STATE OF DELAWARE

UNIVERSITY OF DELAWARE

DELAWARE GEOLOGICAL SURVEY

OP~N FILE REPORT No. 15

GEOLOGIC ASPECTS OF DISPOSAL OFHIGHLY RADIOACTIVE NUCLEAR WASTE

BY

NENAD SPOLJARIC

NEWARK, DELAWARE

MAY 1981

GEOLOGIC ASPECTS OF DISPOSAL OFHIGHLY RADIOACTIVE NUCLEAR WASTE

Nenad Spoljaric

INTRODUCTION

This report was prepared to provide a simple but com­prehensive overview of programs and concepts of highlyradioactive waste disposal. This report is not based onoriginal research, but was prepared from data and informa­tion reported in voluminous publications of the U. S. Depart­ment of Energy, the Nuclear Regulatory Commission, the U. S.Environmental Protection Agency, and the U. S. GeologicalSurvey.

The importance of nuclear waste disposal for futuredevelopment of nuclear energy in the United States wasformally recognized in 1976 when the National Waste TerminalStorage Program was established. The Program is directedby the Office of Nuclear Waste Management (ONWM) in the U. S.Department of Energy.

The Department of Energy is directed by law (the AtomicEnergy Act of 1954, The Energy Reorganization Act of 1974,and the Department of Energy Organization Act of 1977) todevelop technology for safe disposal and management ofhighly radioactive wastes.

On February 12, 1980, President Carter called for aNational Plan for Radioactive Waste Management stronglyemphasizing the development of technology for safe disposalof nuclear waste in mined geologic repositories.

The chronology of the united States' developments inthe disposal of radioactive wastes is shown in Table 1.

At present there are four major projects in progress: Theprogram at the Office of Nuclear Waste Isolation in Columbus,Ohio; the Basalt Waste Isolation Program in Hanford, Washington;the Nevada Nuclear Waste Storage Investigation at the NevadaTest Site; and Seabed Project. All these projects involve

1

TABLE 1.

1957

1963­1967

1968

1970

1972

1974

1976

1977

1978

1979

DEVELOPMENTS RELATED TO NUCLEAR WASTE DISPOSAL PROGRAM.*

National Academy of Sciences/National Research Council recommendation fordisposal of nuclear waste in salt deposits.

Project Salt Vault-A demonstration of emplacement of encapsulatednuclear materials in a salt mine in Kansas.

Evaluation of basalts in Hanford, Washington begins.

Work on the proposed pilot facility at Lyons, Kansas begins.

Termination of work at Lyons. Search for pilot facility site continues in Kansasand expands to New Mexico. U.S. Geological Survey studies Gulf Coast regionsalt domes. USGS begins studies in Paradox basin in Utah.

Waste Isolation Pilot Plant (WIPP) facility proposed for New Mexico. Evaluationof salt domes as a host geology begins.

National Waste Terminal Storage (NWTS) Program established. Broad programof geologic exploration proposed in 36 states. Evaluation of geologic formationsat Nevada Test Site (NTS) begins. Evaluation begins of Permian basin in Texas.

Evaluation begins of Salina salt basin in Michigan, Ohio, and New York.Evaluation begins of Palo Duro sub-basin in Texas.

Study areas recommended in Gulf Interior and Salina regions. President Carterestablishes the Interagency Review Group on Nuclear Waste Management(IRG). Office of Nuclear Waste Isolation (ONWI) formed. IRG issues report indraft form; solicits comments; conducts public meetings; holds sessions withrepresentatives of various interest groups.

IRG issues report in March. Investigations of nonsalt geologies accelerated onIRG recommendation. Work proceeds at three salt basins (Gulf Coast. Paradox,and Permian), as well as at Hanford. NTS, and WIPP. Efforts begin to organizeState Planning Council to aid in information exchange between federal andstate officials. Department of Energy issues draft Generic Environmental ImpactStatement (GElS) proposing that emphasis should be on mined repositories asdisposal technology.

*Source: ONWI-19, 1979.

2

many different fields of science. It is important that thedata generated in these studies are readily available to allthe scientists involved in the nuclear waste disposal pro­gram. The management scheme shown in Figure 1 was designedto allow for this internal flow of information.

In addition, contacts are maintained with the Associationof American State Geologists and with several foreigncountries having similar programs underway. Particularlyclose consultations are carried out with the Federal Republicof Germany, Canada, and Sweden.

The Delaware Geological Survey does not anticipatedisposal of highly radioactive waste in Delaware. Neverthe­less, this report was prepared because Delaware citizenshave expressed general concern about nuclear power issuesand we seek to clarify one geologic aspect of these issues.

BACKGROUND

The realization that our present energy sources, suchas oil and natural gas, are finite, has led to an increasingemphasis on nuclear energy, i.e. nuclear power plants. Theelectric energy produced by such power plants may becomemore important in the future not only in the united States,but also throughout the world.

Thereactor.necessaryitself is

basic component ofTo understand theto understand thebased.

a nuclear power plant is aoperation of a reactor it isprocess upon which the reactor

All matter is made up of atoms that consist of nuclei(containing almost all the mass) surrounded by orbitingnegatively charged electrons. The nucleus is composed ofone or more protons (positively charged particles) and oneor more neutrons (no charge). The particular element isdetermined on the basis of the number of protons. Thenumber of electrons is equal to the number of protons andthus the total charge of an atom is neutral. The number ofprotons is also called the atomic number.

Each element can have various numbers of neutronswhich gives rise to isotopes of the same element with dif­ferent total mass. All the isotopes of all the elementsare often referred to as nuclides.

3

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Many nuclides are unstable and change into othernuclides. Such a change is accompanied by emission ofradiation. The time it takes for one-half the mass ofa nuclide to change (decay) into another is called itshalf-life. The radioactive elements found in nature,such as uranium and thorium, have very long half-lives:over one billion years.

A nuclear power plant utilizes heat produced in thereactor to convert water into steam which runs turbineswhich, in turn, produce electricity. The heat is producedby the fission process (splitting of the nucleus into twoor more parts) which takes place when a neutron is absorbedby heavy elements such as uranium (Fig. 2). This processtakes place within the nuclear fuel (Fig. 3) (naturaluranium). The heat generated is removed by heavy water(water in which the hydrogen atoms consist of deuterium,the stable isotope of hydrogen of mass 2) that flows overthe nuclear fuel. The hot heavy water passes throughheat exchangers (boilers) thus transferring the heat toordinary water to produce steam.

During the fission process new nuclides form, many ofwhich are unstable. For example, one of the products isplutonium. Plutonium, on absorbing a neutron also givesoff heat, other fission products, and more neutrons.

