casesourcetermwasdenoted“SST1.”SST1postulatedarelease,atninetyminutesaftertheaccidentbegan,ofaverylargefractionoftheradioactivematerialwithinthecore.

9.TheCRAC2radiationreleasesweregenerallymuchgreaterthantheSOARCAvalues:67percentofthecesium-137and45percentoftheiodine-131inthecore,comparedwith2percentand12percent,forexample.And theCRAC2 releasewas assumed to begin one and a half hours after the station blackoutoccurred, while the SOARCA release occurred eight hours for the Peach Bottom short-term stationblackout.

10.WhentheSOARCAstudywasfinallyreleasedinJanuary2012,thegrand“communicationsplan”thathadbeensuchaprioritywhentheprojectwaslaunchedyearsearlierincludeditsowntypeofnumericalsleightofhand:thesizeofthetype-face.Thebrochuredetailingtheresultsfeaturedbargraphsincludingonlythedatafromtheten-milezoneinitscomparisontoCRAC2.Fortheareasbeyond,smallprintonthenextpagenotedthat“thedifferencediminisheswhenconsideringlargerareas.”

11.2012:“TheGovernmentOwesthePublicaClearandConvincingAnswer”

Contemporaneousnewsaccountswereusedinthischapter.

1. In that regard, the limited, carefully scripted accident assumptions resembled the SOARCA studymethodologyusedby theNRC,whichdisregardedaccidentsdeemed too improbableand—at least in themitigatedmodels—assumedthatallemergencyactionsweresuccessful.

2.MeservewaslikelyreflectingonhisownexperienceasNRCchairman.Inlate2001,hepresidedovertheagencywhen itmade thenear-disastrousdecision toallowtheDavis-Besseplant inOhio tocontinueoperatinguntilthenextscheduledrefuelingoutage,despiteaccumulatingevidenceofapotentiallyseriousproblemattheplant’ssinglereactor.Basedoncircumstantialbutcompellingevidence,theNRCstaffhaddraftedanorderthatwouldrequiretheplanttobeshutdownforsafetyinspections,asteptheNRChadnottaken sinceMarch 1987. But senior NRCmanagers shelved the order for economic reasons.When thereactorwas finally shutdown,workersdiscoveredapineapple-sizedhole in the reactorvesselhead.TheplanthadcomewithinmonthsofanaccidentthatcouldhaveexceededtheseverityofThreeMileIsland.

3.InJapan,utilitiessettheirownratesinacomplexformulathatrewardsspending;themoreautilityspends,themoreitcancharge.

4.Thecompanyalsoaskedforandreceivedapprovalforadditionalfundstotalingabout$30billion(2.4trillionyen)tocompensatethevictimsofthenuclearaccident.(ItwasthethirdtimeTEPCOhadcomebackformoremoneytohelpvictims.)

5.Onebrightspotwasthatevenwiththeincreaseintheuseoffossilfuels,JapanwasstillontracktomeetitscarbonemissionreductiontargetsundertheKyotoProtocol.

6. The task force inadvertently sabotagedRecommendation 1 by its verywording: “TheTask Forcerecommendsestablishingalogical,systematic,andcoherentregulatoryframeworkforadequateprotectionthat appropriately balance defense-in-depth and risk considerations.” A commissioner agreeing withRecommendation1couldbeviewedas implicitly conceding that the agencyhad long takenan illogical,chaotic, and incoherent approach to protecting American lives. Had the task force phrased thisrecommendationmoreadroitly,itmighthavefaredbetter.

7.Here’sasimpleillustrationofthispoint.Currentprobabilityriskassessmentsdonottakeintoaccountthe possibility that an accident at one reactor will trigger an accident in an adjacent unit. So a safetyimprovement thatwould reduce the risk of this happening by 50 percent—say, by controlling hydrogenexplosionsinthereactorbuildingofaMarkIBWRsothatdebriscouldnotdamagesafetyequipmentataneighboringreactor—wouldregisterashavingzerobenefitinthecost-benefitcalculation.Therewouldbenobenefitbecausetheriskwasn’tincludedinthefirstplace:50percentofzeroisstillzero.

8.Spentfuelpoolstypicallydonothaveanydrainsorpipingconnectionsbelowthenormalsurfaceofthewatertoprotectagainstinadvertentdrainage.Waterinaspentfuelpoolflowsintoscuppers—similartothoseinmanyswimmingpools—thatchannelitintocollectiontanks.Pumpsdrawwaterfromthecollectiontanksandrouteitthroughheatexchangersandfilterdemineralizerunits.Thecooledandcleanedwaterispouredbackintothepoolsfromabove.Acommonarrangementmonitorsthelevelandtemperatureofthewaterinthecollectiontank—notinthepoolitself.Whenthecoolingsystemisoperating,thetankandpoolconditionsmatch.But ifcooling is impairedor lost, the tankandpoolconditionscanbevastlydifferent.TheNRC’sorder requiredoperators toprovidea reliableandaccuratemeans tomonitor the levelof thewaterinsidethespentfuelpoolundercertainaccidentconditions.

9.ThetaskforcetimelinesthemselvesdidnottakeintoaccountwhatactuallyhappenedatFukushimaDaiichi.ThereittookworkersfifteenhourstobeginemergencycoolantinjectionintotheUnit1core,bywhichtimethecorehadalreadymelted.Eveniftheinstalledcoolantsystemshadworkedforeighthours,theywouldnothavesufficedtopreventameltdown.Inshort,iftheorderhadbeeninplaceatFukushima,itwouldhaveprovidednoguaranteethatdisastercouldhavebeenaverted.

10. The call to phase out nuclear power placed some of Japan’s largest industries in an awkwardposition.MitsubishiHeavyIndustries,Toshiba,andHitachiareamongtheworld’sleadingmanufacturersofnuclearpowercomponents.Marketingtechnologyabroadthatwasdeemedunacceptablyriskyathomemight have proven difficult. TheU.S. nuclear industry also had a vested interest in the outcome of thephaseoutdebate.Since2007,GeneralElectricandHitachihavebeenbusinesspartners. In2006,ToshibapurchasedWestinghouse Electric Company. Japanese media carried reports that additional, unidentifiedU.S.interestswerelobbyingtoinfluenceTokyotoretainitsnucleargeneratingcommitment.

12.ARapidlyClosingWindowofOpportunityDocuments utilized in this chapter include Forging a New Nuclear Safety Construct prepared for theAmericanSocietyofMechanicalEngineersPresidentialTaskForceonResponsetoJapanNuclearPowerPlant Events (New York: American Society of Mechanical Engineers, 2012),files.asme.org/asmeorg/Publications/32419.pdf; the NRC’s “Briefing on the Task Force Review of NRCProcesses and Regulations Following the Events in Japan: Transcript of Proceedings,” July 28, 2011,www.nrc.gov/japan/20110728.pdf; as well as hearing transcripts from the Senate Committee on Energyand Natural Resources, Subject S. 512, the Nuclear Power 2021 Act, June 7, 2011,

www.energy.senate.gov/public/index.cfm/hearings-and-business-meetings?ID=237c8727-802a-23ad-41f3-e4cfc52bc3a2.

1.SenatorFrankencouldnotbefaultedforbeingunawareofthisdanger,fortheNRC,citingsecurityconcerns, had concealed the agency’s growingworry about the threat frompublic view formore than adecade.

2. For example, the industry adopted, and the NRC approved, this less-than-helpful standard forprotection of FLEX equipment from high temperatures: “the equipment should be maintained at atemperaturewithinarangetoensureitslikelyfunctionwhencalledupon.”

3. In itscomprehensive2102reporton theFukushimaaccident, theAmericanSocietyofMechanicalEngineers,aprofessionalengineeringsocietywithmorethan127,000membersin140countries,notedthatprotectingthepublicfromthehealtheffectsofradiologicalreleases“continuestobetheprimaryfocusofnuclearsafety.”InthecaseofFukushima,radiationreleaseswerelowandnotbelievedtoposeasignificanthealth threat. But the report identified long-lasting harm of another type: “The major consequences ofsevereaccidentsatnuclearplantshavebeensocio-politicalandeconomicdisruptions inflictingenormouscosttosociety.”Thosecosts,longoverlooked,nowalsomustbefactoredintorisk/benefitequations,theASMEconcluded.

