EPA Region 5 Records Ctr.

205284

ATTACHMENT 18

Superfund Record of Decision:Seymour, IN (Second O.U.)

(EPA/ROD/R05-87/050)September 1987

PB88-145131

Supecfund Record of Decision (EPA Region 5)Seymour Recycling Corporation SiteSeymour, Indiana (Second Remedial Action)September 1987

(U.S.) Environmental Protection AgencyWashington, DC

30 Sep 87

I

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4 ERA SuperfundRecord of Decision:

Seymour, IN (2nd O.U.)

INFORMATION SERVICESPRINGFIELD, VA. 22161 I

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1

TECHNICAL METOMT DATAfflttit mrf l.tOHtenoHt on rite rrxnt ttfon comfW* raw

EPA/ROD/R05-87/05UU. TITLi ANO BUST 1 Tlf

SUPERPUND RECORD OP DECISIONSeymour, INSecond Remedial Action - Final

T. AOTNORISl " '

~O.S. Environmental Protection Agency401 M Street, S.W.Washington, D.C. 20460

ms iTtTTITlittB. RBPORT OAT|

September 30, 1987B. MR'ORMiNO OROANI2ATION COOf

1 PBRFORMINa ORGANIZATION RCPONT NO

id. AROGRAM iLiMiNTsris: — • ———

13. TYM OF RIPORT ANO MRlOO COVf RIOFinal ROD ?.eport

1«. SPONSORING AOf f«CV COOB

800/00

I The Seymour Recycling Corporation (SRC) site, encompassing a fourteen-acre area, isapproximately two miles southwest of Seymour, Indiana. SRC and its corporatepredecessor, Seymour Manufacturing Company, processed, stored and incinerated chemical

I wastes at the site from about 1970 to early 1980. The facility was closed when SRCfailed to comply with a 1978 agreement with the State of Indiana to cease receivingwastes and to institute better waste management practices. In 1980, several thousand

f drums were removed from the site by two potentially responsible parties (PRPs). In' 1981, the O.S. EPA removed chemicals from tanks at the site and disposed of those wastesoffsite. A 1982 Consent Decree with potential PRPs resulted in the removal, between

cember 1982 and January 1984, of approximately 50,000 drums, 100 storage tanks and th( rirst foot of contaminated soil from about 75 percent of the site's surface. A Record

of Decision, signed in September 1986, evaluated the stabilization of the ground waterplume emanating from the site and selected the implementation of a plume stabilization

I system to extract, treat and discharge ground water to a waste water treatment plant.I Currently, the shallow aquifer under and just beyond the site boundaries, which servesapproximately 100 residences and businesses, is highly contaminated with more than 35different hazardous chemicals, including 1,2-dichloroethane, benzene, vinyl chloride am

1 1,1,1-trichloroethane.(See Attached Sheet}

IT. Kir WOMM AMD OOCUMINT ANALYSIS,*. oMcnirrom

' Record of DecisionSeymour, IN

1 Second Remedial Action - FinalContaminated Media: gw, soil, sedimentsKey contaminants: TCE, DCE, VOCs, benzene,

inorganics, organics1

B. DISTRIBUTION STATCMf NT

1

b.lOtNTIPIIMS/O*fN INOIO TiRMS

j

IB. S8CURITY CbAM iTtut HrfofttNone

20. SICUMITV CLAM iThit ftf,,

None

c. COSATi FMd/Crimp

31. NO. Of 'AOIff J

23.PHICI / ft?tz/m ±*sIf A f •»• 22N-t («•». 4-77) »*«vi«u* BOITIOM it

BPA/ROD/ROS-87/050, Seymour, IK

S«cond Remedial Action - Final

16. ABSTRACT (continued)

Th« selected remedial action for this second operable unit includes: deed and accessrestrictions and other institutional controls; implementation of a full scale soil vaporextraction system; ground water extraction and treatment by air stripping, mixed-mediacap; and excavation of 800 cubic yards of contaminated creek sediment and consolidationof the sediment beneath the cap. The estimated capital cost for this remedy is

,536,000 with present worth OfcM of $7,200,000.

