OF DECISIONREMEDIAL ALTERNATIVESELECTIONSEPT. 8, 1 9 8 6

fiecord of Dec i s ionl Alternat ive Selection

S ITE : Odessa Chromium I , Odessa , TexasDocuments

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Chr~ 'Al t e r n a t i v e Watero Sugary o, Remed ia, Alt.rnatl¥.o itesponsivene:-s Summary£!l£llon_ojF^ele^^

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i t ion , the act ion «l

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I 8Dat(T 1^6Regional AdministratedRegion VI

Odessa Chromium 1 (operable unit)Record of Decis ion Concurrences

The Odessa Chromium I Record of Decis ion has been revised and I concur

AHyn M. Dav i s , Director——————"*Hazardous Waste Management D iv i s i o n E. Ed lund , Chief"—————7

Superfund Program BranchHazardous Waste Management D iv i s i o n

f i t Stok e s , Ch i e fSo l i d Waste & Emergency ResponseOf f i c e o* Regional Counsel

Stanley G, Hit t , Chie lTexas Remedial Sect ionSuperfund Program BranchHazardous Waste Management D i v i s i o n

;Bonnie J. DeVos , ChiefState Programs Sect ionSuper-fund Program BranchHazardous Waste Management D i v i s i o n

SUMMARY OF REMEDIAL ALTERNATIVE SELECT IONOPERABLE UN IT - ALTERNATE HATER SUPPLY

ODESSA CHROMIUM IODESSA, TEXASSEPTEMBER 1986

TABLE OF CONTENTS

Site Location and Descr ipt ion ————-——————————»-*..««»———— \Site History ----- ————— —— -- ——— ---—————-————— —— ^—————— 1Current Site Status ----————-——-----—-----<•—*,-....—«.—.«,..... 2Exposure Assessment --- —— .,- — — ...—...-..-.*————--—— ».--. .-. . .- 6Appl icab le or Relevant and Appropriate Requirements ---,—— -——————— 6Community Relat ions *—-•-«.-----..-.-—. — •.««.-—- — .....**..«..-.....« 7Enforcement - - - - - * - - - - - - - - - - - - - - - - - - - - - - - - - - - - » - - - - - - « » - - - - - - - • . . - - • - -— . 7Alternat ive Eva l ua t i o n --------.—.. .-.-..«.. ,-. .-. .-. .-—^_-^..-. . . , . . 8Recommended Alternat ive *—-----———..——.........—————-.--——— 12

* . * ,-« . * »— — > . • . — • — • . • *o««a««d*«*v«_«B.M»-*««>w> .B*— _ . > * , . » • • • • — n >A_ i > . . * — •_««—•>« J^J

SUMMARY OF REMEDIAL ALTERNATIVE SELECTIONOPERABLE UN IT - ALTERNATIVE WATER SUPPLY

Odessa Chromium IOdessa , Texas

SITE LOCATION AND DESCRIPT IONSeptember 1986

'site area is of

' « • st (Flgure 2'n • "thonl, source of potable g r o d w a t rS I T E H ISTORY

o 4s ite was f irs t deve loped between

n d n ,Water Reso ur e e s { T DWR) Ident if iedchromium contaminat ion . A water• '

°ffers the

contaminat ion at the s ite have beeno ?9% K Th6 "3:8 BrazOS'

nOepartment of? potent ia l source of'

ODESSA CHROMIUMi

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tOCATlON MAPFOCUSED FEASIBILITY STUDYODE$SA CHROMIUM I SITEODESSA, TEXAS

TEXAS WATER COMMISS IONAUSTIN, TEXAS

•0- OIL WELLSUPERFUNO (WPACT SERVICE AREA

COWTAWUN'-TIOM PLUMEPRR PROPERTY

200 O 200 FEETSCALE

FIGURE a-SUPERFUNO IMPACTIEO '.

OOCSS*ODESSA.

WATER t >AOSTIM.T

ItfV S r«H,?? i I T guested the Environmental Protection Agencyi«»« ̂ »r 55 a "P l anned ^mova! action" to extend the city waterl ines to the affected area . In June 1984, TDKR not if ied EPA that theproposed water system extens ion did not appear feasible due to the oppos i t ionby res dents to annexat ion by the city of Odessa . With the exception ofSlri ?r f 1"dustr ia | areas' the city of Odessa is prohibi eSbyordinance from supplying water to customers outside of the city limits!In September 1984, the Odessa Chromium I s ite was added to the Nationalrf^l ^UHSt (^teS WhUh appear to P r e s en t a s ignif icant rfsk opublic health or the env ironment) . The State of Texas entered intocooperative agreement with EPA for $530,000 on September 26, 1984, to

rd ann1?.9 ̂ Remed1a 1 Inst igat ions/Feas ib i l i ty Stud i e s"1986. T 6 R

In January 1 9 8 6 , EPA and the Texas Water Commiss ion (TWC) decided toproduce a 'Focused" Feas ib i l i ty Study (FFS ) . The s i ng l e purpose of theFFS was to be tie examinat ion of poss ib l e a l ternat ive water suppl ieswhich could provide potable water to the a r ea ( s ) w i th i n the greaterfcessa Chror- ium 1 s i te where groundwater is contaminated or could reason-ably be expected to become contaminated by chromium wi th in 24 months Whi l ethe goal of EPA is to determine a plan for address ing the chromiumcontaminat ion ,„ the groundwater , the FFS placed a port ion of the fullfeas ib i l i ty itufly on a "fast tracked" schedule . By do ing so, it openedthe poss ib i l i ty of exped i t ing the supply of potable water to affectedirnSiSrrhSi«':'10' iVa1t1n? f0r c omP l e t 1 °" "f the full FS . The FFS beganin March !9St > , and a rev i sed draft report has been submitted.

S ITE ST;TUS

The surf ic ia l so i l in the s i te area is pr inc ipa l ly Amar i l l o loam.Genera l ly uu a reddish-brown, fine sandy loam which ranges in depthfrom 8 to 12 inches below grade . Below that , to depths vary ing from 18to 24 inches , the red or chocolate-red subso i l grades from fine sandyloa-n to sand,, clay, gradua l ly becoming heav i e r with depth. Ple i s tocenewindb lown sand , olaya depos i t s and a l l uv i um depos i t s under l i e the so i lsect ion. Beieatn the Ple i s tocene are Pl io-Ple i s tocene caliche depos i t s .Underly ing the cal iche are scattered eros ional remnants of the Tert iarvOga l l a l a formation composed of grave l s , sands , s i l ts and clays Thesebasal sediments occupy previous ly eroded dra inage valleys and are notpresent everywhere. Cementat ion of the sands is var iab le with in theOga l l a l a . This formation does not general ly extend to depths below 75feet in the are;.