Appendix

MaterialforthissectionwasdrawnprimarilyfromoralpresentationsandtheproceedingsoftheAmericanNuclear Society’s International Meeting on Severe Accident Assessment and Management: LessonsLearnedfromFukushimaDaiichi,SanDiego,California,November11–15,2012.

INDEX

Pagenumbersinitalicrefertoillustrations.

Abe,Shinzo,50,243,277accidentmanagement(AM)measures,16,202–3,235,245accidentsimulation.SeecomputersimulationandmodelsActonSpecialMeasuresConcerningNuclearEmergencyPreparedness(Japan),16,38acuteradiationsyndrome,27,190,192,208,215,219“adequateprotection,”187,188,190,194–95,197,234,238,257,261;NTTFon,252,253,260AdvisoryCommitteeonReactorSafeguards,153,197–98,214,218,269aerialmonitoringandmitigation,69,84,90,95–96,97,123agriculture.SeefarmersandfarmingAlaska,99,113,114,128,129,138Amano,Yukiya,105,277AmbassadorRoos.SeeRoos,JohnV.AmericanEmbassy,Tokyo.SeeU.S.Embassy,TokyoAmericanNuclearSociety,2012meeting,263–65AmericanPhysicalSociety,190,205–6Americans:helpfulhints,101–2;inJapan,62,68–69,84–85,87–89,92–93,108,129,132,134,138–39,

282n4;opinionofnuclearpower,146.SeealsoevacuationofAmericans;travelers,AmericanAmericanSocietyofMechanicalEngineers,290–91n3americium-241,128antinuclearmovement,110,146,161,205,209–10,211,228Aoki,Steven,138,277Apostolakis,George,182,183,277Areva,102,164,245AsahiShimbun,35,47,228,229,240Asseltine,JamesK.,193–94,201,278AtomicEnergyAct,187,193,194AtomicEnergyCommission(AEC),39,153,187,192,273AtomicEnergyCommissionofJapan,77,101AtomicIndustrialForum,189attitudes,complacent.Seecomplacencyandoverconfidenceauxiliarysystems.Seebackupsystems

Babcock&Wilcox,142backfitting,15,191–200,234,241,254,255,259,268;definition,287n2

backupgenerators,8,10,12,53,167,271;inFLEXplan,173,237,238;malfunction/inoperability,13,22,24,42,250–51,282n6;U.S.use,175–76,217

backupsystems,8,10,175–76,214,255;battery-operated,12,13,17,18,65,66;destroyedbytsunami,250;failure,13,65,188,218–19,248.Seealsobackupgenerators;B.5.bequipment/measures;“defense-in-depth”;emergencycoolingsystems;FLEXprogram;isolationcondensers

bailouts,178–79,228,289n4Barrasso,John,182,185batteries,12,18,19,30,31,67,74;assumptionsabout,237,251;failure,13,65,218;NRCviews,167Beasley,Benjamin,116BechtelCorporation,98,100Beck,Glenn,102Bernero,Robert,190,208“best-estimate”scenarios,130,139,212,213beyond-design-basisaccidents,14,153,167,169,173,188,234,235,237,269;assumptionsabout,viii,16,

140;NRCviews,195,202,206,208,253;planningfor,20,169–70,188–91,199–203,218,236,237,252,253;Virginia,175–76.SeealsoChernobylnuclearaccident,1986;severeaccidentmanagementguidelines(SAMGs);severeaccidentmitigationalternatives(SAMA);ThreeMileIslandnuclearaccident,1979;Tokaimuraresearchcenter:nuclearaccident,1999

B.5.bequipment/measures,95,169,173,215,218,235,269,285n4blackouts.Seepoweroutagesboilingwaterreactors(BWR),5–6,6,70–71,77,84,245,269.Seealsocoolingsystems;MarkI

containment;MarkIIcontainment;MarkIIIcontainmentBonaccorso,Amy,101–2Borchardt,Bill,65,86,89–90,91,94,139,232–33,278boronandboricacid,62,88,98,283n2Boxer,Barbara,94,95,182Bradford,Peter,258breederreactors,171,286Brenner,Eliot,114,116,278Bromet,Evelyn,111BrownsFerryNuclearPowerPlant,248,249,250,261Burnell,Scott,112,116,278Burns,Shawn,217–18

California,94,134,139,164,182.SeealsoDiabloCanyonPowerStation;SanOnofreNuclearGeneratingStation

cameras,remote,12,32,90,97,266cancer,27–28,84,108;AECriskstudy,192;CRAC2quantification,207,208,216,219;IDCOR

projections,190;NUREG-1738study,211;SOARCAprojections,213,216,219,220;Yoshida’s,284n1

Candris,Aris,245,246Carney,Jay,92Casto,Charles“Chuck”,86–90,86,93,95–101,124–25,131–35,155,163,278;attire,284–85n2;

shortchangedbyOfficeofResearch,285n3;speechatRIC,260–61casualties.SeefatalitiesCenterforResponsivePolitics,287n1cesium,60,62,82,118,146,155,156,156,268;infood,178cesium-134,159cesium-137,71,97,126–27,157,159,164,211,267,288n9;aerialmeasuring,97;infood,157Chernobylnuclearaccident,1986,20,44,45–46,100,104,130,164,202,209,249,261;casualties,27,90;

consideredirrelevant,201,205;Fukushimacompared,268,272;INESrating,104;mentalhealthaspects,111;mitigation,90,100;permanentexclusionzone,178;populationresettlement,164–65

children,58,89,109,109,139,161,162,178,179,223;Alaska,129;CaliforniaandWestCoast(U.S.),134,139;cancerrisk,28;evacuees,120,148,160,241,242

China,25,38,44,100,124,160,171ChubuElectric,41,170CitizenScientist(vonHippel),192Citizens’NuclearInformationCenter,106cladding,5,6,7,57,66,127;ignitionof,57,71,82,91,113,127,145;ThreeMileIsland,14,145classifiedinformation,209,211cleanup,157,159,163,164,177–78,179;bycitizens,162;inCRAC2modeling,207;ThreeMileIsland,

146,164cleanupcosts,84,165,177–78,179,214,226,254,289n4;ASMEon,290–91n3;CRAC2model,207;

ThreeMileIsland,146,164cobalt,155coldshutdown,62,163,180,222,269ColdWar,38,39,207common-modefailure,250,269communications,16,17,22,25,26,76–77,86,87;bungled,21,76;e-mail,35–36,46,54,101,112,115–

16,185,217,220;intra-industry,151;Japanesegovernment,23,26,59,103,104–5,108–9,157;phone,17,148;ThreeMileIsland,145,147,148;video,25,86.Seealsoinformationsharing;informationwithholding;media;pressconferences;pressreleases;publicrelations;secrecy

companyuniforms,23,67,285n1compensationtovictims,165,178–79,226complacencyandoverconfidence:fosteredbydefense-in-depthapproach,250;Franken’s,247–48;

Japanese,12,16,44,225,226;notedafterThreeMileIslandaccident,150;NRC,167,168,185–86,200–201,203,208,216,221;inplantdesignandsiting,51;inreactordesign,70

computersimulationandmodeling,14,79,125,136,218;Castoview,87–88;Exelon,135;failuretoexplainFukushimaevents,viii,263,264;NARAC,126;post–ThreeMileIsland,189;ofradioactiveexposure,99;forSOARCA,212,215;byTEPCO,179.SeealsoCRAC2study;MELCOR;RASCAL(RadiologicalAssessmentSystemforConsequenceAnalysis)

concrete,5–6,7,14,70,75,113,122,123,136,145–46,180,188;reactionwithmoltenfuel,7,179–80,264;instoragecasks,7,83

conflictofinterest,46Congress.SeeU.S.Congressconsumerelectricityrates.Seeelectricityratescontaminatedfood.Seefoodcontaminationcontaminatedhomes,206,207,220,230.Seealsoevacuationofresidentscontaminatedmaterials,disposalandstorageof.Seedisposalandstorageofcontaminatedmaterialscontaminatedsoil.Seesoilcontaminationcontaminatedwater.Seeradioactivewatercontaminationlevels.Seeradiationlevelscontrolrods,5,49,269–70,282n2,283n2controlrooms,5,8,49,142,150;blackouts,13,17–20,25,74,124;BrownsFerry,248;communications,