ATTENTION

AS NOTED IN THE NTIS ANNOUNCEMENT,

PORTIONS OF THIS REPORT ARE NOT LEGIBLE

HOWEVER, IT IS TEE BEST REPRODUCTION

AVAILABLE FROM THE COPY SE2TT TO NTIS.

3

KECORD OF DECISIONALTERNATIVE SELECTION

SEYMOUR RECYCLING CORPORATION SUPERFUNO SITESEYMOUR, INDIANA

Statement of Basis and Purpose

This decision aocunent, with the attached Summary of Record of Decision(Incorporated herein as Attachment 1). represents the selected remedialaction for this site which was developed and selected in accordance wi tnCERCLA, as amended by SARA, and to the extent practicable, the NationalContingency Plan.

This decision concerning the appropriate remedial alternative forthe Seymour site is based primarily on the following document;:

1. Remedial Investigation, Volunes 1 and 2, Seynour RecyclingCorporation, Nay 12, 19>?6, prepared by C^M Hill, including theEndangerment Assessment, which is Chapter 9 of Volume 1.

2. Public Cement Feasibl1ity Study Report, Volumes 1 and 2,Seymour Recycling Corporation, August 29, 1986, preparedt>y CH2M Hi 11.

3. Community Relations Responsiveness Summary, Seymour RecyclingCorporation, September 1987, prepared by CH^M Hill.

4. The Comprehensive Environmental Response, Compensation, andLiability Act of 1980, 42 U.S.C. § 9601 et se£., as amendedby the Superfund Amendments and ReauthorTzation Act of 1986.

5. The National Oil and Hazardous Substances Pollution ContingencyPlan, 40 C.F.R. Part 300, November 20, 1985.

6. Correspondence from Or. C.W. Fetter, Jr., to David Favero, datedJuly 2, 1987.

7. Guidance on Remedial Investigations Under CERCLA, May 1985.

8. Guidance on Feasibility Studies Under CERCLA. April 1985.

9. Conceptual Level Design and Feasibility Study for In-situ AirStripping of Volatile Organic Contaminants from the UnsaturatedZone at the Seymour Recycling Corporation Hazardous Waste Site,Seymour, Indiana, Hydro Geo Chem, April 28, 1987.

10. Draft Conceptual Plan for Groundwater Remediation In the ShallowAquifer at the S*ymour Recycling Site, Geraghty & Miller,April 28, 1987.

11. Superfund Public Health Evaluation Manual, OSWE3 Directive42*5. 4-1 . Octooer 1986.

12. Memorandum from J. Winston Porter, Ass is tant Administrator, OSWE3,to Director, Waste Management Oivirion, Region V, and otners,entitled Interim Guidance on Superfund Selection of Remedy,December 24, 1*86.

13. Memor<jndum from J. Winston Porter, Assistant Administrator, OSUE3,to Director, Waste Management Division, Region v, and otners,entitled Additional Interim Guidance for FY '87 Records ofDecision, July 24, 1987.

14. Memorandum from J. Win;ton Porter, Assistant Administrator,to Regional Administrator, Region V and Director, Wastedivision Reyion V, and otneri, entitled Interim Guidance on Com-pliance with Applicable or Relevant and Appropriate Requirements,July 9, 1987.

15. Memorandum from J. Winston Porter, Assistant Administrator, OSWE-*to Regional Administrators, entitled Superfund Selection of Remedy,August 14, 1987.

16. Correspondence from Harry Join Watson III, Indiana Attorney General'sOffice, to Lawrence Kyte, dated August 8, 1986.

A substantial number of additional documents, which are included in the •administrative record, have also been considered in selecting the remedialaction for this site. An index to the administrative record is incorporatedas Attachment 2 to this document.