As the fission process progresses the number of neu­trons of the fission products becomes so large that theirpresence in the reactor core begins to cause a reductionin the nuclear reaction. When this happens the fuel (Fig.3) is removed from the reactor and the unused fissionmaterial, plutonium in particular, is recovered.

Problems

Recovered unused fission material has to be disposedof in a safe manner. Because it is highly radioactive, itcannot, and should not, be disposed of in a conventionalmanner, such as in landfills.

The future utilization of nuclear energy in the unitedStates depends to a great extent on the development oftechnology for the safe disposal of nuclear waste (Fig. 4).

Highly radioactive waste can be either water containinghighly radioactive materials in solution, or spent or repro­cessed nuclear fuel from reactors. Power plants generate

5

BEGINNING OF LIFE FISSION TRANSITION END OF LIFE

446.2 kg 23BU • 435.2 kg 238U

'\: 2J9pu 239pu0.75 kg 10.2 kg • 2.8 kg

5.3 kg 1.0 kg 240Pu

0.5 kg 241 pu

0.8 kg TRU

15.2 kg 235U

2.3 kg 236U ••

•

2.2 kg 236U

3.7 kg 235U

Figure 2. Isotopic changes in nuclear fuel during burnup(Source: ONWI-39).

6

••••••THE ZIRCALOY TUBES AREASSEMBLED IN BUNDLESTO fORM A fUEL ROO

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PRESSED PELLET SINTERED PELLET GROU.ND PELLET•

SINTERED AND GROUNDURANIUM OXIDE PELLETSARE LOADED AND SEALEDIN THIN ZIRCALOY TUBES ••••••••

ZIRCALOY TUBE

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URANIUM OXIDEPOWDER

END CAP

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Figure 3. Steps leading to assembled nuclear fuel rod(Source: ONWI - 39) .

7

DEPLETEDURANIUM

A

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ISOTOPICENRICHMENT

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REPROCESSING

jINTERMEDIATELEVEL WASTE

HIGH LEVEL WASTE

tllLIJGEOLOGICDISPOSAL

Schematic diagram of once-through (spent fuel) (A),and reprocessed (high level waste) (B) cycles(Source: ONWI-39, 1979).

8

other waste as well, and although they are produced in largequantities, they are not as radioactive as spent fuel.

Radioactive wastes that contain more than a specifiedamount of radionuclides heavier than uranium are calledtransuranic. They are of particular concern because theyhave long half-lives and emit alpha rays.

There are about 70 operating commercial nuclear powerreactors in the united States (U. S. Department of Energy,1980). This represents about 50,000,000 kilowatts of elec­trical generating capacity. The amounts of projectedgrowth of generated energy and spent fuel up to and includingthe year 2020 are shown in Table 2, and the amount of radio­activity and heat generated by spent nuclear fuel are shownin Figure 5.

Clearly, the disposal of highly radioactive waste mustbe carried out in a way so that no health hazard exists.It must be stressed that no generally accepted technologyfor the management and disposal of such waste has yet beendeveloped although extensive research is underway.

Present Methods of Disposal

Most of the spent fuel and high level waste is kept intemporary storage facilities located either in the vicinityof or away from the nuclear power plants.

Water-Pool Storage

The method of temporary storage of spent and repro­cessed fuel in water-filled basins is used world-wide. Thefuel is either placed in special baskets (unpackaged) or intostainless steel canisters (packaged) before storage in waterpools. Waste is cooled by circulating water (Aikin, Harri­sone, and Hare, 1977).

Canyon-type Storage

Nuclear waste is stored in rocks in large cells andshielding is provided by thick concrete walls. Nuclearwaste is cooled by either natural or forced convection ofair or a non-reactive gas. The gas is either cooled andrecirculated or filtered and discharged into the environment(Anderson and Meyer, 1980; Fig. 6).

9

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Caisson-type Storage

Nuclear waste is stored in shallow holes in the ground.Shielding is provided by the ground and concrete plugs.Cooling is maintained by natural conduction of heat throughthe ground (Anderson and Meyer, 1980; Fig. 7).

Cask-type Storage

Nuclear waste is stored in concrete cylinders on theearth's surface with shielding provided by the thick concretewalls. Cooling is accomplished by conduction through thewalls (Anderson and Meyer, 1980; Fig. 8).

Types of Reactor-Generated Wastes

Solid, liquid, and gaseous wastes are generated bynuclear reactors.

In addition to spent fuel, the solid waste includespieces of equipment, valves, and pipes, which have all be­come radioactive. A considerable amount of the solid wastecan be compacted and thus reduced in size for easier disposal.

The liquid waste comes from a variety of sources suchas decontamination facilities and floor drains. The radio­activity of this waste is reduced by di~ution (Aikin,Harrison, and Hare, 1977).

The gaseous waste is made up of several radioactivegases such as: krypton, xenon, and tritium. The radioactivecomponents of waste gases are reduced to safe levels byfilters, such as charcoal (Aikin, Harrison, and Hare, 1977).

PRINCIPAL CONCEPT OF DISPOSAL

Mined Geologic Repository

Requirements

The repository must be deep enough to be protected fromany possible disturbances or disruptions at the surface suchas erosion, climate, and weathering. The actual depth is

13

GASKET

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ELLIPSOIDALEND CAP

FUEL ASSEMBLYBOTTOM NOZZLESUPPORT CRUCIFORM

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Figure 7. Caisson-type storage facility (Source: NUREG/CR-1223, 1980).

14

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Figure 8. Cask-type storage facility (Source: NUREG/CR-1223, 1980).

15

dependent on many variables and would be determined indi­vidually for every specific site.

The host rock mass must be large enough to assure geolo­gic isolation and adequately disperse or contain all of theperturbations and loads induced by the repository itself(U. S. Department of Energy, 1980).

Other factors that will also have to be carefullyconsidered are the inclination of rock layers, rock frac­tures, and faults. The repository site should be geologi­cally calm, that is, there should have been no earthquakesor volcanic eruptions over at least the past 100 millionyears.

In addition to geology, hydrologic factors would playan important role in selecting a prospective repository site.Ground water is present in varying degrees in nearly allrocks. The disposal of nuclear waste requires that the hostrock allow for only a minimum amount of water percolation,thus preventing water contaminated with radioactive materialsfrom reaching areas where it may pose health hazards.

Surface water such as lakes or rivers must not be presentin the repository area to avoid flooding or entrance of waterinto the repository.