The Cretaceous Trinity formation, the main fresh water producing aquiferin the area, underlies the Ogal la la interval. It is composed of sands andsandstones with minor amounts of si ltstone, clay and gravel. Cementationof tne Trinity in the site area ranges in degree from moderate to heavy.The aquitard beneath the Trinity formation 1s the Dockum Group of Triassicage, locally known as "redbeds." The upper unit, the Chin le formation,consists of up to 600 feet of red and reddish-brown clays and shales.Grou^dwaterThe major hydrologic units conta in ing potable water in the site area arethe Ogal lala formation at approximately 70 feet below the area and theTrinity Sand at approximately 90 feet below the area (Figure 2-2) , Ingeneral, the Ogal la la is hydrological ly connected with the underlyingTrinity and has little or no saturated thickness. A few miles to thesojt^west the Oga l l a l a has been totally eroded and within the site areais o^ly a thin remnant containing little water. Groundwater occursbeneath the site mainly in the Trinity Sand.The Hydraulic characterist ics of the Ogal la la are of greater importancelocally than the quantity of water present due to the fact that theOga l l a l a roay potential ly act as a medium throuf'". which contaminants mayenter the underlying Trinity Aquifer, Barriers to vertical movementex i s t in the Oga l l a l a as d i s cont inuous lenses of calc i te or cementedsandstone. These lenses were encountered in dri l l ing at the site andva^y from less than 6 inches to several feet in thickness. Although noperched water zones were encountered in dr i l l ing, these lenses could actlocally as a barrier to vertical migration of water.It was suspected prior to any deep borings being constructed, as part of thesite invest igat ion , that a "perched" water table may exist beneath atS0ft>e portions of the s ite area . Although some thin clay and s i l t s tonelayers and a well cemented sandstone layer were encountered above theregional water table , no water was found to be "perched" on these potentialaqu1t*rds or confin ing beds. This indicates that there is fracturingsuff ic ient to enhance downward migration of groundwater present and/orthat the layers themselves are of limited area! extent and discont inuous,Another influence on contain; nation movement seems to be the caliche layernear the sur fa ce . Sha l l ow borings indicate that it acted as a relat ivelyeffect ive barrier to the downward migration of contamination caused byleaching of the soil .teAn inventory of exist ing water wells in and around the previously identifiedarea of chromium contamination was conducted in September 1985. Theprimary goal of this work was to conf irm and refine the boundaries of the

DEPTH(FEET)0r

60

eo

100

120

140

"LAND SURFACE

SOIL, WINDBLOWN SAND, ALLUVIUM

CALICHE

SAND AND GRAVEL, OGALLALA

GROUND WATER(-60 TO 85')

TRINITY SANDSAND WITH VARYING

DEGREES OF CEMENTATION)

CHINLE FORMATION(RED CLAYS WITH INTERSPERSED SANDS)

FIGURE 2-2GENERAU2ED STftATAGRAPHJC SECTIONFOCUStD rEASiB 'UYY STUDYODESSA CHROM.JM I SfTEODESSA,TEXASPREPARED fO«

TEXAS WATER COMMISSIONAUSTIN, TEXAS

/i

plume of chromium contamination. Over- 200 wells were identified duringthe inventory, of which more than 150 were sampled and analyzed, forhexava lent chromium. The inventory covered an area extending in a radiald irect ion about half-a-mile from the known areas of groundwater contaminat ion,Fifteen wells were found to be contaminated with chromium.From the wel l inventory, several conclus ions were drawn about thecontaminat ion plume. The shape of the plume assoc iated with 4318 Brazossite has become more restricted as a result of information gained duringthe well inventory. One of the wells to the east of 4318 Brazos whichpreviously had been contaminated did not show any detectable leve ls ofchromium dur ing the inventory. Consequent ly , the southern portion ofthe plume is confined solely to 4318 Brazo s . The plume extends northwardand broadens further to the east. Based on the water level measurementsand correspond ing grad i en t , the source area appears to be 4318 Brazos ,The well at 38th and Rasco previous ly ident if ied as being contaminated , didnot show chromium in this recent survey. A well one block to the east,at 391 1 Brazos, was detected as having chromium concentrations well abovetne dr ink ing water s t andard^ This was the only wel l ident i f i ed in thestudy area south of the main plume area to have any detectab le chromiumconcentrat ions. Based on inventory results , water from the well is notused for dr ink ing water purposes and is too salty for human consumption.The well prov ides water for wash i ng and toi let purposes only at acommerc ia l e s tab l i s hment .A new area of contamination consist ing of five wel ls was identified onthe west per imeter of the wel l inventory study area . The chromiumcon tam ina t i on l eve l s ranged from 0 .02 to 0 .2 1 mg/ 1 . No readily obv ioussource of the contaminat ion was identif ied and the Odessa Chromium I Si teRI/FS or FFS was not expanded to include this area. The five wells areserving commercial establ i shments and are not being used for drinkingwater purposes . Use of the wate^ is l imited to wa s h i n g , to i let or i ndus t r i a luse .Present and Projected Contamination AreaThe e s t imated extent of chromium contaminat ion in the Trin i ty aqu ifer isshown in Figure 2 -7 . Histor ica l levels of chromium concentrations measuredin area wel ls between 1978 and 1986 are presented in Table 2-4, As seen inthe f igure , the plume extends northward from 43 18 Brazos beyond 46thStree t , Samples co l lected from the newly insta l led moni tor ing we l l s haveconfirmed the chromium contamination with in the plume and also have aidedin the closer defin it ion of the areai extent of the contamination.The con tam ina t i on beneath the 43 18 Brazos s i te is heavi ly concentrated inthe upper port ion of the Trinity. Waste water from the p lat ing operat ionsis believed to have been dumped directly on to the ground on the northerns ide of the bu i l d i ng and/or piped into storage tanks/drums which frequentlywere a l lowed to overf low. An abandoned wel l on the southeastern cornerof the bu i ld ing is suspected of prov id ing a direct pathway to the aqu i ferduring periods of substant jl disposal or heavy ra ins . Approximately 200to $00 feet to the north, the layer within the Trinity which restricts

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HISTORICAL RECORD OF CHROMIUM OCHCramATlONS(Omtimw!)

(I)——— - —— " ——————— — — ———— .-..——.— ——— . ———— -- -" • ' ___________________ HMl» \Ltlf

&-J09Q fcwdalIB 2015 tf. 46th(4)

E-!Wl Industrial Wtoterfal HurvtHntr C4)

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E-I092E-1093

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B-E-I097

E-B-J099

B-ISOIE-H07

S-III5E-IU6

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4415 W. Onmty Rd

mdcsea Hut & Bolt, 4407 W. County Rd/*^

Cuwrfng Electrtc, 4405 W. Owntr"lM.WHenry Stmtcre 2SOI W. 44thW

430B Brazos^**MR Scste 8tt Serrlce, 4313 W.