Description of the Selected Remedial Alternative

The selected remedial alternative represents the final remedy for the Seymoursite.

The selected remedial alternative includes the following major componentswhich are discussed in more detail in Attachment 1:

• Deed and access restrictions/other institutional controls toprevent future development of the site and adjacent propertyand to assure the integrity of the remedial action.

• Implementlon of a full scale soil vapor extraction systen.

• Extraction and treatment of contaminated ground water at andbeyond the site boundaries.

• Installation of a mlti-medla cap.

• Excavation of contaminated sediment and consolidation of thesediment beneath the cap.

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* A regular monitoring proyran to netermine the effectivenessof th» proposed remedial action.

Declaration

Consistent with the -Comprehensive Environmental Response, Compensationand Liability Act -of 1980 (CERCLA). as anended by the Superfund Anend.nents and Reauthorization Act of 1986 ( S A R A ) , and the National Oil andHazardous Substances Pollution Contingency Plan, 40 C.F.R. Part 300,I have determined that at the Scynour Recycling Corporation Site, tneselected remedial alternative provides adequate protection of hu.nanhealth and tne environment; satisfies trie preference for treatment thatreduces nobility, toxicity or volume to the naxinum extent practicable;and is cost-effective.

The State of lodiana has been involved with the development of the re-medial investigation/feasibility study. The State has been consultedon the selection of the remedy and is expected to concur.

The Office of Waste Programs Enforcement has concurred with the renedyselected for this site (Attachment 3).

I have determined that the action taken is consistent with Sectionof CERCLA, as mended by SARA, and is appropriate, balanced against theavailability of Trust Fund monies for ust at other sites.

Because hazardous substances will remain on-sUe, the 5-year reviewprovision of Section 121(c) of CERCLA, as amended by SARA, will applytt the Seymour site.

Valrtas V. Adamkui /\ TiateRegional Administrator

Attachments

ATTACHMENT 1

SUMMARY OF RECORD OF DECISION

Rt: ZUIAL ALTERNATIVE SELECTION

SEYMOUR RECYCLING L'JRPORATION

SEYMOUR, I NOiANA

September 25, 1987U.S. EPA. REGION VCHICAGO, ILLINOIS

Table of Contents

Section Page

Sue Location and description 1

Sue History 1

Results of the Remedial Investigation 3

Endangement Assessment 6

Technology Analysis Results 11

Groundwater Renedtation Technologies 11

Soil Remediation Technologies 16

Remedial Alternatives Development IB

Selected Alternative 22

Compliance With Other Environmental 28Requirements and Cleanup Standards

Groundwater 29

Potential ARARs 29

Other Standards or Criteria 32

Determination of Cleanup Standards 32

State ARARs 37

Discharge 37

Soil 41

Air 42

Radiation • 42

Enforcement Status 43

Community Relations 43

Future Actions and Schedule 44

ATSDR Comments 44

List of

Tables

Table 9.2from the Rt

Taole 9.7fron tne *l

Table 4.4from tne FS

Table 5.14fron tne FS

JWPE Hazard Criteria for SelectedCnenicals at tne SKC Site

Potential Exposure Pathways S3C Site

Su.-nary of Groimdwater ExtractionScheme Performance and Cost Analysis

Detailed Evaluation Sunnary Matrix

13

23-24

List of Figures

FiJure

Fiyure 1.2fron the FS

Figure 7.21fron the RI

Fiyure A.17from the FS

Figure 5.4fron tne.FS

Site Location/Study Area

Volat i le Organic Compounds 1n theShallow Aquifer, June, 1985

1989 Distribution of Vinyl ChlorideWithout Plune Stabilization AssuninyLowest Reported Retardation

Sedl'Tent Removal Areas 20

Appendices

Appendix 1 Projected Schedule for Future Actionsat the Seymour Recycling Superfund Site