Host Rocks

Shales

Shale is a rock formed by compaction and consolidationof mud. Mud is a sediment composed predominantly of claysand silts. Shales are laminated and can break easily alongthe planes of lamination, are not strong, contain largeamounts of moisture (water), but have low primary permeability.

Clay minerals composing shales have a capacity to ex­change elements in their structure (ion exchange property)with those from the surrounding environment. Chemicalchanges and temperature may significantly affect the strengthand VOlume of shales (ONWM and USGS, 1980). Sometimes shalescontain fractures that may be filled with other mineralssuch as calcite.

Shales are widespread in the United States and occupylarge areas, particularly in the central part of the country.

16

Salt Deposits

Salt rocks showing promise as host rocks for disposalof high level nuclear waste are found in two forms: saltdomes and bedded salt (ONWM and USGS, 1980) often inter­bedded with other sedimentary rocks such as shale or lime­stones. Salt rocks are known to flow slowly through theground either laterally or upward, breaking through over­lying rocks and forming domes or diapirs.

Although heat may reduce the strength of salt rocks,high thermal conductivity of salt is conducive to heatdissipation, which is important from the standpoint ofnuclear waste disposal. Water percolation or permeabilityin undisturbed salt beds is essentially nonexistent. Theability of salt to flow (creep) is an advantageous charac­teristic because it tends to seal discontinuities (ONWM andUSGS, 1980). The prospective salt deposits are locatedmainly in 'the Great Lakes area and central and southernparts of the United States.

Basaltic Rocks

Basalts are dark colored volcanic rocks of large arealextent which solidified from cooling lava at the earth'ssurface. In the United States they are mainly concentratedin the Great Lakes area and northwestern part of the country.

Basalts are usually very dense and very strong, havelow primary porosity and permeability, and contain verylittle moisture. sometimes basalts may have well developedjoints (secondary porosity and permeability) that mayormay not be filled with other minerals, decomposed basalt,or water.

Basalts are generally unaffected by temperature changes(ONWM and USGS, 1980).

Granitic rocks

Granite is a hard, crystalline, intrusive, igneousrock, usually light colored and found as large bodies formedbeneath the earth's surface by consolidation of coolingmolten magma.

The primary porosity and permeability of granite arevery low. Granite is strong, rigid, and does not deform

17

easily, although it may crack due to the expansion or con­traction of some minerals (ONWM and USGS, 1980).

Granites are not bedded but often contain joints(planes and partings) that may be partially open (secondaryporosity and permeability). Large granite bodies are foundin many parts of the United States.

Selection of the Site

The selection of a repository site will be a long anddetailed process. The Nuclear Regulatory Commission isdeveloping licensing criteria while the Department of Energy(Gray, et al., 1976) is preparing performance criteria. Thesite selectron process described below is hypotehticalalthough it closely follows the criteria considered by DOEand NRC.

The steps that would be followed in complying with thesecriteria when adopted, should be, and would be, based onthe necessity to minimize the risk of releasing radioactivityinto the environment. The actual selection of a repositorysite would be done in three general stages (DOE Final EIS,Vol. 2,1980).

In Stage I a broad regional site selection processwould be initiated. This would be followed by a more de­tailed investigation of promising smaller areas in Stage II.The specific sites would be studied in detail in Stage IIIleading to the final selection of the most suitable site.

A general outline of the criteria considered in each ofthe three stages is shown in Figure 9. Details of investi­gations of specific sites may vary depending upon particularconditions and characteristics of the area and the entireprocedure is subject to review.

Disposal of Waste

The following discussion deals with disposal in salts,granites, shales, and basalts. It should be stressed thatalthough there may be specific and particular requirementsapplicable to different rocks, the fundamental principles ofwaste disposal are applicable to all disposal sites.

One of the most important factors to be consi-ered is theheat generated by wastes and its dissipation through the hostrock (DOE Final EIS, Vol. 1, 1980). Dissipation depends on

18

C(lolTlNENTALU.S.

tTECTONIC CONSIDERATI(lolS

HYDROLOGIC CONSIDERATIONS

STAGE I DATA BASE:

AVAI LABLE LITERATURE. REMOTE SENSING_ IMAGERY, EXISTING GEOLOGIC

EXPLORATI (lol DATA

SELECTED CANDIDATE REGIONS - TYPICALAREA.500,lOOkm2- - - -t- - -- -- -- -- ------ -- ----

GENE

"RALGEOLOG IC STAGE II DATABASE:~ STAGE I DATA PWSEXTENSIVE GEOLOGIC_ MAPPING, GENERIC ROCK PROPERTIES

CONSIDERATIONS RESEARCH, LOCAL HYDROLOGY, CLIMATIC~O0 DATA, GEODETIC MEASUREMENTS,~ MICROSEISMICITYNETWORKS

~ELEmDC~IDMEAREAS~TYPICALAREA.IO,lOOkm2 __

SITE SPECIFI GEOLOGICCONSIDERATIONS•o

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STAGE II DATA PWS SITE EXPLORATI(lol DATA,DRILLING, GEOPHYSICS, IN-SITU TESTINGOf STRESS, HYDROLOGY, ROCK PROPERTIES

OPTIMUM REPOSITORY SITE _ TYPICAL AREA. 20 km2

Figure 9. Three major stages leading to the selectionof a repository site (Source: DOE/EIS-0046F),

19

the spacing of individual canisters containing waste and thecharacteristics of the host rock. For example, 2 - 6 timesmore waste can be stored in equal volume of granite orbasalt than salt (DOE Final EIS, Vol. 1, 1980).

Theoretically, a geologic repository would be locatedat the depth of betwp.en 600 m and 1,000 m and would occupy anarea of about 800 hectars (2,000 acres). During the firstfive years of operation the interaction of waste with therepository rocks would be investigated, a variety of scientificobservations made, and other studies conducted. Results ofthese studies may demonstrate the need for modification ofthe existing repository design and improvements in the designand operation of future repositories.

The concept of a geologic repository is shown in Figure10. Projections and estimates of the maximum amount ofwaste and maximum number of canisters in repositories ofdifferent rock types are shown in Table 3.

STORAGE AREA FORMINEO MATERIAL

elEVATOR SHAFT FORSPENT FUel OR FUELREPROCESSING WASTES

WASHINGTONMONUMENT

EMPIRE SlATEBUILDING

I .!

'",I,

Figure 10. Probable design of underground mined geologicrepository (Source: DOEjEIS-0046F)

20

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fuel.

Very Deep Hole Disposal

Nuclear waste would be placed in holes as much as10,000 m (32,800 feet) deep, in rocks of great strength andlow permeability (DOE Final ElS, Vol. 1, 1980). The actualdepth would have to be decided for every specific site andwould have to provide effective isolation of the waste fromthe biosphere.