Btg State Bit Service, 4313 W. Cbtmty Rdf/*5

Ibrbo Specialities „ 4301 W. Cbmrty Rd

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, 2427 ». 42ndOofitlng Supply, 2419 W. 42nd

Twcllne, 243! K. 42ndHighland P««p, 260« W. 42nd

0.97

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TAIHISTORICAL RECORD OF CHRClWrOK OOWCKWTRATTCNS

(Contlm>«!)

_ HELL WO.

Ml 54E-H64

B-II65E-1I74

B-U75E-l

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Artco Battery* 39tl Br«zoaPalner Cbntractin-K* 3800 Rnwco

Brette Trnller PUT*, 2153 W. 39thCtewpressor Ctewponpnte, 2605 W. 42mf

•Rroifl West Otlfleld Services, 2700 W. 40thCbwpreasor Cb«ponentfft 2607 W. 42nd

Well I9f Golder Ave.

<0.02(7) <0.020.55

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(3) Absndoned(6) Shown In Figure 2-7.(5) Sampled MsyB 1966.(6) Sampled October, 1985.(7) B. Psiner angled in |1!oTe«!»rt 1978. Cr - 12.0

III downward migration of the contamination below 100 feet, no longer Ispresent and the contamination is free to diss ipate throughout the entireTrinity sect ion.Sediaents, soils and rock at 4318 Brazos show contamination from thesurface to approximately 10 feet and again at around 53 feet. ThisIndicates that waste fluids generated by the activities there and conta in ingchromium and other heavy metals were spilled on the surface, The contaminationthen entered the soils through a septic tank drain field, traveled laterallyalong the upper surface of the shal low cal iche layer, downward throughfractures in the cal iche, or through the abandoned open 'well bore on theproperty, to the Ogallala Formation and ultimately to the Trinity Aquifer,In addition to these contaminant pathways, it is possible that heavy metalcontaminat ion spi l led on the surface was carr ied by surface water runoffinto the abandoned open wel l bore on the property, and then, to the zone ataround 50 feet.Over the entire area of the Odes s sa Chromium ! s i te , the regional groundwatergrad i en t 1n the Trinity is to the north and northeast at between 10 and15 feet per mile. Contaminated water entering the top of the Trinityaquifer spreads out horizontally in a northerly direction. Vertically,it can be presumed that the contaminants are init ial ly "perched" in theupper port ion of the Trin ity unt i l the hard streak at about 100 feetdisappears. The contaminants then move progressively deeper with increasingdistance from the source in this relatively homogenous aquifer,As s^Dwn in F igur e 2 -7 , there appears to be one major plume of chromiumcontamination in tne Trinity within the site area. Based on the start ofmanufactur ing or process operations, and historical sampling data (TWCrecords ) , it is pos s i b l e to est imate contaminant migrat ion rates for thispiThe northern extent of tne contamination is beyond 46th Street, more than1 100 feet beyond tne source area . Cons ider ing that the plating operat ionsbegan d i spos ing of waste^ater at the 43 18 Brazos locat ion, beg inn ing between14 and 2B years ago, the average velocity of the contaminant migrationcan be estimated at between 45 and 80 feet per year,Using values obtained front a pumping test performed dur ing the RI,calculated migration velocities for Trinity water range from 50 to 100feet per year, Empirically derived rates for contaminant migration withinthe Tr in i ty appear to be reasonably s imi lar . A conservat ive project ion of100 feet per year has been used for es t imat ing the maximum extent ofcontamination,

II

EXPOSURE ASSESSMENT/APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTSThe public health evaluation process as described in the EPA DraftSuperfund Publ i c Health Evaluat ion Manual (December 18, 1985) states thatthe projected concentration of the indicator chemicals at the exposurepolrrts should be compared to appl icable or relevant and appropriate require'ments. The National Contingency Plan (NCP) defines what 1s consideredpotential ly "app l i cab le or relevant and appropr iate" ; the federally setdrinking water limits are included in the l ist , Comparison of the datacollected in the RI to health guidel ines aids in determining whethera remedial response action Is necessary to protect the publ ic health andenvironment .For the Odessa Chromium I site, the receptor exposure points are assumedto fre the water supply we l l s . The indicator chemical is chromium and theappl icable or relevant requirement Is the Federal Dr i n k i ng Water Standardpromulgated under the Safe Dr ink ing Water Act (SDWA) .During the Remedial Invest igat ion , two contaminants, z inc and chromium,were found at levels above the detection l imits of C .05 and 0 .0 1 mg/1respect ively in the exist ing supply wel ls tested. All reported valuesfor z inc are below the EPA secondary maximum contaminant level in dr ink ingwater of 5 mg/1. Zinc at these concentrat ions is not considered a publ ichealth concern and is excluded from further cons iderat ion in the evaluat ionprocess.However, reported chromium concentrat ions may be s ign if icant from a pub l i chealth perspect ive . Twelve out of fifteen contaminated wel ls sampleddur i ng the RI had chromium leve l s at or above 0 .05 mg/1 [the maximumconcentrat ion l imit (MCL) ] , Nine of these twelve wel ls had values at orabove 0 , 1 2 mg/1 [the proposed Recommended Maximum Concentrat ion Limit(RMCi ) Federa l Reg i s ter , Nov. 13, 1985 ] , a l though two were abandoned. SeeTable 2-3 for data and summary s ta t i s t i c s .Since chromium has an app l i cab le re levant and appropriate requirement,i . e . , the EPA Dr ink i ng Water Standards , that requirement is used as thebas is for tne target concentration. Consequently, the pub l i c healtheva luat ion is complete when the concentrat ion of chromium in the wel ls iscompared to the standard.The wel l s wi th values above the MCL of 0 .05 mg/1 are not su i tab le for useas a l ifet ime dr i n k i ng water supply and an alternate water supply isindicated.As required by the SDWA, EPA acted quick ly fo l lowing the passage of theSDWA in pub l i s h i ng Inter im Primary Dr i n k i n g Water Regu lat ions . Regu lat ionswere estab l i shed for ten inorganic chemica l s , six pest ic ides and twomicrob io log ica l ind i cators .