9,17,147–48;evacuation,75,85;radiationlevels,29,85;remoteoperationsfrom,19–20,25,31,32,66,241,284n7;secondary,241;stresslevelin,144;ThreeMileIsland,144,147–48,157;Units1and2,13,17,18,19,22,25,29,29,31,32,124;Units3and4,17–18,66,67,73

coolingsystems,7–8,12,70,84,94,98,142,164,184,218,248,250;effectondesign,51;ThreeMileIsland,142–47.Seealsoemergencycooling;spentfuelpools

“corecatchers,”188,245

coremeltdowns.Seemeltdownscorruptionandcollusion,46,47,48cost-benefitanalysis,191–92,193,195,196,234,256,259,268,289n7;definition,270;Fitzpatricknuclear

plant,198;of“recombiners,”202;terroristattacksexcludedfrom,209costofcleanup.Seecleanupcostscostofhumanlife.Seefatalities;humanlife,monetaryvaluecoverallsanduniforms,23,67,285n1.Seealsoprotectiveclothingcover-ups,48,184,206–8CRAC2study,207–9,211,212,214,215,216,219,220Cuomo,Andrew,116Curran,Diane,194Curtiss,James,198

dairyindustry.SeemilkcontaminationDaley,William,177damfailure,183–85,248Davis-BesseNuclearPowerStation,143–44,151,289n2deaths.SeefatalitiesDCpower,8,32,167,237,282n3;definition,270;lossof,13,17,26,167,202.Seealsobatteriesdecayheat,7,65,189,270decontamination.SeecleanupDedman,Bill,115–17,278DeepwaterHorizonoilspill,2010,102DefenseDepartment.SeeU.S.DepartmentofDefense“defense-in-depth,”196,248–51,252,253,254,255,257,270,289n6DefenseThreatReductionAgency,97demonstrations.SeeprotestsDenton,Harold,101–2,148,149DepartmentofDefense.SeeU.S.DepartmentofDefenseDepartmentofEnergy(DOE).SeeU.S.DepartmentofEnergy(DOE)DepartmentofHomelandSecurity.SeeU.S.DepartmentofHomelandSecurityDepartmentofState.SeeU.S.DepartmentofStatedesign-basis,169,173,184,270design-basisaccidents,13,14,115,144,153,187,188DiabloCanyonPowerStation,34,98,115,128dieselgenerators,8,10,53,167,168,169,214,250,271;confidencein,12,168,282n6;

malfunction/inoperability,10,22,250–51,282n6;U.S.emergencyuse,175–76,249dieselpumps,19,66,95,169,214directcurrent.SeeDCpowerdirt,91,160,162.Seealsosoilcontaminationdisasters.Seeearthquakes;floods;tsunamisdisease,27–28.Seealsocancerdisposalandstorageofcontaminatedmaterials,163,164,243DNAdamage,27,28Dominion,176Donald,Kirkland,68,89,278Dorman,Daniel,54,87,99,278doserates.Seeradiationlevelsdosimeters,22,59,85,270drills,emergency.Seeemergencyexercises

droneuse,69,97drycaskstorage,83–4,211,256,270drywell,5–6,55,270–71;breachof,26,28,57,264;Unit1,25,26,28,57;Unit2,74,267;Unit3,69DukeEnergy,185Dyer,Jim,139

EarthquakeCountermeasuresAct(Japan).SeeLarge-ScaleEarthquakeCountermeasuresAct(Japan)earthquakes,1–5,9–10,41,47–48,51,94,95,246;aftershocks,29,30,73,85;assumptionsabout,53,213,

214;consequencesforeseen,211,217–18,245;early-warningsystems/detection,1,3–4,114–15;effectonpipes,seals,etc.,159;forecasting,42–43,44,52,229;Frankenjokeabout,247;magnitudescales,281–82n1;Niigata,2007,19,42,50,225;planningfor,63,169,170–71,201;Sanriku,1896,9–10,52,54;shutdownafter,5,114–15;spentfuelpoolsand,71;UnitedStates,113,114,175–76,249–50,253,287n6.SeealsoJoganearthquake;TohokuEarthquake,2011

economiccosts.Seebailouts;cleanupcostsTheEconomist,178–79,227Edano,Yukio,23,26,59,96,103,104,104,108,109,165,277;downplaysfoodcontamination,157;as

ministerofEconomy,TradeandIndustry,179,226–27,231,240;on-cameradress,285n1,EducationMinistry.SeeMinistryofEducation,Culture,Sports,ScienceandTechnology(MEXT)elections,15,240,243electricalcables,13,19,24,57,124,158,248electricalgridincompatibility,282–83n8electricaloutages.Seepoweroutageselectricityuseandsupply(electricalgrid),38,171–72,205,224,227,228–29;rates,179,227,289n3.See

alsoelectricalgridincompatibilityElectricPowerResearchInstitute,102emergencybackupsystems.Seebackupsystemsemergencycooling,8,13,14,33,49,69,72,93,131,167,251,290n9;“feedandbleed,”158,163,271;

FLEXplan,173,174,254,256;innewreactordesigns,244,245;policyrecommendations,168–69;Unit1,17,19,25,33,60–61,122;Unit2,17,97,122;Unit3,65,66,122;U.S.involvement/proposals,98,100,101,189,197,199,255–56;vulnerability,180.Seealsoemergencycorecoolingsystems;fireengines,pumps,etc.;seawater:emergencyuse

emergencycorecoolingsystems,8,17,187,241,271;BrownsFerry,248;failure/lossof,18,49.Seealsohigh-pressurecoolantinjectionsystem(HPCI);reactorcoreisolationcoolingsystems(RCIC)

emergencyevacuation.SeeevacuationofAmericans;evacuationofresidents;evacuationofworkersemergencyexercises,25,62,78,142,152,287n4emergencygenerators.Seebackupgeneratorsemergencyplanningzone,129,140,215–16,221,256,271emergencyproceduresmanuals.Seemanualsemergencysystems.Seebackupsystemsemergencyworkers,22,85,93,106,181,243;vulnerability,94,158,284n8energyconsumption.SeeelectricityuseandsupplyEnergyDepartment.SeeU.S.DepartmentofEnergy(DOE)energypolicy,Japanese,47,108,165,171–72,222–23,227,231,239–40EnergyPolicyAct(EPAct),204–5EnvironmentalProtectionAgency.SeeU.S.EnvironmentalProtectionAgency(EPA)equipment,backup.Seebackupsystemsequipmentupgrades.SeeretrofittingEuropeanUnion,224.SeealsoFinland;France;Germany;SwedenevacuationofAmericans,84–85,87,88–89,92,108,129,132,134,138–39evacuationofresidents,16,24,30,31,37,57–59,77,117–20,117,160–61,241–43,285n2;Chernobyl,46;

compensationfor,165,178–79,207,226,289n4;computermodeling,80,87,207,215–16;housingandservices,117,157,160,178;long-termstatus,230;simulations/exercises,152;statistics,45;ThreeMileIsland,141,148–49.Seealsoevacuationzones

evacuationofworkers,12,76evacuationzones,77,108,117,120,140,159,241,256;initialexpansionof,30;maps,119,242;media

steersclearof,105–6;NRCrecommendations,80,87,90,92–93,99,139–40;radiationlevels,178;ThreeMileIsland,148;U.S.regulations,190

ExelonCorporation,61,102,135,174,236–39exhauststacks,4,32,57,67,266explosions:Chernobyl,46;effectonpipes,seals,etc.,159;Unit1,32,54,55–57,56,61–62,71,93,122;

Unit2,74–75,78,98;Unit3,72,72,81,118,265;Unit4,75–76,75,80–82,88,91.Seealsohydrogenexplosions

exposuretoradiation.Seeradiationexposure

failure,common-mode.Seecommon-modefailurefallout,99,114,118,156,159.Seealsocleanupfalsificationofreports,46,48–49,50farmersandfarming,119,120,157fatalities:cattle,120;Chernobyl,27,90;CRAC2projections,207,208,209,215;afterearthquake/tsunami,