Among other geologic factors that would be consideredare: rock composition, resistance to earthquakes and otherdistructive geologic processes, ground and surface waters,stresses in the rocks, and the effect of heating by waste onthe host rock (DOE Final ElS, Vol. 1, 1980).

The main problems with this concept are lack of tech­nology to conduct very deep drilling, inability to retrievewaste, and difficulties in keeping the hole open while thewaste and sealing plug are being emplaced (DOE Final ElS,Col. 1, 1980).

Because of the high cost only unprocessed spent fuelrods and high level waste would be disposed of; transuranicwastes would be most likely placed in mined geologic reposi­tories (DOE Final ElS, Vol. 1, 1980).

Very deep hole system would be designed for disposal of10,200 canisters per year of spent fuel or 2,380 canistersof high level waste (DOE Final ElS, Vol. 1, 1980).

with a 40-year repository operation period, emplacementof spent fuel would require 68 holes per year with 150canisters placed in each. High level waste would requireemplacement of 375 canisters per hole in six to seven holesper year (Bechtel, 1979a). The basic outlines of the disposaland management system are shown in Figure 11.

After all waste canisters are emplaced, the hole wouldbe sealed to isolate the waste from the biosphere by pluggingit with cement or crushed rocks or both.

Rock Melting Concept

This concept calls for placement of radioactive wasteinto rock cavities. The heat generated by the waste wouldmelt the surrounding rocks, eventually incorporating thewaste. It is anticipated that in about 1,000 years the meltwould solidify, trapping the radioactive waste (DOE Final EIS,

22

FUEL CYCLE DIAGRAM - VERY DEEP HOLE DISPOSAL

Fuel,.....--oolR...-... I---...,Facility

VeryD-.pHah

DrYling-..Emplauw..."t_......100E_

....wl

NotII: U bltween bo:ua~ trenspotUtion

betwMn f-=ilities

M;nod

G~ogic

RlIPQSitory

r- -,I EI.... II HLW II ... i-----oiI Spent II Fuel IL__ ...I

Hulls andOth... TRU-

SplInt F....-IyPec:bving

Facility

r--- --'"To I

Elth. IRo"-"'.

0' ISpent Fuel IPackaging I

L.__ __J

R_....Spen.

,....Fuel

II

R_Fue'

,SpentFuel AslMnbl_ I

II

ReKtorSpent ,....Fue'

HLW from F.... Reprae.ting '.cUllY

0'Spent Fuel A.-mblin

........ F_c.ninIn forR....k.'1lI

'_bUll Wat. fromPIHIinT........-v

f--LOMIlnSpecUI

i-- $1or.. 6ft VDH Site H IRI)IIlCt" D-.n,.,......~I-Pie Fecility in Shipping Cask endYOH Canis., Ship to YOH Site

c.ntrelnMeiWngFacility

LOild into On- Transfer to Em......

"- site C8ni1ter I-r- men! Facility at --!Em_eon_ ~~ ...v.. Monitor w..- ,IT_", Very D_p Hole

in Vary D.,. Hot- o.p HoIti c.nil_~

DrilIV-VDMp II...... PlY..8rt-.1Hole and s.t upE~tF"lity

_ofeon_PROCESS FLOW DIAGRAM - VDH DISPOSAL

Figure 11. very deep hole disposal concept; outline of disposalmanagement system (Source: DOE/EIS-0046F, 1980).

23

Vol. 1, 1980). Once hardened, the homogeneous mixture ofwaste and rock would be very resistant to leaching thusproviding even better long-term containment than mined geo­logic repositories (Bechtel, 1979a).

This disposal procedure would require high level waste,dissolved in water, to be injected into a cavity. The heatgenerated by the waste would drive off steam which would bepumped to the surface (Fig. 12). At the surface the steamwould be condensed and recirculated to cool the waste in thecavity during the waste emplacement phase. This would be aclosed system and no radiation would be released into theenvironment (Bechtel, 1979a).

After about 25 years the cavity would be filled and thewaste would be allowed to dry. The inlet hole would besealed. The waste temperature would then begin to rise androck melting would commence. It has been cal~ulated that itwould take about 65 years before the melt would begin tosolidify. During the melting phase the heat would preventground water from entering the waste area (DOE, 1979). Whenthe rock-waste melt solidified, the radioactivity of themass would be less than that of the uranium ore from whichnuclear fuel was originally extracted (DOE Final EIS, Vol. 1,1980).

The technological issues that would have to be solvedbefore initiation of rock-melting concept (DOE Final EIS,Vol. 1, 1980) are:

a) The necessary geologic information cannot bepredicted with available knowledge.

b) Data on rock-waste interaction are lacking.

c) No engineering or technical design of thefacilities has been attempted.

Island Disposal

The fundamental ideas and procedures of island disposalare shown in Figures 13 and 14.

The waste disposal would be similar to the mined geo­logic repository discussed elsewhere in this report. Atthis time the U. S. Department of Energy has no program toactively investigate this concept (Deutch, 1978).

24

.....-­Fool

_e1.F.iiiti. No..: Li.,. betwwn boxes

dllno1e w." tnutiporUition_tween fllCilitiei

Rock Melli", Repository

FUEL CYCLE DIAGRAM - ROCK MELTING

Spen.....­

F...,

Spen.-,F...,

I"'"......F-...-..., Uq."I--+..,...:.F:;"'::,'-I""_ I-"H",LW"-'-1

Alumbli. FRUity &L.._,...._.J RH-TRU

Hull. and 0......TRU wast.

MinedGeolOfic

Rllpoaitewy

• Drilling! ExcaViltfon

• W••e Empl-=emlln'

• Seating

• Rock Melting

IS. Expanlion Belowl

SpentFuel

a_GooITo Atmoapherel

tWo.. Gas Trutmllnt

Noncon.....N...... - Goo

(Filtration.

fueIR"''''ng Cool'" CooIod s.n.......PIon.

To_ eon_ ond

ISoIidfiutiont

WIlt.,

Liquid Waste Ji ....m

Chity

FLOW DIAGRAM - ROCK MELTING DISPOSAL

outline(Source:

Figure 12. Rock melting disposal concept;of disposal management systemDOE!EIS-0046F, 1980).

25

I+ ..........

'8'

Figure 13. Design concept of island disposal repository(Source: DOEjEIS-0046F, 1980).

The island concept is attractive because it could pro­vide an international repository if the needed arrangementsand agreements could be reached (DOE Final EIS, Vol. 1, 1980).