%A£U 2-3TOTAL CHEOKItm VALOBS X)*C5 KG/L (KCX)

HEPORtKD POE KIXSTUtC 1UTSR SUPPLY HKUSSAHPLKD DOtlKG KXroccssD PEASISIUT? STODT

ODESSA CSKCttXCm I SITEODESSA, fSUS

WtLt NO. USETOTAL

CHROKIUM VALUE

E1046 ( 2 )

£ 1 1 1 5fj*\B 1065 < 2 )

£ 1086 ( 2 )

EiOS6A ( 2 )

E1090 ( 2 )

E1092 ( 2 )

E 1093 ( 2 )

2 1094 ( 2 )

E 1 1 1 7E 1 1 5 4EX10D ( 2 )

Co&mercialCosaercialCoemerc-.ialCommercialCottmercialCommercialCoEffiercialCommercial

CotamercialCommercialCoBmercifllCoaaoercial

———±=tU-> _ NOTE(S)0 .07 ,0 .0? ( 0 .060 .07 ,0 .04 <2 > Ouuidc of «tudy «rea

5 * 1 , 4 . 714 ,0 , 1 3 . 6l.«, 2,90 . 6 , 1 . 13 . 4 , 2 , 9

° '39 Abandoned1 '9

0 . 2 1 , 0 . 1 6 Ouuide of study area0 .55 ,0 ,55

* • ! Ak^-J _ _ . j

SuaffiAry Sta t i s t i c s :>0 .05 »g/l H -2J , X -2 .6 1>0 . 12 Bg/1 »- 16, X-3 .2 11. Miligramfi per l iter.2. Shown on Figure 2-7.3. Below MCL.

The Maximum Contaminant Level MCL) for total chromium under the Nat ionalInterim Primary Drink ing Water Regulat ions was set at o"o5 mq/1 inand was based on the 1962 Publ ic Health Service l imits

Chromium is c lass i f i ed in EPA ' s Guidel Carc inogen ic Risk

TSLV "proposed for total chromium, i . e . , Cr HI plus Cr VI in dr ink Inq Sater(Federa l R^ajstex. Nov . 13, 1 9 8 5 ) . o r i nK i n g waterpr°pOSe a MCL as to the RHCL as

rf i l l probably be proposedl ikely be set at or above the~RMC[ iimit" of 6^2 mg/i.' ^ MCL WlU m°$t

COMHJMTY RELAT IONS

lttaSchmeni°B}!n i "' C°mpl6ted after thG P u b 1^ comment per iod . (SeeENFORCEMENT

-rssi;\r , s SMSs.

ALTERNATIVES EVALUATIONTne presence of chromium in water supply wells at levels above the maximumcontaminant level established under the National Interim Primary DrinkingWater Regulat ions represents a threat to present and future public healtnand welfare. A response to the release of chromium in the groundwater Isappropriate in accordance with the National Contingency Plan (NCP) , 40 CFRPart 300. The response act ion toward mit igat ing the release of chromiumis currently under study in accordance with the NCP, 40 CFR 30U.63(d) .A discrete part of an entire act ion that will decrease the pathway ofexposure is known as an operable unit. An operable unit, 40 CFR 3£ )0.68(c ) ,may be implemenced before final remedial action is selected for a site.The cleanup of groundwater contamination plumes is so t ime-consumingthat a need for alternative water supply is often re-quired to protectpubl ic health and welfare until the completion of the remedy, Alternatewater suppl ies can be provided as an operable unit of the entire act ion.To satisfy NCP requirements, including the requirement thai the operableunit be cost-effective and consistent with a permanent remedy, 40 CFR30U.63( c ) (3 ) , a FFS was completed for the Odessa Chromium I site. Thepurpose of the FFS was to develop and evaluate alternative water supplyoptions in terms of cost , acceptable engineering practices and effectivenessin contr ibut ing to the protection of public health, welfare and theenvi ronment.The FFS was written in accordance with current EPA guidance, specif ical ly"Guidance Document for Provid ing Alternative Water Supplies" (Draft) and"Guidance on Feasibi l ity Studies under CERCLA". Seven water supplyoptions were identified for evaluation in the FFS:

o No Act ion (Alternat ive I),o Deve lopment of surface water supply (Alternat ive II) ,o Development of an oversized community storage facilityto compensate for loss of ex i s t i ng system capacity

(Alternat ive III) ,0 Blend ing the contaminated port ion of the water supply

with uncontaminated water supplies to reduce contaminantsto safe levels (Alternative IV ) ,o Removal of contaminants via treatment (Alternative V),o Development of a new water well field outside the areaOf contamination (Alternative VI ) , oro Connect ion with an exist ing municipal or private supply

(Alternative VI I ) .

9These .even alternatives were subjected to an initial screening processto narrow the list of potential remedial act ions for further detai ledanaVsts (40 CFR 300 .68 ( g } ) . The three broad cr i ter ia used in the initialscreening are cost , acceptable engineering practices and effect iveness .A brief descript ion of the alternatives and summary of the in it ia l screen ingfol lows,No Action (Alternat ive l_)A new source of potable water would not be supplied to the area underthis alternative. The threat to the public health and Environment wouldremain unchanged since the affected people would continue to have theirhealth threatened due to use of chrom:um contaminated water. This alternativefa:1s the initial screening cr iter ia of effectively protecting the publichea- tn and welfare.Oeve' opnent .of ._Surface__Water Supply JAJ ternati ve 11 )The development of surface water (r ivers , streams, lakes, ponds andreservoirs) would be considered under this alternative. The potential fordeveloping a new surface water supply from streams, lakes or rivers isnonexistent in the site due to the lack of a reliable year round source.The possibil ity does exist of purchasing water from the Colorado RiverMunic ipal Water Distr ict which maintains storage reservoirs one-half mileeast of the Odessa Chromium I s i te . This alternative will be expensive andd iff i cu l t tobe subjected arrange but is effective and feasible . Alternative II wasto a more detailed analysis.Development cf a^ Oversize Community Storage Facil ity (Alternative III )

j. ve_n.d \g 9 of. Con t a ml n ate d W'a t Le T__W i t h jjnc ; o ntarri ii n at e d Wa t e F~j A 1 1 e r n atTy e 1 V )these a l ternat ives have two basic prerequisites: a central distribution

syste^ and an exist ing, low yield supply of potable water which could bepulped into a storage facil ity. Neither of the prerequisites is met atOdessa Chromium I and botn alternat ives are eliminated from furthercons iderat ion .

v i a i A 1 tern at i y_ e_V )A treatment process to remove chromium from the groundwater to bring thewater wi th in the dr ink ing water standards is cons idered in this a l ternat iveThis can be accompl ished by treatment at individual wel ls or at a centraltreatment plant. Three treatment methods, precipitat ion, ion exchange andreverse osnos i s , were cons idered. Prec ip i tat ion and reverse osmos i s ,whi le capable of removing most of the chromium, would not reduce theconcentrat ion below the drink ing water standard of 0 ,05 mg/1 . Only ionexchange is a viable treatment process . Ind iv idua l household ion exchangeunits are costly and require sens i t ive water quality control , A central1on exchange system offers the fewest number of ser ious drawbacks and wascons idered in more deta i l ,