9,10,43,118,181;HiroshimaandNagasakibombings,39;“latent”(fromcancer,etc.),28,84,190,192,207,208,211,213,216,219,220,256;NUREG-1738projections,211;riskassessment,192;Tokaimura,37

faultlines,41,42,44,50,52,170,229fears,public.SeepublicfearsFederalEmergencyManagementAgency,152Fertel,Marvin,232filtersandfiltering,17,28,267;incleanup,164;ventilation,20,128,188,231,241,254–55,268;ofwater,

60,289n8;waterusedfor,28,74Finland,189fireengines,pumps,etc.,19,77,100,124,131,202,265;damageto,72;inadequacy,29,30,97;Unit1,19,

30,33,57,62,65;Unit2,73,74;Unit3,66,69,96,97,121,122;Unit4,136;U.S.,97fires,50,71,87,91,211;BrownsFerry,248,250;possibility/threatof,167,173,217,248;protectionfrom,

239;Unit3,99;Unit4,81–82,133fishingindustry,156fission,5,7,46,269–70fissionproducts,7,57,66,70,109,126–27,187,189,267FitzPatricknuclearplant.SeeJamesA.FitzPatrickNuclearPowerPlantFLEXprogram,173–74,236–39,254–55,256,259,271,290n2flooding,167,169,238;assumptionsabout,214,217–18,238;incomputermodels,219;afterdamfailures,

183,184,248;Fukushima,10,13,124,137,141,159;UnitedStates,174,175,176,249floodwalls,185.SeealsoseawallsFlorida,249foodcontamination,127,129,139,156,157,178,207foreignrelations,Japanese,125,131,160FortCalhounNuclearGenerationStation,174,175,176,249,250France,102,125,164,245,247Franken,Al,247,290n1freshwater,286n2;emergencyuse,30,33,57,67,135,137;normaluse,60,131fuelassemblies,5,48,57,70,83,84,266,271FukuiPrefecture,224,230

FukushimaDaiichidesignandconstruction,5–6,7,8,51,52,53–54.SeealsoSeismicIsolationBuilding;MarkIcontainment;spentfuelpools

FukushimaDaininuclearplant,18,40,282n7FukushimaPrefecture,10,16,24,40,52,105,156,157,178,181,253;contaminationlevels,163;schools,

160,161,162Futaba,Japan,16,24,40,118

gammarays,127gas,natural.Seenaturalgasgases.Seehydrogen;nitrogen;radioactivegasesgauges,19,23–24,65,74,81,150;calibrationinsufficiency,263–64;jury-rigged,55;lacking,144GEHitachiNuclearEnergy,87,135,290;ESBWR,114,245GeneralElectricCorporation(GE),5,14,39,40,87,244,245,290n10;collaboration,102,132;employees,

48.SeealsoMarkIcontainment;MarkIIcontainment;MarkIIIcontainment.SeealsoGEHitachiNuclearEnergy

GeneralPublicUtilitiesCorporation,148generators.Seebackupgenerators;dieselgenerators;portablegenerators;turbinegeneratorsGermany,124,282n8golfcourses,179Goto,Masashi,225governmentbailouts.SeebailoutsGreatTohokuEarthquake.SeeTohokuEarthquake,2011groundmotion,1,3,44,50,114–15,175Grobe,Jack,77–78,84–85,278

Hachiro,Yoshio,179half-life,127Hamaokanuclearplant,41–42,44,170,229hardenedvents,63,203,268,272,283n4;incorporatedatFukushima,169,202;NRCviewsandactions,

197,198–99,235,254Hardies,Robert,54Harrisburg,Pennsylvania,141,146,147,148Hashimoto,Toru,230,231,277Hatamura,Yotaro,108,226,277hazmatsuits.SeeprotectiveclothingHeadquartersforEarthquakeResearchPromotion,44,52healthconsequences,27–28,108,127,158,219;mentalhealth,111;NRCviews,205,211,213,216,219;

projectedbyCRAC2,206,207.SeealsocancerHearn,Lafcadio,282n4heatsink,7,236,272Hein,LauraE.,38helicopters,1,21,30;mitigationfrom,83,90,95,96–97,99,121,123–24,136,137;radiationon,68Hendrie,Joseph,145,187high-pressurecoolantinjectionsystem(HPCI),65–66,69,264,265,272Hirose,Naomi,228,277Hiroshimabombing,1945,27–28,49Hitachi-GEpartnership.SeeGEHitachiNuclearEnergyHolahan,Trish,129,130–31HomelandSecurityDepartment.SeeU.S.DepartmentofHomelandSecurityhomes,contaminationof.Seecontaminatedhomes

Hosono,Goshi,177–78,277HPCI.Seehigh-pressurecoolantinjectionsystem(HPCI)HudsonRiverkeeper,209humanerror,94,133–34,140,142–43,225;Futaba,118;Sandiaview,217;ThreeMileIsland,45,142–43,

149–50,188humanlife,monetaryvalue,193hurricanes,94,249,253hydrogen,7,28,57,66,74,91,145,188,200,264,265,287n5hydrogenexplosions,14–15,56,61–62,71,75–76,80–82,91,122,219,266;attemptstoexplain,264;

positivesideeffects,84,266;prevention,15,55,195,200,202;ThreeMileIsland,141,145,188,195

IAEA.SeeInternationalAtomicEnergyAgency(IAEA)IDCOR.SeeIndustrialDegradedCoreRulemakingprogram(IDCOR)Iitate,Japan,118–20,160,267importedfuelreliance,171,228–29IndianOceanearthquake,2004,44,47IndianPointEnergyCenter,115–16,208,209,214,287n6,288n2IndividualPlantExamination(IPE)program,191,199IndustryDegradedCoreRulemakingprogram(IDCOR),189–90,196,205industrymeasures,voluntary.Seevoluntaryindustrymeasures“inerting,”15,55,195,200,202INES.SeeInternationalNuclearandRadiologicalEventScale(INES)informationsharing,35,62,69,87,96,151,155.Seealsopublicdisclosureandparticipationinformationwithholding,58,107,108,109,118,151–52,216.Seealsoclassifiedinformation;cover-ups;

secrecyIno,Hiromitsu,225inspections.SeenuclearplantinspectionsInstituteofNuclearPowerOperations(INPO),61,102,131,151–52instrumentscaleproblems,144–45,158,263–64insubordination,60–61,86InternationalAtomicEnergyAgency(IAEA),22,50,105,119,224–25,228,268InternationalCommissiononRadiologicalProtection,161InternationalNuclearandRadiologicalEventScale(INES),22,103–4,109–10,272Internet,12,35,106–7,109,110InvestigationCommitteeontheAccidentattheFukushimaNuclearPowerStations,108,226iodine,62,118,125,140,146,155,157,256.Seealsopotassiumiodideiodine-131,71,126–27,133,146,267–68,288n9;inCalifornia,128;inmilk,157;inseawater,156;Unit2,

159,267;Unit3,158;Unit4,133IPEprogram.SeeIndividualPlantExamination(IPE)programirradiatedfuel.SeespentnuclearfuelIshibashi,Katsuhiko,41,42,48,277isolationcondensers,8,13,17,18,22,25,264,282n3

Jaczko,Gregory:adherencetoscript,114;atcongressionalhearings,92,182,183;eventmonitoring(days2–4),54,61,62–64,77;eventmonitoring(days5–8),79,84–85,89–90,92,93–94,95,96,113,114;eventmonitoring(days9–10),130–31,138;managementstyleandresignation,176–77,233;mandateforrecovery,166;atoddswithfellowcommissionersandNRCstaff,172–73,176–77,212,232–33,245,288n1;onworst-casescenarios,130

JamesA.FitzPatricknuclearplant,198–99JapanAtomicEnergyCommission.SeeAtomicEnergyCommissionofJapan

JapanDefenseMinistry.SeeMinistryofDefenseJapanEducationMinistry.SeeMinistryofEducation,Culture,Sports,ScienceandTechnology(MEXT)JapaneseDietIndependentInvestigationCommission,244–45JapaneseEmbassy,Washington,DC,131Japaneseenergypolicy.Seeenergypolicy,JapaneseJapaneseforeignrelations.Seeforeignrelations,JapaneseJapanesenuclearplantlicensing.SeelicensingofJapanesenuclearplantsJapanesenuclearplants.SeeFukushimaDaininuclearplant;Hamaokanuclearplant;Kashiwazaki-Kariwa

nuclearplant;Monjunuclearplant;OhinuclearplantJapanMeteorologicalAgency,1,3,4,15,281n1JapanMinistryofDefense.SeeMinistryofDefenseJapanMinistryofEconomy,TradeandIndustry(METI).SeeMinistryofEconomy,TradeandIndustry