There are three different classes of islands which couldbe used as waste disposal repositories (DOE Final EIS, V01.1,1980) :

a) Continental islands, situated on continental shelves.

b) Ocean islands.

c) Islands in inland areas or in se"ismica11y activeisland arc areas.

The handling, disposal, and retrieval of waste canisters,and sealing of full repositories would be done fundamentallyin the same way as described for mined geologic repositories.The main advantage of island disposal would be that of anadditional barrier of fresh and ocean water (Fig. 13), andisolation and distance from inhabited (populated) areas.

26

FUEL CYCLE DIAGRAM _ ISLAND DISPOSAL

Note: L ~bo..denoIII b*-= latloil~"'lhMFuel

'E"-='I HLW II, TAU' • T_I W ) I----....~. MiningI or t • Em~m.rt

I - I • SooII",L Fuel J (See ex....ion

I II-----J- 8"owl. :§: -

....11 8ftCI other,..--_-1...'...._..'n....·~;;T;;AU;;:::_::.;...;;;;Feelltty

1"'"- -,T.Eh.... I

......" ••"" I.. I

_Fuel I--IL_-r_.J

--- -Fuel

I-- Fuel !_.IFuel MHmblletI_.,..... i-

F..,

HLW from f .... ReproceIII,. Fadlity..Spent F.... "-mbI_

........ F.ilild c.n....hI .... _lnt l

~

*hckage __ f~m LMd Into Shipping Inspect, Monitor Loo.CooksPIE FKltity in lsi..... e-k and Tr..-port MId o.contlitnfnate

_T_-01_"-'- to Em_btfon Port CII:kI end c.n... Ship

~ TrIIMPOf1to tMplCtCUklTn...... to EmpilCe c.nisten

'- eeblrklltlon and tud onto Deblirkation Port_...... -.... ........- RoomsinR Jal"DiY

ConIIruct Mned_Cooks_

0001.... _ L- to the PIE FeciHty

....-'- ~kflll Mined -- ---- _Condh....

~FIow~m-·IIIMd.......

Figure 14. Island disposal; outline of disposal managementsystem (Source: DOE!EIS-0046F, 1980).

27

Disposal in Ocean Sediments (Subseabed)

Nuclear waste would be emplaced in ocean sediments inareas that have been stable for millions of years. The actualemplacement would be accomplished by placing the waste in"penetrometers" (Bechtel, 1979): needle-shaped projectilesthat, when dropped from a height, penetrate the bottom sediments.

The penetrometer would have a nose cone to aid in pene­tration and tail fins for guidance. They would be designedto penetrate about 30 m (90 feet) into the bottom sediments.It has been shown that the holes made as the penetrometersentered the sediments would close spontaneously. Means wouldbe provided to track each canister to ensure proper penetra­tion and spacing (DOE Final EIS, Vol. 1, 1980).

The canisters would be designed so that waste contain­ment would be maintained for several hundred years (DOE FinalEIS, Vol. 1, 1980).

It is anticipated that any possible escape of radio­active components from the canisters would be a slow processso that leaked waste would be effectively diluted and dis­persed. In addition, the great depth of the water columnwould constitute a barrier to human intrusion. The evidenceat hand suggests that ocean-bottom clays could provide long­term containment of the nuclides (except for the elementsiodine and technetium) through their sorbtion, ion-exchanqeproperties, and very low permeabilities (DOE Final EIS, Vol. 1,1980). The outline of the procedure is shown in Figure 15.This disposal method would be applicable mainly to spentfuel and high level waste.

There are many problems related to this disposal methodthat have not yet been resolved. It appears that the totalarea re~uired for the disposal would be about 520 km 2 /year(215 mi /year) for high level waste and 930 km 2 /year(354 mi 2 /year) for spent fuel waste with the spacing of 300 m(984 ft) between canisters and the total waste of about5,000 metric tons/year (DOE Final EIS, Vol. 1, 1980).

Ice Sheet Disposal

Continental ice sheets could provide isolation of nuclearwaste. There are three possible ways of disposal in ice:a) canisters emplaced in shallow holes; b) an anchored cableattached to canisters for possible retrieval of waste, andc) storage facilities located on the surface with eventual slow

28

FUEL CYCLE DIAGRAM - SUBSEABED DISPOSAL

TrenlPOl1.mp....Monitor

(See Expansion Below)

No..: LiJl8$ botwNn boxesdenote waste transportlltionbetween facdities

SF

r·....lI HLW IIs':'. .1----..I F_' IL_ ..J

RH-TRU and om.~----.TRU wastes Mined

G~logM:

Repository

Ss-nt FlMI_mbly..........Facility

-------Al~ti~----_,

,-l.....L...l., IFuel HLW

r--_~R_I_.....:.;::::."....Fecility and HuUs

r- -,I To'_ ,

I _+_:.F::_::,'...~ Reproceaing I,. or I

I Spen.F_, II ..........L_ _J

R.....'SPlfttF_'

Re.etor......F_'

R.....'S..ntFuel

HLW From FUIII ReprocllDing FKility

'"Spent Fuel Assembliel

--""""BlICk to tM PIEFacilitY for Reuse

Pack... W...... From PIEFlKility in Sutts-bed 1-......-1

Disposal Canister

LNd I"to.Shipping Calk and

Transport toE......' ...tion Port

I~Monitor. R...... c.n..1--..--1 and o.contamiMte 1-......-1 From Shipping c.k

c.k and Can..... and PI.ce in T....ponrySto....... Neeeaary

Pi.... c.nister inOverpllCk SuiUble

for oee.n Transport~d Disposal

Ludo..PKked1-__-1 Canl,.. A.......

TIUIPOf1 Ship

Close EmplKementHole if Not Closed

SuWciantly ThroughNatur.l Processes

Monitor WastePIIck. ConditionVia Monitor Ship

Transport $hlp

ReturftllO Portfor Next LNding

PROCESS FLOW DIAGRAMS - SUBSEABED DISPOSAL

Figure 15. Subseabed disposal; outline of disposalmanagement system (Source:DOE/EIS-0046F, 1980).

29

melting into the ice sheet (Battelle, 1974; EPA, 1979;ERDA,1976) (Fig. 16). The main advantages of ice sheetdisposal are remoteness from populated areas, cooling, andice barriers.

The outline of the procedure is shown in Figure 17.The disposal would probably be carried out either in theAntarctica or the Greenland ice sheets.