Appendix 2 Community Relations Responslveness Sunnary

9

OF rf£:j<RD JF DECISIONRECYCLING CORPORATION

SITE LOCATION AND DESCRIPTION

The Seymour Recycl ing'Corporation site is "ocated 2.3 "tiles southwestof Cfie central Susirress district of Seynour, Indiana, near the nortnwestconwr of Freenan Municipal Airport and Industrial Park (Figure 1.2 fromthe FS). The sue covers about 14 acres, approximately 1/2 mile south ofthe Snyde Acres subdivision, lost of the area imnediately surroundingtne site is used far agriculture. A drainage ditch extends from the north-west corner of the site, (Northwest Creek), and drains into East-WestCreek about 10UU feet north of the site. The closest residence to thesit* is *rs. Ot te 's farm, just north of the creek. East-West Creex 'Tewsinto Von Fanye Ditch, which runs through the Snyde Acres Subdivision.

SITE HISTORY

Th« Seynour Recycling Corporation (SRC) and its corporate predecessor,Seymour Manufacturing Company, processed, stored and incinerated chericalwastes at tne si te from about 1970 to early 1980. The facility wasclosed when SRC failed to comply with a 1973 agreement with the Stateof Indiana to cease receiving wastes and to institute better waste nanaje-"wnt practices. In 1930, a state court placed the site under receiver-snip. Later tnat year, U.S. EPA fenced the site to restrict access andconstructed dikes to control runoff from the site. Several thousanddrums were removed from the site by two potentially responsible parties(WPs) 1n 1980. In 1931, U.S. EPA removed chemicals from tanks at thesite and disposed of those wastes at authorized disposal sites. In1982, the U.S. Governnent entered into a consent decree in U.S. DistrictCourt with sone companies believed to be PUPs. Under the agreenent, theP9Ps arranged for the removal of hazardous substances on the surface ofthe site.

The surface cleanup was conducted from December 1982 to January 1984 sya hazardous waste disposal firm. The cleanup was monitored by U.S. SPAami the State of Indiana. All wastes on the surface of the site, includingroughly 50,000 dnjns and 100 storage tanks, were removed and taken to author*ized disposal sites. In addition, the top foot of contaminated soil on thesite was removed from about 75 percent of the site and also transportedto authorized disposal sites. Clean fill was brought in to replacethe contaminated soil that was removed.

In 1982 and 1983, the U.S. Government entered into additional agreenentswith other PRPs. As a result of these agreements, a fund wa» establishedto b* used for future cleanup actions. For example, money from the P*Ptrust fund was used in 1985 to extend municipal water system pipelinesto the Snyde Acres area and noney from the trust fund will be used topay for a plume stabilization project at the site.

In August 1983, U.S. EPA began the remedial investigation (31) to deter-nirte the nature and extent of the potential long-term hazards that remain

10

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•£Efc'*N MU*< |Ci*L /A

StTE LOCATION/STUDY AREA

H ASHH.ITV STUDYtPA WA 70-SL31 0

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at and in the vicinity of the site. The HI also attanpted to identifypathways in the environment by which chemicals from the site may cone intocontact with people or the environment. Part of tne RI, the endanger.«ent assessment, estimates the potential impacts of the retainingcontaninants on human health and the environment if no further c'ean.uv actions are taken at the site. The RI, which was completed in May1966, serves as the prinary source of data U.S. £PA used in the Feasi-oility Study to develop alternative measures for reducing the potentiallong-tern threats posed by the site.

A phased feasibility study was completed in August 1986 that evaluatedthe stabilization of the groundwater contamination plune emanating frontne Seynour site. A Record of Decision was signed on September 30, 1436selecting the implementation of a plume stabilization project.

RESULTS OF THE REMEDIAL INVESTIGATION

GroundWater Contamination

Monitoring wells have been installed and used by various contractors tostudy the groundwater at and in the vicinity of the Seymour Recyclingsite. These studies indicate the presence of two aquifers: a shallowaquifer and a deep aquifer. The shallow aquifer, sometimes as snailowas six to eight feet below the surface, 1s separated from the deep aquiferby a silty clay aquitard that allows some water to flow fron the shallowto the deep aquifer.