(METI)JapanMinistryofEducation.SeeMinistryofEducation,Culture,Sports,ScienceandTechnology(MEXT)JapanNuclearEnergySafetyOrganization,16JapanNuclearSafetyCommission.SeeNuclearSafetyCommission(NSC)JapanScienceandTechnologyAgency,37,38JapanSelf-DefenseForces.SeeSelf-DefenseForces(SDF)JapanSocietyofCivilEngineers,52JapanTimes,171JCOCompany,37JocasseeDam,184,185Joganearthquake,9–10,52,54JustificationforContinuedOperation,185

Kaieda,Banri,26,30,277Kammerer,Annie,115,116,278Kan,Naoto,15,225,277;callsfornuclearphaseout,171–72;disasterresponse,17,22–26,23,30–31,37,

55,59–61;duringearthquake,1,15;informationwithheldfrom,58;NSCrelations,109;orderstoresidents,30,76;post-disaster,23,26,170–72,224,240,285n5;Shimizurelations,67,76–77,243;U.S.relations,95,96

KansaiElectricPowerCompany,230Kashiwazaki-Kariwanuclearplant,18,19,42,49,50,225,228,239,283n2Katsumata,Tsunehisa,21,50,226,277Keidanren,240Kemeny,JohnG.,150KemenyCommission,147,149,150,186Kennedy,RobertF.,Jr.,209Kobeearthquake,1995,3,44,47Kosako,Toshiso,162,277krypton-85,146Kurion,164KyotoProtocol,289n5

landcontamination.SeesoilcontaminationLarge-ScaleEarthquakeCountermeasuresAct(Japan),42,43lawsuits,41–42,179,194liabilityprotection,246licensingofJapanesenuclearplants,42,44licensingofU.S.nuclearplants,111,113–14,170,175,184,205;amendments,198,287n3;FortCalhoun,

175;renewal,259;Vogtle,245,288n1LimerickNuclearPowerPlant,214linearno-thresholdhypothesis(LNT),216lobbying,36,94,287n1,290n10Lochbaum,David,201,283n1Luxat,David,264Lyman,Edwin,94,95,288n3

Macfarlane,Allison,176,177,278Madarame,Haruki,31,41–42,47,55,59,60,109,225,277Magwood,William,182,183,278manualoperations,20,25,28–29,31,66,201,251,284n7manuals,20,251maps,2,45,98,119,126,242Markey,Edward,206,208,212,214MarkIboilingwaterreactor,40,204MarkIcontainment,5–6,6,15,63,70–71,87–88,186,195–200,244,289n7;dilemmas,195;atPeach

Bottom,213,237;retrofitting,202,235,254;ventilation,19–20,169,235,268MarkIIcontainment,15,70–71,169,200;retrofitting,202,235,254,268;ventilation,235,268MarkIIIcontainment,200,287n5McDermott,Brian,64,79McGaffigan,Edward,209–10,210,211,217media,26,34,35,58,106,112;antinuclearviews,171;Japan,1,46,47,58,59,67,105–7,110,111,171,

229,241;McGaffiganviewof,210;NRCrelianceon,54,61,84,85,136;UnitedStates,64,85,111–16,119,146–48,180–81,214,286n1;oncontamination,178.Seealsopressconferences;pressreleases;television

Mehta,Zubin,100MELCOR,139,140,264,272,286n3meltdown,7,12,78,79,82,89,179–80,264,290n9;assumptionsabout,130,132,187–88;design

anticipating,188,245;fearsof,136;governmentbelatedacknowledgmentof,109–10;notconsideredinplanning,71,239;NRCanalysis,195–96;NRCpublicrelationsview,113;prevention,20,153,197,218;radionuclidereleaseduring,127–28;terrorist-caused(hypothetical),209,211;ThreeMileIsland,45,141,145,147;Unit1,22,24,30,55,59–60,62,64;Unit2,78;Unit3,66;Unit4,82

meltdown(word),60,272mentalhealth,111Meserve,Richard,226,289n2MetropolitanEdison,142,147–48micromanagement,25,212Middletown,Pennsylvania,146–47military.SeeSelf-DefenseForces(SDF);U.S.militarymilkcontamination,129,139,157Miller,CharlesR.“Charlie”,64,90,138,139,169,278Milne,John,42–43Minamisoma,Japan,106–7MinistryofDefense,132MinistryofEconomy,TradeandIndustry(METI),15,16,22,26,30,100,110,161MinistryofEducation,Culture,Sports,ScienceandTechnology(MEXT),15,16,58–59,178Minnesota,247–48MissouriRiverflooding,2011,174,175,176modularreactors,205,245–46

Mogi,Kiyoo,43–44,277momentmagnitudescale,281–82n1Monjunuclearplant,286n1Monninger,John,88,90–91,95,100,125,135,136–37,278monopolies,38,227Mullen,Mike,129–30,278Murray,ThomasE.,39

Nagasakibombing,1945,27–28,39Nakamura,Koichiro,59,277Namie,Japan,57–58,59,118NationalAtmosphericReleaseAdvisoryCenter(NARAC),126,129,130,132,133–34,137–38,139,268NationalEnvironmentalPolicyAct,259NationalGeographic,282n4NationalNuclearSecurityAdministration,68,69,97NationalOceanicandAtmosphericAdministration,34NationalSeismicHazardsMaps,44naturaldisasters.Seeearthquakes;floods;tsunamisnaturalgas,205,228–29Nature,38NavalReactors.SeeU.S.DepartmentofEnergy(DOE):OfficeofNavalReactorsNBCNews,115–17NEI.SeeNuclearEnergyInstitute(NEI)newmedia,106–7newsconferences.Seepressconferencesnewsmedia.SeemediaNewYorknuclearplants,40,115–16,190,198–99,208,209,214,287n6,288n2NewYorkStatePowerAuthority,198NHK(televisionnetwork),1,12,32,97Niigataearthquake,2007,19,42,50,2259/11terroristattacks.SeeSeptember11,2001,terroristattacks(9/11)NineMilePointnuclearplant,40NISA.SeeNuclearandIndustrialSafetyAgency(NISA)Nishizawa,Toshio,166,277nitrogen,15,55,195,200,202Noda,Yoshihiko,172,179,180,222–23,224,229,231,240,243,277NorthAnnaPowerStation,175–76,249–50NRC.SeeNuclearRegulatoryCommission(NRC)NuclearAccidentIndependentInvestigationCommission,111,277nuclearaccidents.Seedesign-basisaccidents;beyond-design-basisaccidents;Chernobylnuclearaccident;

ThreeMileIslandnuclearaccident;Tokaimuraresearchcenter:nuclearaccidentNuclearandIndustrialSafetyAgency(NISA),15,16–17,22,38,49,82,229,241;communications,25,26,

58,59–60,100,103;encouragesuseofshills,46;hearingsonearthquakeandtsunamihazards,53–54;INESrankingby,103;protestsagainst,222,224;restartapproval,224,225,229;TEPCOrelations,51,76;U.S.relations,78,84,97,98,100

NuclearEmergencyPreparednessAct(Japan).SeeActonSpecialMeasuresConcerningNuclearEmergencyPreparedness(Japan)

NuclearEnergyInstitute(NEI),94,136,196,200,205,209;lobbyingexpenditures,287n1;NRCrelations,116,129,232;predecessor,189;SOARCAinvolvement,212–13;writesownrules,235,236,238,239

nuclearfission.Seefission

nuclearfuel,5;cooling,7,8,18,158;damage,56,62,71,103,126,127–28,145,158;hydrogengeneration,7,56,145;reprocessing,240;rods,5,7,145;supply,171.Seealsofuelassemblies;drycaskstorage;meltdown;spentfuelpools

NuclearInformationandResourceService,256nuclearplantdefense-in-depthapproach.See“defense-in-depth”nuclearplantinspections,260,266;IAEA,50,119;Japan,16,17,48,49,51,170,223;NRC,152,173,