In the canister-meltdown concept the rate of descentthrough ice would be on the order of 1 to 1.5 m/day (FinalEIS, Vol. 1, 1980). Assuming an ice sheet 3,000 m (9,900 ft)thick, meltdown to the bedrock would take 5 to 10 years.The canister would be designed so that it would maintain avertical path from ice surface to bedrock.

The anchor emplacement concept is similar to the melt­down concept except that cables 200 m to 500 m long (660feet to 1,650 feet) would be attached to the canisters beforelowering them into the ice sheet. Instrument leads couldbe attached to the canisters for monitoring their conditionafter emplacement.

The surface storage facility concept would requirelarge storage units constructed above the snow surface(EPA, 1979). The set-up is shown in Figure 16. The canis­ters would be placed in cubicles inside the facility and aircooled. During the water emplacement phase the canisterswould be retrievable. The facility would be maintained abovethe ice for a maximum of 400 years after construction. Whenthe limit of the jack-Up pilings was reached the entirefacility would act as a heat source and begin to melt downthrough the ice sheet (Battelle, 1974).

Among the factors that are not well understood toeffectively employ ice-sheet disposal concepts are: icedynamics, climatic variations, possible effect of the wasteon the delicate glacial environment, and motion of contin­ental ice sheets and its effect on the waste canisters(Philbert, 1958; Zeller et al., 1973; Philbert, 1975).

Well Injection

Well injection technology is well developed, is widelyused by the oil industry, and has also been utilized recentlyin disposal of various wastes.

30

_noPI.,'

a

DrillingRio

Shieldlid CellPort F-eility

.........b Empl.clment

.,.. fDrill'":=£~~-;p I Rio

'~DriUecl I

CanilW' Hole

1.. -

.I,1

.....-C FtlCiIity_....--~

Figure 16. Schematic presentation of ice sheetdisposal concept; a) melt down,b) anchored emplacement, and c)surface storage (Source: DOE/EIS­0046F, 1980).

31

FUEL CYCLE DIAGRAM -ICE SHEET DISPOSAL

Fuel,....-----1 R~rocessing 1----...,Facility

ICE SHEET DISPOSAL

Note: Lines between boxesdenote waste tranapol'tationbetween facilities

MinedGeologic

Repository

r- -,• Either •• HlW I e PMltdown (Free Flow)

: or I-_...~ ConceptSpent I • AnchoNd Emplacement

I Fuel ConceptIL.. I e Surface Stol1lge Facility

--' Concept(See Expansion Bolow)

Hull. andOther TRUWad8.

SPent Fu.1AssemblyPackeging

FacilitY

r- --,I To Eith&r I

Reactor Fuel I RePl'oceaing ISPint 1--1--~!!"'-t ., IFuel Auemblies I Spent Fuel I

I Packaging IL .J

RuctorSpentFuel

HLWfrom Fuel Reproceaing Facility..Spent Fuel AISIImbli.

r-----------------I Retum Failed CanistenfOf' Repacking

Packa. w.te fromPIE Facility in

Ice S..... Disposal Canis....

Load in Special ShippingCask IWId Tl1Insport

to Embarkation Port

PIKe Caniste,.in e Shi.lded CellFacility tOf' leak

Checking andDecontamination

TraM'" CIInittersto Specially Deligned

Calks and LoadAboerd Trenaport Ship

e "'.ill HoI_0<

e Con....uct Surface Stor•• Facility

Tnnsport to De.,ltationPort lOuring Summer Mont_I

Intpect Casks andload onto Over-IceTransport V_hides

E~Canis'"

e In10 m.d ttot_for tdown concept0Jt for anchored concept

• Into Cubicl. for 1heSurlKe Storage Facilityeon....

Recycle CasksBack to.M

Em.rke.ion Port

PROCESS FLOW DIAGRAM - ICE SHEET DISPOSAL

Figure 17. Ice Sheet Concept; outline of management system(Source: DOE/EIS-0046F, 1980).

32

Well injection using grout was developed at the OakRidge National Laboratory for the injection into shales ofremotely handled transuranic liquid radioactive waste(ERDA, 1977).

Because of the availability of detailed data andsuccessful application of this technique in similar disposalfields, well injection is thought by some to be an economicalalternative in radioactive waste disposal.

The schematic outline of the procedure is shown inFigure 18.

Injection Concept

In the deep well injection concept the waste would befed into porous or fractured rocks. To protect freshwateraquifers, the injection zone would have to be well below theaquifers and isolated by relatively impermeable layers suchas shales or salts.

The increase of the total fluid volume in an injectionzone would be accomplished by compression of any fluidalready present, and expansion of the host rock. Injectionis possible at depths of several thousand meters (DOE FinalEIS, Vol. 1, 1980).

Although the overall site area has not been yet calcu­lated, it is anticipated that it would have to be greaterthan 1,270 hectars (3,140 acres) and its final size woulddepend on the maximum horizontal dimension of the injectionzone, the size of control zone around the repository, andthe total amount and type of waste to be injected (DOE FinalEIS, Vol. 1, 1980).

Grout Injection Concept

Grout injection into shale would require that liquidwaste or irradiated fuel be mixed with cement or clay andthe slurry be injected into impermeable shale formations.The fractures would have to be horizontal. Vertical orinclined fractures could result in waste migrating towardthe surface where it would pose health hazards. The groutwould set a few hours after injection thus fixing the wastein the shale (DOE Final EIS, Vol. 1, 1980).

The site would have to be composed of flat-lying shalelayers. Favorable conditions, which would bring about

33

-- No..: Lines between box.denote wane tnnsporutionbetwMln facilities

B

ShlI~rout Injtction w.ste Process Flow

Nautnlimtlon of

...--<P>---1- .......- "--:,.---of Slurry From

L......;;;.;;.;;;.:_~ Ro......-..-.SlurryAgitation

Pvmp

A

FUEL CYCLE DIAGRAM - WELL INJECTION DISPOSAL

Fuel Reprocessing Well Injection Dispo••1

1_4,,:-~:::'~F~";:"~-_..JPI~.:nil...__1-_":H!!.L~L~W!!..._~~~::::::~=-1....ctor •"-mbl_ or e OHp Wan Injection

Spent Fuel Di....mbly a Shal. Grout Injection..d Dissolution lSea Expansion Balow)

-....--<!'>--l Pn_ .......,...--Fmm

L....;...,;,;,;,";.;"":......J _nop,,",

Daap-Well Liquid Injetion w.te. Procell Flow

___..JI Grout Sheat

Figure 18. Well injection; outline of management system.A. Liquid injection.B. Grout injection.(Source: DOE/EIS-0046F, 1980).

'.