10Development of a New Wel l Fie ld (Alternat ive VI)Under this a l ternat ive , a supply of water could oe developed by dr i l l i ngnew we l l s away from the contaminated area and br ing ing the water to theaffected area. Due to land use restr i c t ions , ownership restr ict ions andlocat ions of poor qual ity water, only the area south of Yukon Road andeast of Ector Avenue, 3 mi les east of the s i te , can be considered for anew well f ie ld. This a l ternat ive wi l l be expens ive but is feas ib le andis cons idered for further analys i s .Connect ion with an Exist ing Hunicipal_ttater Supply (Alternative. VI I )Th i s a l ternat ive would cons i s t of the extens ion of the city of Odes sal ines beyond the city l imits into the affected areas . The city of Odessais forbidden by ord inance from supplying water to customers outs ide thecity l im i t s . Annexat ion of an area is required in order to extend waterservice but res idents of the affected area have expressed oppos i t ion toannexat ion . The a l t ernat ive does appear feas ib le in sp i te of this problemand is cons idered for further ana lys i s ,DETA I LED ANALYS ISThe pre l iminary s c reen i ng process has reduced the seven opt ions fora l t e rnat ive water suppl ies down to four opt ions :

o Deve lopment of a surface water supply (Al t e rna t i v e II)o Removal of contaminant s via treatment (Al te rna t ive V)o Deve lopment of a new wel l f ie ld (A l t e r n a t i v e VI)o Connect ion with an ex i s t i ng munic ipa l water supply system

(Al terna t ive V I I )The pre l iminary screen ing process has also shown that for Alternat ive IIand Alternat ive VI cost s av i n g s can be rea l ized for both by combin ingcer ta in port ions of the water supply system for the Odessa Chromium I andI I pro j ec t s . Further d i s cu s s i on wi l l address th is cond i t i on .Tne detailed analysis of the final four alternatives follows the outl ineof 40 CFR 300 .63 ( h ) wh ich requires an extens ive eva luat ion of the potent ia lp lan s . This eva lua t i on inc ludes an eng ineer ing ana lys i s , analys is ofIff lp lementabi l i ty , cost ana lys i s , env i ronmenta l protect ion ana lys i s ,publ ic hea l th analys i s and regu latory/inst i tut iona l analys i s . The costana lys i s i s summarized in Tab le 6- 1 . Table 6-2 gives the averageres ident ia l monthly water bi l l that can be expected under each plan.The detai led analys i s of the four plans is summarized in Table 6-3 .Important f ind ings from the deta i led analys is of each a l ternat ive fo l lows .

tAJLE $-COST COKPABISOH OF

FOCOSED FIAStEXLlTT STTOTODESSA CBXOKHW 1 SXTB

ODESSA, TEAS

_ ALTERNATIVEII Surface Water

!XIa Combined

Surface WaterV Xoa Exchange

VI New Well FieldCombinedHew Well Field

VII Municipal Water 2 4 7 , 9 2 0

0 4 HPRESENT

$ 404 ,500 $ 82,400 $ 626 ,750

3 0 9 , 1 5 0

$ 1 , 0 3 1 , 2 5 0372,400852,900

1 , 8 1 9 , 3 5 01 .759 ,250

6 7 , 1 5 0302,7501 15 ,25059 ,000

5 10 ,7502 ,302 ,750

876 ,600448 ,750

883 , 1 503 , 155 ,6502 ,695 ,9502,208,000

357, ^70

. t ea : (1) O&H - Operat ions and Maintenance(2) Presen t Value, based on IS «*nrc in* Atfor OiH. y § 10X disGouat «t« and OZIII ft HVrL6

t

t0,U1 °f/aplUl C O S t S «d P'««" v«lue of WM.(4) 0 4 M cost, assumed equal to the annual total of nonthl* »««paid by property owners in the iapBcted .rea.

7

IIABLK «-2

COST PIE. THOOSAHD GALLONCOMPARISON OF AmRHATIVESFOOTED nASlllLlTI 8TODY

ODESSA CHEOKIQH I SITSODESSA, tttAS

ALTERNATIVEII Surface Water

Hi CombinedSuffice Water

V Ion ExchangeVI Hew Veil Field

Via CombinedHew Well Field

VII Municipal Water

COST ($)/THOUSAND GALLONS**>14 ,62

3 1 .5620.456 .44 < 3 >

7 , 7 0 / 1 . 3 5

AVERAGERESIDENTIAL HOKTHLY

(4 )

2 1 9 . 2 798 . 13

473 .39306 .66

96 .67

37 .88

Mote : (O Costs are annual 06H costs and annual water consumption inthousands of gallons.C? v Sased on f ifteen thousand gallons.(j) Based on combining water consumption for both Odessa I and Odessa

II and O&K costs for Odessa I and Odessa II since residents wouldi>e part of the isme water Association.(4) For first two thousand gallons, $ 7 . 7 0 ** l 1 1 .35 per thousand

gallons of remaining portion, plus A 501 surcharge.

TABLR «-> .«iM?*»T9fflt or

Sorfvr?_rOTLIC REfttTW COHCEMfSWo

corns* cnrowiiw i SITKonrss*, TTJ AS

TfCRWICALShort tern conntructton

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rvat* wtth

to flnRttrr that contam-inant* properIf r*-

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fvp*rt

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coftoerurtfon

tech-pquE

O(M-r/ttlonai

for

lH(fh wmthtf vst^r frtSX•mt mtntaCnlnK ft WKcrr•wvortfttton. Al*<», vilttr^atwent conttne* tofunction fn

wtte-r Ktfftt •onttltr *»t«T Mil*mf pmble* of for«tnit

technology rconnect ton to

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r«»*fn»with • v*ter m*aOf-1 at ion.

U*t»ttftf forIOR «mt«r vupptywtth a mtrr***Qct*t(an.«tf to

11Development. of Surface Water Supply (Alternat ive II)The water supply of the Colorado River Munic ipa l Hater Distr i c t is(CRMWO) adequate, rel iable and of good qual ity. A water assoc iat ion orpr ivate corporat ion wi l l be necessary to own and operate the treatmentsystem and distr ibut ion system, The total capital cost is estimated at$372,400 with annual operation and maintenance cost of $67, 160. Thepublic health wil l be well served and no adverse environmental impactswojld take place due to this a l ternat ive . The city of Odessa has rightof first refusal with CRMtfD thereby complicating negot iat ions for thewater,