175,199,218,235–36,252,253,287nn4–5,289n2;byplantowners,191;precludedbyhighradiation,180

nuclearplantlicensing.SeelicensingofJapanesenuclearplants;licensingofU.S.nuclearplantsnuclearplantsafetyreportsandrankings,116,152nuclearplants,European,224.SeealsoChernobylnuclearaccident,1986nuclearplantshutdown,151,201,275;inemergency,5,7,114–15;Hamaoka,170;Japan-wide,171–72,

222–24,240,ThreeMileIsland,142,144.Seealsocoldshutdown;restartofreactorsnuclearplantsitingandconstruction,40–41,42,43,44,153nuclearplants,Japanese.SeeFukushimaDaininuclearplant;Hamaokanuclearplant;Kashiwazaki-Kariwa

nuclearplant;licensingofJapanesenuclearplants;Monjunuclearplant;Ohinuclearplantnuclearplants,U.S.,40,63,94,111–15,166–70,182–204,212–13,287n4;California,34,94,98,115,128;

HurricaneAndrewsurvival,249;Minnesota,247–48;neardisasters,174–76;NewYork,40,115–16,198–99,208,209,214,287n6,288n2;spentfuelstorage,83,84.SeealsoBrownsFerryNuclearPowerPlant;Davis-BesseNuclearPowerStation;OconeeNuclearStation;PeachBottomNuclearGeneratingStation;SurryNuclearPowerPlant;ThreeMileIslandNuclearGeneratingStation

nuclearreactordesign,14,41,114,176,245–46.Seealsoboilingwaterreactors(BWRs);FukushimaDaiichidesignandconstruction;modularreactors;pressurizedwaterreactors(PWRs)

NuclearRegulationAuthority(NRA),240–41NuclearRegulatoryCommission(NRC),12,15,35,173,182–203,252–61,287nn4–6;acquiescenceto

industry,236–39;AdvanceNoticeofProposedRulemaking,188–90,286–87n1;AdvisoryCommitteeonReactorSafeguards,153,197–98,214–15,216,217,218;AEOD,151;auditing,49;backfitrules,15,191–98,234,259;citizens’suggestionsto,101–2;cover-upsandinformationwithholding,206–8,213–14,219–20;CRAC2study,207–9,211,212,215,216,219,220,288nn8–9;disastermonitoringandassistance,34–37,54,61–65,77–82,84–96,98–101,124–25,129–30,131;FortCalhounrelations,175;IndividualPlantExamination(IPE)program,191,196,199;infightinganddissent,172–73,176–77,194,196,217,218,232–33;informedbyWallStreetJournal,136;Japanasksforassistance,99,131;lawsuitagainst,194;McGaffiganrole,209–10,211,288n4;MELCOR,139,140,264,272,286n3;NARACrelations,138,139;Near-TermTaskForce(NTTF),166–70,172–73,176–77,185,232–34,237,252–53,254,256,260;NUREG-1738,211;OfficeofNuclearReactorRegulation,148,218;OfficeofNuclearRegulatoryResearch,116,288n5;OfficeofNuclearSecurityandIncidentResponse,129;OfficeofResearch,212,217,285n3;performance-basedregulation,235–39;ProtectiveMeasuresTeam,62–63,79,125;publicrelations,64–65,101–2,111–16,148,209;RegulatoryInformationConference(RIC),204–6,219–20,260–61;roleineventsofU.S.radiationrelease,283–84n5;atSenatehearings,182,183,185;SevereAccidentPolicyStatement,190,195,201;State-of-the-Art-ReactorConsequenceAnalyses(SOARCA),130,204,205–6,211–21,268,288n9,289n1;ThreeMileIslandinvolvementandfollow-up,145,147–48,149,151,152,153;“vulnerabilityassessment,”209.SeealsoRASCAL(RadiologicalAssessmentSystemforConsequenceAnalysis)

NuclearSafetyCommission(NSC),15–16,31,38,41,55,59,108–9,202–3,225,229,241;corruption,47;receivesrestartrecommendations,224;rulesonstresstests,229

NuclearSufferersLifeSupportTeam,157NuclearUtilityManagement&ResourcesCouncil,196NUREG-1738,211

Obama,Barack,92,96,128–29

OconeeNuclearStation,184–85,184Ofunato,Japan,53Ohinuclearplant,224,229–31oilreliance,171,228–29oilspills,102Okuma,Japan,16,24,40,178,243OmahaPublicPowerDistrict,174,175Osaka,230,231Ostendorff,WilliamC.,173,182,183,187,233,234,278overconfidence.SeecomplacencyandoverconfidenceOysterCreekNuclearGeneratingStation,40,195

PacificOcean,7,19,33,34,60,128,133,138,159;contamination,155–56,156.SeealsoseawaterPacificPlate,2–3paperwork,49,67–68.Seealsoauditing;falsificationofreportsPardee,Charles“Chip,”174,239passivecooling,83“passive”reactorsystems,245–46PeachBottomNuclearGeneratingStation,213,214,215,216,217,218–19,220,237,288n6;Exelonplan

for,236–38Pennsylvaniagovernment,147,148Pennsylvanianuclearaccident,1979.SeeThreeMileIslandnuclearaccident,1979Pennsylvanianuclearplants.SeeLimerickNuclearPowerPlant;PeachBottomNuclearGeneratingSystem;

ThreeMileIslandNuclearGeneratingStationPietrangelo,Tony,94–95,278platetectonics,2–3plutonium,171,240plutonium-239,127,128portablegenerators,25,69,169,173,214,217potassiumiodide,129,138,139,256,273poweroutages,8,10,12–13,17,18,29,31,94,124,137,251;computersimulationsandhypothetical

scenarios,87–88,218–19,220,246,268;effectonnewstransmission,117;effectonsafetydevices,200;effectonSPEEDI,58;effectonspentfuelpools,81;planningfor,167,168,195–96,203,214,217–18,236,237;U.S.plants,175–76,185,249,282n6

PrairieIslandNuclearGeneratingPlant,247–48pregnantwomen,89,148,241President’sCommissionontheAccidentatThreeMileIsland.SeeKemenyCommissionpressconferences,26,59–60,92,109;ThreeMileIsland,149pressreleases:MetEd,147;NRC,64,80,114;TEPCO,18,22,23,103,107;U.S.Embassy,88pressurizedwaterreactors(PWRs),141,142,200,213,230,273,284n6Price-AndersonAct,246probabilisticriskassessment(PRA),192–93,201,202,208–9,213–14,234,273,287n6,289n1,289n7;

IndianPoint,288n2;mootedbyFukushima,220–21ProtectiveActionGuides(PAGs),80,274,283n3protectiveclothing,22,26,29,31,59,75,85,96,119,181;wornbyresidents,162protests,136,161,162,165–66,181,222,223–24,223,231,240;U.S.(c.1970s),146psychologicalimpact,111,207PublicCitizen,152publicdisclosureandparticipation,257–58,259,260,286–87n1,287n3.Seealsosecrecypublicfears,100,130,148,178,186,205,209,215,222;informationwithholdinginviewof,108,118,216

publichealth.Seehealthconsequencespublicopinion,Japanese,41–42,46,162,222,231,239.Seealsoprotestspublicrelations,63,64–65,101–2;Japanesegovernment,23,26,59,103,104,108–9,157;TEPCO,107–8.