34

horizontal fracturing, are usually found to a maximum depthof 1,000 m (3,300 ft). An overall site area for groutinjection would have to be greater than 1,270 hectars(3,140 acres); the actual size would depend on the specificconditions (DOE Final EIS, Vol. 1, 1980).

Transmutation Concept

This concept is attractive because it is designed toreduce the long-term risk to the public posed by long-livedradionuclides. Spent fuel would be reprocessed to recoveruranium and plutonium. The remaining high-level waste wouldbe separated into actinides* and fission-products. The fissionproducts would be concentrated, solidified, and sent to arepository for disposal. The actinides would be mixed withrecycled uranium and plutonium, fabricated into fuel rods,and reinserted into the reactor. Numerous recycles wouldresult in nearly complete transmutation of the waste actinides.

The main problems of this concept are security andpossible environmental and health hazards due to extensiveand repeated handling of radioactive waste.

Space Disposal

Space disposal would enable the waste to be permanentlyremoved from the Earth and Earth's environment. The wastewould be packaged in special containers for insertion intoa solar orbit where it would remain for at least one millionyears.

Space shuttle would carry the waste containers to anEarth orbit from where the containers would be propelled intoa solar orbit. After a container had been properly placedin the orbit, there would be no long-term risk, as in otherconcepts. The problems inherent in the space disposal concept,however, are the risk of launch accident and failure of theEarth orbit.

The plan of the concept is shown in Figures 19 and 20.

STUDIES IN PROGRESS

Thus far the geologic studies of salt dome deposits havemade considerable progress and a selection of a site is

* Actinides Radioactive elements with atomic numbers largerthan 88.

35

ORBITAL OPERATIONS

OTV/ORBIT 0.86 AUINSERTION /STAGE

~REENTRVVEHICLE.

). _ PAYLOAD ASSEMBLY3-..-... (REENTRY VEHICLE

.~, - ~ TO BE RECOVEREDI

EARTH {1 AUI ORBITAL DEPLOYMENTI

VENUS lO.7 AUI0 ...........__

Figure 19. Diagrammatic presentation of space disposal(Source: DOE/EIS-0046F, 1980).

scheduled for March 1981. An investigation of basalt areasis also currently underway and a site selection is plannedfor September 1981 (DOE Final EIS, Vol. 1, 1980).

Investigation of Salt Deposits

Investigations of the suitability of salt deposits fornuclear waste repositories are being conducted in fourregions: Salina Salt Region, the Paradox Basin, the GermianBasin, and the Gulf Interior Region (Fig. 21). In the GulfInterior Region the study of salt domes is in progress, whilein the other three regions bedded salt is investigated. Themain reasons leading to the selection of these four saltregions were the abundance of thick layers of salt and theoccurrence of these layers at a depth appropriate for con­struction of repositories.

36

HeectorSpentFuel

Recycle I__Facilities r--l

II

UF.I.nd 1

Pu021

Note: Lines between boxes

denote w" transporu.tionbetwHn facilities

RNetorSpentFuel

Fuel Fuelproc..ing

Assemblies Fecility

PaylC*l Pr..,.tion

LaunchHLW

Solar Orbit

FUEL CYCLE DIAGRAM - sPACE DISPOSAL

(see Expansion EWow)

MinedG*»logic

RlIpOIitory

Hulls and om.TRUW.tes

ReactorSpentFuel

Note: Lines betwHnboxes dIInote WIImtransporhltion betweenfacilities.

J ~,P.~w..,.bom

Manned Flight V....

Lon in Spec~ RililUWIlMd -.d Hook LoN inlll R_lry Contllinine"e OTV, t

PIE FM:ility in Flitlht~ Cull: ....:l Ship to I- "pCooli..~ 10- V..ic...... T........

~SO'S,tt • R--.y V......

W.i;hoI Conlai_.nd"PF· .t KSC, "Flor•• 'Dr ToMI-.y S_... to UpnMd s-c- to Orbi' t80 NM,i1lcal

Sp_ MI_Ol'I Shilold e. NPPF ShultIio.1 L...1Wh Pad Mil. fl'OM E......,38' Il'OI:lifWllion

tCt."'::k .nd O-Ploy OTV, T....,., Nue'"

SOIS ....n~

SOlS, .nd R..nIO"Y V......~

hylDMI tel SOlS. R_Ityi--

OTV Pt_ SOlS. Nue...~

SOla ....NlKI_~ Hue..... P-Vl"- .,. 0_ Au

_.y fllllm Shut'" V...ide s.p.r._.nd ;. '.ytoed inlll Eentl ftNdt 0.15 All Perl.. I- Circu.., Sat... Oo1Ilt

[.bout' KMI Re1rinlod by st>uttte &c.pe Tr.;ec1DfYin __t 'MIG o.y. I..--lric 0riMt1

tAl'· InclinMionI

• lSIIunl. with R.......

OTV R-.un F.om SOlS OTV • R_n,ry VlIhOc:Ie -,-end Nue..... '"-Ytoed.nd - Re'"",, to Ground .. "-ie" in $ ......

Retu.ns to Shvttte KSC for R..... SoleI OrtNt for.'IUnPO_" Runway L... lo'V.nbAdingl

. Nuel..r P.yload PrejMretion f_i1itye • Kennedy Spece Cent., Od"teII T.end. V_idet t Sol... Cdtit I..-,ion St..- PROCESS fLOW DIAGRAM - SPACE DISPOSAL

HLW From Fuel Processing Facility

Figure 20. Space disposal; outline(Source: DOE/EIS-0046F,

of disposal management1980).

37

w Cl)

Fig

ure

21

.G

en

era

llo

cati

on

are

as

of

salt

basin

sin

vesti

gate

d(S

ou

rce:

DO

E/E

IS-0

04

6F

,1

98

0)

•

In the Salina Basin a geologic reconnaissance investi­gation has been completed and further, more detailed studywill be conducted in selected areas of Ohio and New York.No detailed investigation has yet been initiated.

In the Paradox Basin four smaller areas have beenchosen for more detailed work: Salt Valley, Lisbon Valley,Gibson Dome, and Elk Ridge: all in utah. These detailedstudies are currently in progress.

In the Gulf Interior Region the work completed so farhas led to the selection of eight salt domes for more de­tailed study: Vacherie and Rayburn's in Louisiana; Richton,Cypress Creek and Lampton in Mississippi; and Oakwood,Keechi, and Palestine in Texas. The Palestine Dome has beenfound unsuitable and eliminated from consideration. Theinvestigations of the remaining seven domes is presentlyunderway.