Groundwater in the shallow aquifer flows to the north/northwest. faringwet periods, the high level of ground water 1n the shallow aquifer resultsin >, round water discharging into the East-West Creek. During drier periodsthe creek dries up and groundwater flows beneath the creek bed towardresidences 1n tne Snyde Acres subdivision. Downgradient of the East-WestCreek, a portion of the groundwater In the shallow aquifer discharges tothe Von Fange Ditch. The ditch occasionally dries up which Indicates ground-water flows beneath the ditch toward additional residences In the SnydeAcres Subdivision.

The deep aquifer, located from about 55 to 70 feet below the land surface,flows prlnaHly to the south. The area Immediately to the south of the sit*contains no wells or streams which could provide an exposure pathway forsite chemicals In the deep aquifer to contact human$ or wildlife. How.ever, there are wells located at Freeman Municipal Airport to the east ofthe site that currently draw fron the deep aquifer.

The shallow aquifer is highly contaminated with more than 35 different haz-artous organic chemicals, Including l,2-d1chloroethane, benzene, vinylchloride and 1,1.1-tMchloroethane. Most of the contaminants are directlyunder or just beyond the site boundaries. As of June 1985, the major por-tion of the contaminant plume extended 400 feet beyond the site boundary.(Figure .7.21 fron the RI) However, studies detected lower concentra-tions of organic chemicals as far as 1,100 feet downgradient of the siteboundary. The contaminants In the ground water are moving away from thesite at different rates; some as fast as 150 feet or more per year andOthers as slow as one foot or less per year.

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PIOUMI 7.21VOLATluE ORGANIC COMPOUNDS IN SHALLOW AQUIFERJUNE198S •••IIIIMI II••in

SIVMOUM NCCYCLINQ CORPORATIONREMCOIAL INVf STIGATION IPA WA 40 5 V01.1

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H*zarrtous organic chemicals have been detected in the deep aquifer.Concentrations range up to 1,344 ug/1 of total organic contaminants.The rate ana direction of contaminant -novement in the deep aquifer isnot well docmented nor understood.

Soil Contamination

Soil samples were collected during 1984 and H85 to determine theextent of contamination In the soil. Three types of locations weresampl ed :

1. Soil beneath the surface fron the groundwater monitoringsites (46 samples in 37 locations);

2. Sediments 1n the northwest drainage ditch next to the siceand In surface soils immediately surrounding the site (13Hsamples 1n 50 locations); and

3. Soil to a depth of six feet on the site (205 samples in illocations) .

Sanples from the 9 round water monitoring well locations and the nearsurface soils were analyzed 1n an on-s1te laboratory, with selectsamples being s«nt to the contract laboratory program (CLP) for acomplete analysis. Analyses of the soil samples indicate that soilsat various depths within the boundaries of the site are contaminatedwith hazardous organic and Inorganic chemicals. More than 54 organicchemicals were Identified in the soils, Including high concentrationsof 1,1,2-trichloroethane, carbon tetrachlorlde, 1,1,2,2-tetrachloroethaneand trlchloroethene. (RI, Vol. 1 Cnap. 6) (Record * ____ ) Inorganicchenlcals were found 1n the soils 1n concentrations greater than back-yround. (RI. Vol. 1. Chap. 6) (Kecord I ____ )

Contan1nat1on of near surface soils and sediments outside the site boun-daries 1s nuch nore limited. Sediment samples fron Northwest Creekshow the presence of low level concentrations of hazardous organic chemi-cal s. ( R T , vol. 1, Chap. 6) (RecoM * _____ )

Surface water and Wildlife Contamination

In 1983 and 1984, the U.S. F1sn and Wildlife Service (FUS) captured animalsand sampled soils and sediments 1n the area surrounding the Seynour Re-cycling Site. FUS collected additional sedlnent samples in 1995. Analysesof the animal tissues and the sediment samples Indicate that SOTO contami-nation from the site has migrated to surrounding land areas and waterways.