SeealsoNuclearRegulatoryCommission(NRC):publicrelations;pressconferences;pressreleases

radiationdetectors,68,144–45.Seealsodosimetersradiationexposure,31,62–63,78,120,129;CRAC2on,207;doselimits,76,78,98,158,162,177;

physiologicaleffect,27–28;riskassessment,192;Unit3,158;U.S.guidelines,284n8.Seealsohealthconsequences;lethality;protectiveclothing

radiationlevels,69,85,90,91,108,122,163,177,179;aerial,69,96,99;California,128;citizenmonitoring,109;governmentadvicetopublic,104–5,162;“hotspots,”118,119,140,159,160,178;Iitate,118,160;mapping,98,124;atplantgate,26,32,82,107;atsea,68,88,155–56;southofTokyo,78;ThreeMileIsland,144–45;Unit2andenvirons,29,90,100,158;Unit3andenvirons,67,72–73,97,99,100,158;Unit4andenvirons,72,78,82;unitsofmeasure,27;U.S.monitoring,114.Seealsodosimeters;evacuationofresidents;radiationexposure:doselimits

radioactivefallout.Seefalloutradiationrelease,7,14,28,113,118,146,155–56,267–68;announcedtopublic,26;ASMEview,290–

91n3;assumptionsandforecasts,41,88,140,190,205–6,211,213,214,215,220;computermodeling,58,63,79,87,288n9;designshortcomings,17,20,58;hypothetical,71,78,219;UnitedStates,45,146,148,150,283–84n5.Seealsocleanup;publicfears;radiationdetectors;radiationexposure;sourceterm;ventilation

radiationsyndrome,acute.Seeacuteradiationsyndromeradioactivegases,5,7,32,71,74,127–28,146,266–67;scrubbing,20,267;venting,4,28,169,254radioactiveisotopes(radionuclides),126–28,155–56,207,211;releasedatThreeMileIsland,146.Seealso

cesium-137;iodine-131radioactivewater,155–56,158–59,164RASCAL(RadiologicalAssessmentSystemforConsequenceAnalysis),63,79–80,87,126,129,134,207,

274RCICsystems.Seereactorcoreisolationcoolingsystems(RCIC)reactorcontainment,5–6,14,48,70–71,128,209;breachof,7,26,28,30,57,71,74,77–79,87–88,98,

128,158,180,186,188,195,219;enhancement,142,188–89,245;ThreeMileIsland,145–46.SeealsoMarkIcontainment;MarkIIcontainment;MarkIIIcontainment

reactorcoreisolationcoolingsystems(RCIC),8,12,218,274;Unit2,17,18,24,26,62,73,265–66;Unit3,65,66,69,266;UnitedStates,217

reactorcoremeltdown.SeemeltdownReactorSafetyStudy(AEC),192,214Reagan,Ronald,191“reasonableassuranceofadequateprotection.”See“adequateprotection”redundantsystems.SeebackupsystemsRegulatoryInformationConference(RIC),204–6,217,219–20,260–61relocationofresidents.Seeevacuationofresidentsrem(unitofradiation),27,274residents’evacuation.Seeevacuationofresidentsrestartofreactors,46,151,224,225,227,228,229;Hamaoka,170–71;Kashiwazaki-Kariwa,228,239;

Monju,286n1;Nodapromises,172,223;NRArole,241;Ohi,224,229,230–31;ThreeMileIsland,142

retrofitting.SeebackfittingRIC.SeeRegulatoryInformationConference(RIC)Richter,C.F.,43Richterscale,281n1

riskanalysis,191–97,201,234,253,259.Seealsoprobabilisticriskassessment(PRA)RokkashoReprocessingPlant,240Roberts,Thomas,197RonaldReagan(ship).SeeU.S.S.RonaldReaganRoos,JohnV.,69,85,87,88–89,125,132,134,278

SafetyCommission.SeeNuclearSafetyCommission(NSC)safetyreportsandrankings.SeenuclearplantsafetyreportsandrankingsSakurai,Katsunobu,106–7salt,100,131,134,135,137,286n1saltwater.SeeseawaterSAMA.Seesevereaccidentmitigationalternatives(SAMA)SAMGs.Seesevereaccidentmanagementguidelines(SAMGs)sand,88,90,91,98sandbagging,37,175SandiaNationalLaboratories,134,264,265,286n3;CRAC2study,207–9,211,212,215,216,219,220;

SOARCAanalysis,217SanOnofreNuclearGeneratingStation,115,128SanrikuCoast,9–10,40,51,52,53Santiago,Patricia,220scale.Seeearthquakes:magnitudescales;instrumentscaleproblems;InternationalNuclearand

RadiologicalEventScale(INES)scandals,46,48,50scenarios.See“best-estimate”scenarios;worst-casescenariosSchaperow,Jason,220schoolsandschoolchildren,148,160,161,162Scidmore,ElizaRuhamah,282n4ScienceandTechnologyAgency.SeeJapanScienceandTechnologyAgencyScranton,William,III,148seawalls,10,53,231,246,250seawater:emergencyuse,10,33,57,60–62,65,67,72,77,79,86,97–100,107,121,123–24,131,137,

206,265;normaluseincooling,7,19,40–41,52secrecy,40,51,151,152,179,184,212,215,219–20,257;ofinspections,223.Seealsoclassified

informationSeismicIsolationBuilding,4,9,37,75,80–81,85–86seismology,2–5,41,42–44,51,63,114,229.SeealsofaultlinesSelf-DefenseForces(SDF),21,22,96,97,98–99,118,121,122,285n5SenateEnvironmentandPublicWorksCommittee,94,182Sendai,1,3,5September11,2001,terroristattacks(9/11),95,173,208–10,211,235,241severeaccidentmanagementguidelines(SAMGs),200,202,215,275,287n4severeaccidentmitigationalternatives(SAMA),259–60shareholders’meetings,165–66Sheron,Brian,64,134,217,278Shimizu,Masataka,21,25,50–51,67,73,76–77,107,277;resignation,165,166Shimokobe,Kazuhiko,227–28,277sievert(unitofradiation),27,275simulatedaccidents.Seecomputersimulationandmodeling;emergencydrillsSmith,AileenMioko,110,277SOARCA.See“StateoftheArtReactorConsequenceAnalyses”(SOARCA)

soilcontamination,120,160,162–63,178,214,254,256sourceterm,126–30,132,133,137–40,189–90,206,214,216,288n8;definition,275SouthKorea,68,160SovietUnion,39.SeealsoChernobylnuclearaccident,1986SPEEDI.SeeSystemforPredictionofEnvironmentalEmergencyDoseInformation(SPEEDI)Speis,Themis,197spentfuel,drycaskstorageof.Seedrycaskstoragespentfuelpools,7,70–71,76,81,83–84,88,100,121,123–24,131,132,139,158,159,163,174,256,

275,289–90n8;instrumentation,236;inPWRs,284n6;risks,210–11;Unit1,57,70,88,89,90,93,121–22,137;Unit2,70,88,89,90,93,121–22,137,267;Unit3,70,78,88,89,90,91,93,99,122,137;Unit4,69–71,81,82,87–93,95–96,121,123,133,136–37,255;UnitedStates,255

StateDepartment.SeeU.S.StateDepartmentstategovernments,64,147,148,283–84n5State-of-the-ArtReactorConsequenceAnalyses(SOARCA),130,204,205–6,211–21,268,275,285n3,

288nn9–10,289n1stationblackout.Seepoweroutagessteel:inreactorcontainment,5–6,14,48,113,188;inspentfuelstorage,7,70,83;vulnerabilityincasesof

meltdown,7,113,195,219storageofcontaminatedmaterials.SeedisposalandstorageofcontaminatedmaterialsStrauss,LewisL.,39“stresstests,”170–71,224–25,229,230–31,259strontium-90,127Stutzke,Martin,287n6Sugaoka,Kei,48Sullivan,Randy,216Sumatraearthquake,2004,47SurryPowerStation,213,214,215,216,218Svinicki,KristineL.,167–68,172–73,182,183,234,288Sweden,189,254SystemforPredictionofEnvironmentalEmergencyDoseInformation(SPEEDI),58–59,63,118,207,275

Takekuro,Ichiro,60,61,277taxation,40,178,204,226,230television,1,10,12,33,54,55,59,62,85,91,97,171,180;Edanoon,103;UnitedStates,115–17tellurium,109,118,156TEPCO.SeeTokyoElectricPowerCompany(TEPCO)terroristattacks(hypothetical),183–84,209,211,214,241terroristattacks,September11,2011.SeeSeptember11,2001,terroristattacks(9/11)Thornburgh,Richard,145,148ThreeMileIslandnuclearaccident,1979,14–15,44–45,101–2,140–54,188,202;cleanup,146,164;

industryeffectandresponse,58,61,112,168,205;INESrating,103–4;NRCeffectandresponse,152,187,188,195,196,200,232,253.SeealsoKemenyCommission

ThreeMileIslandNuclearGeneratingStation,143thyroidgland,27,99,127,129,133,134,138,139;potassiumiodideand,273tidalwaves.SeetsunamisTohokuEarthquake,2011,1,3–5,9,10,13,47,282n5Tokai,43Tokaimuraresearchcenter,40;nuclearaccident,1999,37–38,103Tokyo:earthquakevulnerability,229;protests,223,223;radiationthreatto,77,78,79,89,90,124,133,