Investigation of Basalts

Geologic and hydrologic studies of the Hanford Sitebasalts in Washington State have been in progress since 1977.The results at hand indicate that the site may be suitablefor a nuclear waste repository.

Investigation of the Nevada Test Site

The investigation of the Nevada Test Site is limited tothe southwest part of the Site due to the limitations imposedby military testing. The volcanic rocks in the Yucca Mountainarea are currently being studied. The results indicate thatthis area may be suitable for disposal of radioactive waste.

DEPARTMENT OF ENERGY ASSESSMENT OFPROPOSED WASTE DISPOSAL CONCEPTS

The assessment of the disposal concepts (Table 4),as perceived by the Department of Energy, is discussed inthe Final Environmental Impact Statement (Volume 1, October1980) .

The mined geologic repository is the preferred conceptconsidering the ranking factors shown in Table 4. Extensiveresearch is already underway into various aspects of thisconcept.

39

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Subseabed and island disposal concepts appear to beequally acceptable. However, the Department of Energy givespreference to the subseabed concept because of severalserious uncertainties associated with the island concept,such as long-term effect of radioactivity on the geologicand hydrologic environments.

The very deep hole disposal concept ranks high and isin some ways superior to the mined geologic repository.However, some of the important drawbacks of this concept are:development of deep drilling technology, lack of sufficientunderstanding of geology at great depths, and difficulties ofmonitoring canisters containing radioactive waste. Therefore,although the Department of Energy recommends continueddevelopment of this concept, the Department considers itinferior to the subseabed concept.

The main weaknesses of the space disposal concept arerisks of accidents during launching, failure during earth­orbit phase, and possible conflicts with international law.Because of these weaknesses, the Department of Energy doesnot recommend future development of this concept.

Rock-melting, ice sheet, well injection, and transmu­tation concepts do not rank high as possible alternativedisposal methods. The weaknesses of these concepts include:uncertain ability to contain radioactive waste and inabilityto predict effects of waste on disposal sites and theirsurroundings.

CONCLUDING REMARKS

The future utilization of nuclear energy in our economywill, to a great extent, depend upon development of a tech­nology for safe disposal of highly radioactive wastes.

According to the Department of Energy assessment,disposal in a mined geologic repository is the most suitableconcept, and most of the future research and funding willprobably be directed toward development of this method. Itis anticipated that the first permanent repository will beavailable around the turn of the century.

The safe disposal of highly radioactive waste and re­lated matters have been, and will be in the future, subjectedto scientific and public scrutiny. It is hoped that thisreport will assist the citizens of our State to better under­stand this very complex problem.

41

SELECTED REFERENCES

Aikin, A. M., Harrison, J. M., and Hare, F. K., 1977, Themanagement of Canada's nuclear waste: Minister of Energy,Mines and Resources, Report EP77-6, p. 63.

Anderson, P. A., and Meyer, H. S., 1980, Dry storage ofspent nuclear fuel; A preliminary survey of existingtechnology and experience: Exxon Nuclear Idaho Company,Inc., (NUREG/CR-1223).

Battelle Pacific Northwest Laboratories, 1974, High-levelradioactive waste management alternatives: 3(5),Richland, Washington.

Bechtel National, Inc., 1979, An assessment of LWR spentfuel disposal options: Vol. 1 and 2, Office of NuclearWaste Isolation, Columbus, Ohio.

Burkholder, H. C., 1979, Waste isolation performance assess­ment - A status report: Office of Nuclear Waste Isola­tion, (ONWI-60), Washington, D. C., 28 p.

Department of Energy, 1979, Technology for commercial radio­active waste management (5 volumes), Washington, D. C.

Department of Energy, 1980, Status of technology for isolatinghigh-level radioactive wastes in geologic repositories:(DOE/TIC 11207, Draft), Washington, D. C., 127 p.

Deutch, J. M., 1978, Report of task force for review ofnuclear waste management: Department of Energy (Draft),Washington, D. C.

Energy Research and Development Agency (ERDA), 1976, Alter­natives for managing waste from reactors and postfission operations on the LWR fuel cycle, Vol. 4:Alternatives for waste isolation and disposal: Washington,D. C.

Environmental Protection Agency (EPA), 1979, Alternatedisposal concepts for high-level and transuranic radio­active waste disposal, Washington, D. C.

Gray, D. A., et a1., 1976, Disposal of highly-active solidradioactive waste into geological formations - Relevantgeological criteria for the United Kingdom: Report No.76/12, Institute of Geological Sciences.

42

Kreitler, C. W., 1980, Studies of the suitability of saltdomes in East Texas Basin for geologic isolation ofnuclear wastes: Bureau of Economic Geology, the Univer­sity of Texas at Austin, Geological Circular 80-5,7 p.

National Program for Management of Commercial High-LevelNuclear Waste, 1980, Report on geologic explorationactivities, (DOE-RL-C-14), Washington, D. C., 66 p.

Office of Nuclear Waste Isolation, 1979, An Assessmentof LWR spent fuel disposal options, Volume 1, 2, and3 (ONWI-39), Washington, D. C.

Office of Nuclear Waste Isolation, 1979, National wasteterminal storage program, Office of Nuclear WasteIsolation Technical Program Plan (ONWI-19; REV-I),Washington, D. C., 125 p.

Office of Nuclear Waste Isolation, 1979, Storage roomdesign parameters for the ONWI spent fuel disposalstudy; nine case studies in salt: (ONWI-4l), Washington,D. C.

Office of Nuclear Waste Management and Geological Survey,1980, Earth science technical plan for disposal ofradioactive waste in a mined repository: Draft(DOE/TIC-ll033 , ONWM and USGS), Washington, D. C.

Office of Nuclear Waste Management, U. S. Department ofEnergy, 1980, Management of commercially generatedradioactive waste, Final Environmental Impact State­ment, Volumes 1, 2, and 3 (DOE/EIS-0046F), Washington,D. C.

Patchick, P. F., 1980, The suitability of Palestine saltDome, Anderson Co., Texas for disposal of high-levelradioactive waste: Technical Report, Office of NuclearWaste Isolation, (ONWI-74), Washington, D. C., 35 p.

Philberth, B., 1958, Disposal of atomic fission products inpolar ice caps: IAHS Symposium.

Philberth, K., 1975, On the temperature response in ice sheetsto radioactive waste deposits: Presented at Interna­tional Symposium on the Thermal Regime of Glaciers andIce Sheets: Simon Fraser University, Burnaby, BritishColumbia.

43

Zeller, E. J., et al., 1973, A suggestion for a permanentpolar high-level radioactive waste repository: Bull.Atomic Scientists, p. 4-9, 50-52.

44

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