These studies Indicate that contaminants like those at the site have reachedEast-West Creek.

No surface water samples were collected during the RI. However, the presenceof contaminants In the sediment and animal tissue Indicate that the surfacewaters, at least on occasion, contain low levels of contamination. (RI, Vol .I, Chapter .s) (Record » ___ )

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ENDANGERMENT ASSESSMENT

The erdanyerment assessment ( £ A ) performed as part of the RIboth a public health and environmental evaluation. The public healtnevaluation portion of the EA was conducted in three major phases:1) tox icological evaluation, ?) exposure assessment and 3) r iskactenzation. A tsnef discussion of each phase fa l lows.

Toxicological Evaluation (RI, Vol 1, Chapter 9.2.1) (Record »

Over 70 cnenicals «<ere detected at. tie site. Table 9.2 from the RI pre-sents a sum-nary of the general toxicological categories into *nichselected chemicals fal l . Chemicals evaluated were selected based ontheir concentration, frequency of occurrence and potential toxic ef fects.

The toxicol'oyical properties are evaluated in quantitative tenns in theEA. Three types of quantitative evaluations are performed: 1) compari-son with avai lable and appropriate standards, criteria or guidelines,2) additive carcinogenic risk calculation and 3) comparison of estimatedpotential da t l y intakes of contaminants to acceptable intakes; The Health-Index. .

Exposure Assessment (RI, Vol . 1, Chapter 9.2.2) (Record * ____ ) k

The populations identified as actually or potentially exposed to chemicals"at or nitrating from the Seymour site are:

0 approximately 100 residences and businesses using groundwaterfrom the shallow

0 users of wells supplying the Freenan Municipal Airport and otherusers of the deep aquifer.

' populations downwind of the site; approximately 100 residenceswithin a 1 mile radius.

* people who may live on, work at or may otherwise use the site.0 people who would consume aquatic wildlife caught fron Northwest

Creek, Cast-West Creek, Von Fanye Oitch, and Heddy Run.

Exposure pathways are shown in Table 9.7 f-ron the RI-.

The routes of exposure vary depending on the migration pathway and thehuman activity. The potential routes of exposure are Ingestion, inhalationor denial absorption.

Risk Characterization (RI, Vol. 1, Chapter 9.2.*) (Record * _____ )

According to EPA policy, the target total individual carcinogenic risk re-sulting from exposures at a Superfund site may range anywhere from I < 10**to 1 x l(r7. (Superfund Public Health Evaluation Manual, October 1986).

Table 9.2am HJUMD cxznitiA FOX scuctxo omiiauj AT in ac site*

•oproaocuoa/*MtiiuvibugBs Acute Chronicx CareinooeaeitT* TerataqeBielty Htttaqeniexty Toxieijj

I I• X Z X I

X X X

X X XX XX X X X X

1.1-OicalerootftflM1.2-Olca4erootbeM X X X1,4-OXOxaae X XUod X XNotayleao eblorloe X X•atbyl pboaolMlcfcol X X X

l.i,2.2-t»tr»cftloroetbaae X X XX X

i,l,2-tne»leroetboae XXricfcUroetbaao XVlayl cUortoa X XXylaa* X

in* "CbaBical, IfeyelCBl, aatf Biological Propertlaa of Coaeoando fraaaat at•wU Site" Oeeie* oi MMW yrjgrMi teforcMiBC, (OHPt) U.S. X» INS. Crtt«zt«b»lo» u UM of OMPC. AB T* lAdicatM tto etaoleal M*CJ tb* erttcrta ««tlla«d by ONKfor tte porueiOAr toxle effect elMilf leatloo. Th« Uek of « T* uaote a elawifleatioa