134,138,139,140,256

TokyoElectricPowerCompany(TEPCO),48–54,61;blamed,244;blame-placingby,103,180,244;communications,76–77,107–8,264;compensationplan,165,289n4;cover-upsandfalsification,48–49;denialof“owning”radiation,179;disasterresponse,12–13,16–26,30,55,59,60–61,85,86,88,100;finances,165,178–79,226–28;Hatamuracommitteecriticism,226;incestuouspractices,47,48;mediacoverage,107;newmanagement,227–28,239;NRCrelations,125,135,136,155,163;opennesstohelp,100,102,131,134–35;postmortemarguments,246–47,266–67;poweroutagepreparation,203;pre-disasterretrofitting,202;pressconferences,67;protestsagainst,161;publicrelations,107–8,264;radiationreadings,97;recoveryplan,163–66;repoweringefforts,97,99;self-assessment,180;shareholders’meetings,165–66;sitingandconstruction,40,41,42;tsunamiplanning,51–54;watercontaminationproblem,158,159–60.SeealsoFukushimaDaichinuclearplant

tornadoes,188,192,249,253torus.Seewetwell(torus)Toshiba,164,290n10Trapp,Jim,77,78–79,80,84,85,86,136,278Trautman,Stephen,88,278travelers,American,93,99–100tsunami(word),282n4tsunamis,9–13,11,22–23,229,247–48;damagefrom,53,63,159,250;effectonfishingindustry,156;

evacuationafter,57–58;fatalities,98;IndianOcean,47;Minamisoma,Japan,106–7;planningfor,51–54,171,246;searchforvictims,181;TEPCOview,180;U.S.warnings,34

turbinebuildings,10,30,53,56,62,158,160,276turbinegenerators,5,8,48,56TurkeyPointNuclearGeneratingStation,249

Ulses,Anthony“Tony,”69,77,78–79,80,84,85,86,95,278uniforms,284–85n2.SeealsocompanyuniformsUnionofConcernedScientists,94,106,193,201,206,283n1,286n1;lawsuitby,194UnitedStates:aidfromsought,77;AtomsforPeace,39–40;earthquakehazards,113,114;generation

equipmentinJapan,282n8;westernstates,64,99,113,114,128,138,139.SeealsoAlaska;California;nuclearplants,U.S.;NuclearRegulatoryCommission(NRC);ThreeMileIslandnuclearaccident,1979;WhiteHouse

uranium,7,37,171;infuelpellets,5,271U.S.AirForce,97U.S.AtomicEnergyCommission.SeeAtomicEnergyCommission(AEC)U.S.citizens.SeeAmericansU.S.Congress,36,92,116,187,205,246,247;AtomicEnergyAct,187;EPAct,204–5;hearings,85,92,

93–94,182,183,185;ThreeMileIslandinvestigation,149,193U.S.DefenseThreatReductionAgency.SeeDefenseThreatReductionAgencyU.S.DepartmentofDefense,134,138U.S.DepartmentofEnergy(DOE),63–64,68,133,134,137,139;collaboration,102,131,288n5;Office

ofNavalReactors,68,88,89;RadiologicalAssistanceProgram,84,97;simulations,99.SeealsoNationalNuclearSecurityAdministration;SandiaNationalLaboratories

U.S.DepartmentofHomelandSecurity,99–100,114U.S.DepartmentofState,80,92–93,139U.S.Embassy,Tokyo,61,62,69,80,100,129,132;contingencyplanning,124;fearswithin,87,89,133;

NRCat,77,84,86,100,125U.S.EnvironmentalProtectionAgency(EPA),80,114,126,129,132,138,139,284n8U.S.FleetActivitiesYokosuka,78,79–80U.S.GeologicalSurvey,4,44,114,282n5U.S.military,68,69,77,78,88,97,121,138,160

U.S.Navy,68,88,160U.S.NuclearRegulatoryCommission.SeeNuclearRegulatoryCommission(NRC)U.S.S.R.SeeSovietUnionU.S.S.RonaldReagan,68

vaguelanguage:inguidelinesandstandards,48,187,190,191,194,224,290n2;fromsourcesonFukushimaevents,22,98,130

vanLoon,Eric,206,208ventilation,19–20,236,238,251,276;filters,128,188,231,254,255,268;governmentapproval,21–22,

30,31;NRAmeasures,241;planningfor,169,246;policyrecommendations,197–98;ThreeMileIsland,146,148;Unit1,19–20,22,24–26,28–32,57;Unit2,25,73–74;Unit3,65,66–67,69.Seealsoexhauststacks;hardenedvents

video,12,16,54,61,95;conferencing,25,86Virgilio,Martin,86,278;eventmonitoring(days2–4),61–62,63–64,77;eventmonitoring(days5–8),81,

85,87,89,98–99,102;eventmonitoring(days9–10),125,132–33,134,138;responsetoNTTFreport,233

Virginianuclearplants.SeeNorthAnnaPowerStation;SurryPowerStationVogtleElectricGeneratingPlant,245,282n6,288n1voluntaryindustrymeasures,154,170,173,198,199–200,202–3,235–36,253;Japan,51–52,157,246–

47.SeealsoFLEXprogram;severeaccidentmanagementguidelines(SAMGs)vonHippel,Frank,192

Wagner,Brian,36water,fresh.Seefreshwaterwater,ocean.Seeseawaterwatercannons,90,96,97,121,122watercontamination.SeeradioactivewaterWaxman,Henry,93weather,128,207–8,214,219,221,249.Seealsohurricanes;tornados;windWeber,Mike,138,278Weiss,Ellyn,194westernstates(U.S.).SeeUnitedStates:westernstatesWestinghouseElectric,39,200,290n10;AP1000reactor,114,244,245wetwell(torus),6,19,62,73,75,136,267–68,276,284n7;breaches,77–78,79,266;scrubbingin20,28,

267;ventilation,238WhiteHouse,92,111,129–30,137–39,140,205;NRCrelations,61,89,129,130,132,133,137–39,166,

177;OfficeofScienceandTechnologyPolicy,133,267;ThreeMileIslandinvolvement,147,148.SeealsoKemenyCommission

Wiggins,Jim,124,133,278Wilson,George,168wind,55,58,77–80,82,87,97,118,119,126,128,152,156,207;downwindfatalities,211;Hurricane

Andrew,249;Tokyoand,77,78,79,89,90,133,134WorldNuclearAssociation,35worst-casescenarios,125,126,129–30,132,133,138,187;inCRAC2,208,215,288n8;defense-in-depth

approachto,248;discussedinclosedNRCbriefing,216;ignoredinFLEXplan,238

xenon-133,146

Yokosukanavalbase.SeeU.S.FleetActivitiesYokosukaYokotaAirBase,97,98

YomiuriShimbun,46,47Yoshida,Masao,21,243,277;death,284n1;insubordinationby,60–61,86;Kanrelations,25,31;March

11management,10,20–21,23–24,25–26,30–31,32,33,37;March12–14management,37,55,57,60–61,65–68,73,74,75,76,80–81,85–86;post-disasterstatements,13,85

Yoshizawa,Atsufumi,243,277

zirconium,5,6,7,88,145;ignitionof,71,82,99,211

PUBLISHINGINTHEPUBLICINTEREST

ThankyouforreadingthisbookpublishedbyTheNewPress.TheNewPressisanonprofit,publicinterestpublisher.NewPressbooksandauthorsplayacrucialrole in sparking conversations about the key political and social issues of ourday.

We hope you enjoyed this book and that youwill stay in touchwith TheNewPress.Hereareafewwaystostayuptodatewithourbooks,events,andthe issues we cover: • Sign up at www.thenewpress.com/subscribe to receiveupdatesonNewPressauthorsand issuesand tobenotifiedabout localevents• LikeusonFacebook:www.facebook.com/newpressbooks

• FollowusonTwitter:www.twitter.com/thenewpress

PleaseconsiderbuyingNewPressbooksforyourself;forfriendsandfamily;ortodonatetoschools,libraries,communitycenters,prisonlibraries,andotherorganizationsinvolvedwiththeissuesourauthorswriteabout.

TheNewPress isa501(c)(3)nonprofitorganization.Youcanalsosupportourworkwithatax-deductiblegiftbyvisitingwww.thenewpress.com/donate.