.CpJ!|tani1_na_nts via. . Treatment (Alternative V)A central system ut i l i z ing ion exchange would require at least threewater wel l s purcping contaminated water from the affected area to thesystem. The treatment system would be soph i s t i cated and require tra inedpersonnel work ing for a water assoc ia t ion to run and mainta in the equipmentThe capital cost est imate is $852 *900 with operat ion and maintenance costest imated at $302 ,750 annual ly . A major negat ive aspect is the requirementof the three water wel l s pumping from the contaminated area. The character-i s t i c s of the aqu ifer would dictate that the we l l s be spread throughoutthe plu"*e area caus ing three pumping centers with corresponding cones ofdepres s ion l ead ing to further migrat ion of the contaminants,De_veUip^ent_of a New Wel l F i e l d (Al ternat ive VI)The 100-acr e tract env i s i oned for th i s a l ternat ive reportedly conta in senough go:>d qual i ty water to meet the demand of the Odessa Chromium 1s i te . Va luab l e water r ights would need to be purchased and a treatment/d i s t r i bu t i on system constructed, The est imated capital cost is $ 1 , 7 5 9 , 2 5 0with annual operat ion and maintenance cost of $b9 »000. No adverse env i ron-mental impacts would occur and the publ ic health would be well served bytn i s a l t e rna t i v e .Con nee t i on _wi t h_a n_Ex j s t i ng Mun i c i pa 1 Water Supp 1 y . (Alternat ive V _I_.1_̂This is the only a l ternat ive which cons iders the purchase of treatedwater rather than raw water . The city of Odessa has an adequate supplyOf gooJ quality water which more than meets publ i c health requirements.The extens ion of the city water l ines is simple^and inexpens ive at $247 , 92Uin capita l cost with annual operation and maintenance cost of $ 14 ,350 .No adverse environmental impacts would occur* The city policy of non-serv ice to areas outside of the city l imits is a major restr ict ion butthe city of Odessa has Ind icated a w i l l i ngne s s in the form of a March 25,1986, city reso lut ion to consider a specia l extens ion of city water tothe s ite area.

12RECOMMENDED ALTERNATIVEThe National Contingency Plan [40 CFR 300 .68 ( 1 ) ] requires EPA to selectthe cost-effect ive remedial alternat ive that effectively mit igates andmin imizes the threat to and provides adequate protection of publ ic healthand welfare and the environment, Furthermore, the selected remedy mustattain or exceed applicable or relevant and appropriate Federal publichealth and environmental requirements that have been Identified for thesite. The four alternatives under consideration meet this requirement byreducing the chromium levels below the maximum contaminant level of 0.05mg/1, EPA must select from the four alternatives the plan which iscost-effect ive. EPA recommends that Alternat ive VII , Connection with anExi s t ing Munic ipa l Water Supply, be selected as the cost-effect ive a l ternat ivefor the Odessa Chromium I s ite . This a lternat ive consists of the extens ionof the city of Odessa water l ines to the affected area and subsequentsupply of water from the city. Deta i l s on the water line extens ion areprovided in Figures 5-9 and 5-10.In first analyzing the cost of the alternatives, the recommendedalternative is clearly the advantageous plan. The numbers in Table 6-1translate into considerable savings if the extension of municipal waterserv ice is implemented over the other three alternat ives. A savings of150S to 780% is real ized by Alternat ive V I I . The property owners wi l la l so have nuch lower water b i l l s under Alternat ive V I I .In terms of effect iveness , all the plans meet the goal of supplying waterthat will protect the public health and welfare. Only Alternat ive VIIsupplies treated water without the need for construction and operation ofa treatment system. This is an advantage for the extension of municipalwater service.Inst itut ional drawbacks are present 1n all the alternatives. The purchaseof surface water or water rights in Alternat ive II and VI wi l l be d iff i cu l t .The operat ion of a water assoc ia t ion as ca l l ed for by the three othera l t e rna t ive s wou'M be a burden to the people in the affected area . Theseinst i tut ional issues are not present in the recommended alternat ive, howeverthe extens ion of the city's water lines wil l require an exception to therules governing water supply across city l imits. This problem has shownto be solvable due to the cooperative spirit of the city of Odessa,giving Alternative VII another advantage over the other plans.In summary, £PA recommends the extension of municipal water service tothe affected area of the Odes sa Chromium I s i te as the cost-effect iveremedy for this operable unit of the project . The est imated cost is$357 ,070 and time o' f implementat ion Is 9- 12 months.

1

STREET

_PBpgpSE.D. WATER .UN*5

MlTEft.fr«r CITY of ODESSASTANDARDS

MOB^E HOMEOF

RESIDENCE

SER 1

hS/4

CONN,SE*V/. ./ •CONNECT TO EXISTING HOUSE

/DISCONNECT HOUSE FROM*- WELL SYSTEM

WATER WELL

F I G U R E 5- 10T Y P I C A L

PROPOSED WATER SERVICECONNECTIONS

FOCUSED FEASiBIL ITV STUDYODESSA CHROMIJM t SITEODESSA, TEXAS

TEXAS WATER cOww iS 'ONAUSTIN, TEXAS

13ScheduleThe schedule for the des ign and construction of the alternate water supplyat the Odessa Chromium I site is currently dependent upon reauthor izat ion ofSuperfund. The des ign phase of the project wil l begin as soon asfunding becomes ava i l ab l e , e ither through reauthorizat ion or a continuingresolut ion. When funding is ava i l ab l e , the des ign and construct ionwill take approximately 12 months to complete.

ATTACHMENT A

TEXAS WATER COMMISSIO

Paul Hopkins, ChairmanRalph Homing. CommissionerJohn O. Houchins, Commissioner

-- , .— ~£l : ~.\J• - .tarry ft. So war'd,* Executive Direclor

James K. Rourke. Jr., General Counselr 1 ' •* • • ii .». *. —•-1 - '* • 11 • rj t ? A Lii^' j

Aucust 21, 1986

Mr. Dick Whittington, P .E .Regional AdministratorU. S, Environmental Protection Agency .-'Region VI1201 Elm StreetDallas, Texas 75270Attn: Mr. Paul SieminskiRe: Odessa Chromium I andOdessa Chromium II Superfund sitesDear Mr. Whittington:This is in response to your letter of August 5, 1986 whichrequests our comments and/or concurrence with regard to theproposed remedy for providing an Iternative drinking watersupply to the affected areas at the Odessa Chromium X and IISuperfund Sites. The draft Summaries of RemedialAlternatives Selection recommend that connection with anexisting municipal water supply be selected as the costeffective alternative for the two sites. This alternativeconsists of the extension of the City of Odessa water linesto the affected areas and the subsequent supply of waterfroit the City. A public meeting was held in Odessa onAugust 13, 1986, to discuss the various methods of providingan alternative drinking water supply and to receive commentsfrom the public. . , . , .The Texas Water Commission has no objection to EPA'sselection of the proposed remedy for providing a potablewater supply to the affected areas at the two sites.If you have any questions, please have your staff contactGreg Tipple of our Superfund Section at 5 12/463-7798.Sincerely,

Larry R. SowardExecutive Director

P. 0 Box 13087 Cap'to! Station • Austin, Texas 78711 » Area Code 512"J63 7898

I**»II

ATTACHMENT B

COMMJMTY RELATIONS RESPONS IVENESS SUMMARY ON POTENTIAL REMEDY MODIFICATIONODESSA CHROMIUM i 4 U, TEXAS

This community relat ions respons iveness summary is divided into the fol lowingspr t i r tnc ;

I,ii

Overview - This sect ion d i scusses EPA' s preferred alternative forremedial act ion , and likely publ ic reaction to this a l ternat ive .Background on Community Jnvol_vement anij Concerns - This sectionprovides a br1e f histo ry o f communTty interest and concernsra ised during remedial p lann ing act iv i t ies through a Feas ib i l i tyStudy at the Odessa Chromium I & II s ites.