aocMMTllr iaplr tbat tb« eAoaieal en act Jwro • toxic tf foct.*» eoipovDA 1» elanlflo* •• arnnntoiiic If It ia • kaom or »Mp«etod taa»a eardaogoa,if it b*» booa Bbom to oo euciaoonie »t • ?«rUouUr uto la aon Uua ono tpoeus or•ot la u aalMl bloomf , or If It has booa rbavn to umaaoa tbo laciaaafla of slto-opoeifie oollasaat tiavors la a tlaglo apoclvi or MI. and taora U a ttatltticallr itftu-I'jemt loat-raaponaa rolatioaattp la aoro tiiaa OM a»yuaa< m«v. (Ala cluaifleaUoela oot ".acaoaartlf tbo MM a* praoaau* br UK or CM la fablo 2-J).

aro el«Mlfl*« a* tacataaaoa aad roarodaetlvo toxia* if tboro la aooajaatlToof oa offaet la baaaaa or If at looot oao atae> IB vttelo aalaola la clearly poal*

Utrc. <h«9portotf la vitro e*14eaeo ta eaoaidorod aaffldoat to elaaaifr a eboaieal aa abasaro.

l la elaaalf la« aa •ataooaie if It baa «lw a poaltlv* nault la at leaat oaaof tbo aoaojtlla* la n«o or boetonal or aaoawllaa aell la ntro aaaara for amaaeolctty.

100 as/k<» aa

*CkaaUeala vlll bo eotaldorod to eanae eftroulc texldty If tboy eauao MTlooa lrr*»enlfeleeffects etbor tbaa eaacor or rvproducUv* effactJ after esrteodrl txpotvo to oral oaaoaof loaa tbaa 100 a$/ka/oa7« labaiatioo cooceatratioa* loaa tbaa too ao/a'f or Aanal ooaealoaa tbaa 100

vttl aw eoaaldaro4 to bo acutely toxic if it baa aa oral C0.B <i ICjg < ago BfVay, or a <anal LOJO < 400 at/k«. *°

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(Record 4 ) The 1 x 10'6 risk level is the point of departure for riskmanagement"! (1FS Guidance April 19«5) Record *______).

Further guidance 1ri regard to risk management is provided In the referencescited in the FS, che fS guidance document and the Sjperfund Public HealthEvaluation Manual.

Some .of the major risks associated with the sice Include:

• Qffsite miration — The off site migration of highly mobile organiccontaminants could result .in concentrations of contaminants at tnenearest offslte receptor locations (near Mrs. Otte's well, ap-proximately one-quarter nile northwest of the site) at concentrationsassociated with a 1 x 10~5 excess lifetime cancer risk In less thanfive years from 1384 (See Figure A.17 from the FS). One chemical,1,4-dioxane, could exceed the 10-day health advisory level at thenearest receptor in less than S years from 1984. Contaminants maymigrate and discharge to the Yon Fange Ditch, resulting 1n exposuresat that location, or may also migrate below the ditch to additionalresidences in the Snyde Acres Subdivision.

• use of Shallow Groundwater Onsite — Poiable use of the shallowgroundwater in a residential, commercial, or recreational settingcould result in adverse health effects. The contaminant concentra-tions onsite exceed current and proposed drinking water standards,criteria, ana guidelines. The major chemicals o' concern are thevolatile organic compounds (VOCs). Exposure to VOCs could result incarcinogenic health effects. For example, in a residential setting,estimates of dally contaminant Intake exceed acceptable levels, andestimates of excess lifetime cancer risk range from 1 x I0~l

to 2 x 10~1. This risk Is based on maximum reported concentrationsof all known potential carcinogenic VOCs.

' Exposure to Onsite Soils from Site Use— Site development could resultin exposure to contaminants In the soil. Ingestlon of soil couldresult in adverse health effects as measured by estimates of excesslifetime cancer risk (ranging fro* 3 x 10'3 to I x 10-*, depending onthe site use) and comparison of estimated dally contaminant intaketo acceptable Intake (acceptable Intakes for children could be exceeded).The major chemicals of concern in the sotl are VOCs.