I I I . SufTtnary of Major Comments Rece ived,During the Pub l i c Comment Per iodand^the^EPA Responses to. _ the Comments *IV. lng Concerns - This sect ion descr ibes remain ing community

concerns that EPA and the PRPs should be aware of in conduct ingtne remedial des ign and remedial act ion at the Odessa ChromiumI £ II s i t e s .

I. QVERV1JLWIn the presentation for the public meeting on August 13, 1986,The EPA discussed the alternat ives developed for Implementation ofa correct ive action which addresses an alternate water supplyfor the Odessa Chromium I A II sites and adjacent and nearbyres ident ial propert ies .Based on the Remedial Inves t igat ion and the analyses performed 1nthe Feas ib i l i ty Study, the EPA proposed to extend the cUy ofOdessa ' s water supply system to affected households. This alternative,if implemented, would provide negotiated agreements between theCity of Odessa and consumers for extending the city-water system tocu ^ent well users and for the construction of a water d i s tr ibut ionsyste^. Comments from local off i c ia l s and res idents favored thisopt ion, provided that the impacted a^ea would not be annexed to theCity of Ode s s a now or in the future.The comments on the four a l t e rna t ive s , along with EPA ' s responseto each, are presented later in this document.At this t ime, the EPA has presented the f ind ings of the alternate watersupply study only. The overall study on the groundwater contaminationat the Odessa s i t e s , inc lud ing remedial a l ternat ives , wi l l be completedlater th i s year, wi th publ ic comment to follow.

I I . HA;OR CONCERNS AND ISSUESOdessa ChrorniunMCommunity interest , h i s tor i ca l ly at a low leve l , in the OdessaChromium I s i t e , dates back to November 8, 1978, when the ownerOf a domest ic water well registered a complaint with the TexasDepartment of slater Resources (TDWR) - now known as the TexasWater Commission ( TWC) . This local resident complained thatthere were odors and an "oily" f i lm present in the water comingfrom his we l l . In 1979 , a water well at another part i cu lar res-idence was inves t igated and found to be heavily contaminated with. , . chromium*. . . . . . . . ,Odessa Chromium IIA low level of community interest has a l so existed historical lyat the Odessa Chromium II s ite . Publ ic awareness first surfacedin 1977 , when the TDWR investigated the area and found heavymeta l s 1n three local water wel ls .Several local industr ies were suspected as poss ib le sources ofcontaminat ion . These Industr ies generated chromium-contaminatedwastewater as a result of metal plat ing act ivit ies and cleaningrad ia tor s . '•

Both the Odessa Chromium I & II s ites were added to the Nat iona lPr ior i t i e s List in October 1984. Both sites are located outs ide

the city limits of the City of Odessa in Ector County, Texas.The approximate population of the city 1s 135,000 residents* Thetwo sites are surrounded by a few small industrial bus inesses ,s ingle family res idences , a motel, a church, a small city park ,and several mobile home communit ies. Approximately 550 - 600 residentsare affected by the two sites. These residents are not served by theCity of Odessa municipal water system. The vast majority are onbottled water, and, whi le they do not part icularly object to beingput on the City of Odessa water system, they strongly object toannexat ion by the city and the subsequent encumbrance of city taxesand fees,ACTIVIT IES TO EL1C1TJ.NPUT:_AN&_ADDRESS. CONCERNSAfter preparat ion and submitta l of a hazard rank ing package foreach s ite, the TDWR in it iated communications with the City ofOdessa, in order to determine the best means avai lable to providean uncontaminated supply of drinking water to the residents inthe Odessa Chromium I area,On Apr i l 25, 1984, d i s cu s s i on s were held in Odes sa with affectedresidents in the Odessa Chromium I area to determine theirfeelings and wishes with regard to annexation. The overwhelmingsent iment of res idents present at this meeting was againstannexat ion .Oi-s ite discuss ions were held concerning Odessa Chromium II onOctober 9-10, 1984, During these discuss ions the residentsexpressed the following concerns:

1 . Local hea l th o f f i c i a l s were concerned that there werenot any legal standards for d i sa l l ow ing heavy metals indrinking water,

2. The same health off i c ia l s wondered if some of the res identsnear the s i te were unknowingly dr i nk i ng contaminated waterfrom smal l wel ls that had not been tested.

3. One resident was concerned that water used by both a churchand a small city park near the site might be contaminated.

On January 10, 1985, a pub l i c meet ing was held concern ing OdessaChromium !I. Primary concerns at this meet ing focused on the.avai lab i l i ty of a potable drinking water supply. At that time,some residents who were providing their own bottled water becauseof contaminat ion in the ir res idence we l l s , were interested inthe poss ib i l i ty of EPA provid ing a bott led water supply as anemergency measure unti l a more permanent remedy could be studiedand determined. At this meeting, there were additional residentswho had contaminated water wells and were not on bottled waterwho wanted EPA to provide water.Subsequent to complet ion of the Feas ib i l i ty Study for an a l ternatewater supply, the EPA held & public meeting in the Odessa City

Counci l Chambers on August 13, 1986. During the public meeting,the Environmental Protect ion Agency summarized and explained theresults of all previous investigations, with particular emphasison results from the alternate water supply Feasibility Study.The EPA described the various corrective measures being consideredby the Agency for the res idents affected by the s i tes , andoutl ined opportunit ies for public involvement . The EPA expla inedthat the goal of the EPA at both the Odessa Chromium I and IIsites 1s to implement a corrective action which addresses thegroundwater contaminat ion. The process lead ing to the groundwaterc leanup is t ime-consuming; therefore, to protect publ ic healthuntil completion of the entire remedy, EPA decided io explorealternate water supply options for those people in the area withcontaminated wells.EPA d i s cu s s ed its proposed a l ternat ive , extens ion of Ode s s a ' s watersupply system to impacted persons , at the August 13 meeting andreceived comments concerning this alternative and the others consideredin the Feasibi l i ty Study, The overwhelming sentiment of res idents atthe meet ing was the ir oppos i t ion to annexat ion by the City of Odessa .

III. SUMMARY OF PUBLIC COMMENTS RECEIVED DURING PUBLIC COMMENTPERIOD AND AGENCY RESPONSES.The pub l i c comment per iod on the Focused Feas ib i l i t y Study for theOdessa Chromium I and II Superfund sites opened on July 30 andclosed on August 27, 1986. A public meeting was held on August 13,191 , in Odessa , Texas with approximately 40 people in attendance;8 peop le spoke, Representat ives for the PRPs at each s i te and 7local res idents submi t ted written comments dur ing the commentperiod. A summary of these comments is provided below.Comment #1One person asked that the proposed water supply system be extendedto include Golder Avenue (400 feet west of current proposal,). Theextension was requested due to high levels of saltin the re s i d en t ' s we l I s .EPA Response to Comment jlTexas Water Commi s s i o n suggested , dur ing the publ ic meet ing, thatthe commentor contact the Texas Ra i l road Commiss ion as they have theregulatory jur i sd ict ion of products which result from the productionof oil and natural gas such as salt water ( i .e . sodium chlor ide) .EPA cannot cons ider extending the water supply to this area becausethere is no evidence that the material found in the commentor's wellis hazardous nor 1s the location of the indiv idual ' s well within thealternate water supply boundary.

Comment J2

"* the for theResponse to Comment 12

ERA prefers that part ies respons ib le for contamination of siteperform the cleanup. Potent ia l ly Respons ib le Part ies (PRP s )tes ̂ he e6 arti^^T ChPO"iSf ' and the *£* *" in nsues, inese parties have been not if ied that they may undertakeor part ic ipate in, the chosen remedy. If they dec Hne invol™tin the remedial act ion , EPA win proceed « th the nplemenmfon of

enforcement aci lllTSX nicestComment 13Two wel l s located at 5329 Andrew Highway (Odes sato li.H the vert ical '

EPA

The Agency wi l l soon complete an overal l study of the s ites to: s H? ?»?lti ?« Ml ° e remedia act1on to be taken at thes ite . In the meant ime, there should not be s ign i f i cant addit ion. !the QUa lU^ Of the Trfn1^ Aq er fro^ ese;u the u nP l uS9ed wells may be of further value to

Commerit 14

to ,total annual usage ofto Comment 4

i th in the two areas?

and prevent other areas from becominComment

. ReAPP_n 3<L-tP,- Comment 15The Cente. * for Disease Control has determined through studies, thatin the occupational sett ing chromium dust has been found to be acarcinogen when inhaled. Health effects from chromium 1n watersupplies were extrapolated from information obtained from theoccupational studies, and frorn animal studies where the animals wereinduced with water containing elevated levels of chromium. Fromthese studies there appears to be increased body burdens ( i .e .l iver, kidney) from drinking chromium contaminated water. However,the studies have not confirmed that chromium 1s a carcinogen wheningested,Comment 06Since the majority of the local residents have found other ways ofobtain ing potable water ( i . e . bottled water) , why would this currentarrangement not cont inue to be sat i sfactory?EPA Response to_ Comment ,_#6The Agency does not know exactly what percentage of households aredr ink ing bottled water. As long as wells provide potable water to thetaps of individual households, there is an unacceptable risk that peoplwil l dr ink contaminated water .Supplying bott led water, over a 15 year de s i gn l ife, would be labora ̂ d cost in tens ive ; therefore , was not cons idered a v iab le alternative.Comment *7Wil l the proposed action be the final cleanup at the site, if nothow is this remedy consistent with a final remedy?EPA Response tp_Cpmment _j_7Tne cleanjp of contaminated groundwater plumes is so time-consuming ( 10-15 years) that a need for alternative water supply 1s often required toprotect public health arid welfare until the completion of the remedy.The extension of the municipal water supply through the impacted area* ofOdessa Chromium 1 and II is not the final remedy and wil l become part of amore comprehens ive remedy at a later date. A final remedy will be proposedfo l lowing the complet ion of the Feas ib i l i ty Study (40 CFR 300,68 ( i ) (3 ) ) .Comment f8Objections were raised to the providing alternate water to commercialfaci l it ies within Odessa Chromium I study area,

EPA Respons e t j>__Comme^n it J8The Odessa Chromium I study area is composed of 44 lots of which 23 areres ident ia l and 21 are bus ine s se s . The munic ipal water system wil l beextended throughout the impacted area; however, commercial fac i l i t i e s wi l lnot be given the opportunity to connect with the system.Comment f9EPA should conduct a detai led review of the removal of contaminants bvindividual ion exchange units . J

EPA Response to Comment #9Such a review was cons idered in the alternate water supply feas ib i l i tystudy and it was found to be costly and unre l i ab l e when comparedwith extend ing the c ity 's water l i nes .Comment HOWhy is the EPA propos i ng to use e ight inch water mains when a system ofthree inch ma i n s would meet the a r ea ' s needs at a s ign i f i cant cost s av i ng s?E p to Comment #10All p lans and spec i f i ca t i on s for extens ion of city water would beestabl i shed in accordance with the City of Odes sa Standards and Requ i re-ments for Street , Al l ey , Water , Sewer and Dra inage ImprovementsThese r egu l a t i on s bas i ca l ly set forth policy and min imum standards foracceptable mater i a l s and a minimum standard of workmansh ip for thecon s t ruc t i on of water mains that are to be connected to the City ofOdessa system. Further , to insure the integrity of the City of Odessasystem, s tr i c t compl iance with the city's plumbing code must be ma in ta i nedin al l connect ion and adherence to the regulat ion regarding crossconnect ions wil l be required. The city will assume all operat ion andmaintenance cost as soc ia ted with the system; therefore, the spec i f i ca t i on sfor the a l t e rnat ive must fo l low e i ther currently accepted city standardsor developed through successfu l negot iat ions with the City Counc i l .Comment til \Numerous people, wh i l e in favor of the extens ion on the mun i c ipa lwater supply, were concerned aboi-t the poss ib i l i ty of annexa t i on .EPA Response to Comment #11The City of Odessa mainta ins a policy of non service of water outs idethe corporate city l im i t s . As a part of th is study, the City Counc i lof the City of Odessa was requested to adopt a resolut ion ind icat ingwi l l i ngnes s to cons ider the spec ia l extens ion of city water Into the

8Odessa Chromium I and II s i tes to Improve the health, welfare, andsafety of cit izens in the areas contaminated with chromium, Thecity passed such a resolution on Ma~ch 25, 1986,In recent years , annexat ion by the City of Odessa has been on a voluntarybasis only. The construction of the distribution system makes the impactedarea no more or less subject to annexat ion .CommentWhat is the bas i s for the proposed chromium action leve l?

Q comment. |12The federally regulated Primary Drinking Water Standard for chromiumwas set at .05 pprn in 1 9 7 7 based on health effect s tud i e s . Thatrequirement is used as the ba s i s for the target concentrat ion .

1 V . Remain ing Pub l i c ConcernsThe residents strongly object to annexation by the City of Odessaand the subsequent encumbrance of city taxes and fees.