• Environmental Concerns— Prior to the surface cleanup, releases ofcontaminants from the site resulted 1n fish kills. Sampling bythe U.S. F1sn and Wildlife Service 1n 1983 and 1984 detected con.tamlnants in aquatic and terrestrial organisms. Environmentalexposures are currently possible. Terrestrial organisms could comeonto tne site and be exposed to contaminants in r « soil. Re-leases of contaminants to the "East-West" creek are occuTlng, and

18

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SHALLOW AQUIFER

FrvtmtnMunicipalAirport

PIOURf A.1?1969 DISTRIBUTION OF VINYL CHLORIDE WITHOUT PLUMESTABILIZATIQN ASSUMING LOWEST REPORTED RETARDATIONftVMOU*MASHIUTY rruor|PA WA TfrllOI.0

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__ continued miration of contaminants (without remedial action) wi l lI eventually result in tneir release to the Von Fange Oitcn. This^ ' could expose aquatic organise to contaminants fron tne site.

.TECHNOLOGY ANALYSIS SUMMARY

The remedial action objectives established for the Seynour Site arediscussed 1n tne FS. Vol. 1, Chapter Z. (Record * _ _ _ _ )A large array of technologies were identified and initially screenedfor tneir ability to net: these objectives. Generally these technologiesaddressed tne two environmental nedla contaminated at the site:soil and grouodwater.

Groundwater Remediation Technologies

A. Shallow Aquifer

Technologies passing through the initial technology screening 1n theFS were combined into schenes to address the groundwater contamina-tion at and beyond the site boundary. These technologies includeextraction and injection wells, and slurry walls. Components forextracting groundwater, and then treating and discharging contami-nated groundwater as reconnended in the FS, are part of the overallgroundwater remedial action.

1. Groundwater Extraction Schemes (FS, Vol. 1, Chapter 4.1) (Record#_____)

There were three basic schemes that net the response objectivesand were evaluated 1n tne FS. Thes* schemes snould be reviewed asapproaches to groundwater extraction based on the currently avail-able information. They do not establish exact location, nurcerand punplng rates of a final extraction schene.

The schemes are:

1. extraction wells only,

2. extraction wells in combination with an injection wel l(s),and

3. extraction wells 1n combination with partial containmentin a slurry will around the site.

The approach in scheme 1 Is to extract groundwater at the down-gradient site boundary and at the downyradient extent of theoff-site contaminant plume.

Scheme 2 takes the approach of placing extraction wells on site,clustered around the nost highly contaminated area of the plume.These wells would naximlze inward radial flow from off-site; I.e.tne wells would draw groundwater from all directions toward thesite. An injection well would be necessary to eliminate an area

_ 20

-12-

of low Hydraulic gradient created by competition among the extrac-tion wells. A down gradient migration control well 1s also requiredIn this scheme.The approacn of Scheme 3 1s to use a slurry wall to contain contami-nants witnin the site bouidaries Out restore the aquifer outside theboundaries to the cleanup levels. A slurry wall would DC installeddown to the confining 1 jyer around the site to prevent continuedoff-site migration of contaminants. An extraction well would benecessary within the slurry wall in order to maintain the interiorwater table at an elevation below that of the exterior water table.Extraction wells would be necessary near the corners of the site toremove the contaminant plume outside of the slurry wall. A down-gradient migration control well Is also required in this scheme.

A plume stabilization project is currently in progress. Schemes Ithrough 3 were evaluated with a downgradient migration control extrac-tion well. The purpose of this well is similar to that of the plumestabilization well: to prevent further downgradient migration ofthe contaminant plume. The assumption used 1n evaluating the schemes1n the FS was that the downgradient migration control well would notbe Installed until 1989. One option was evaluated which assumed theplume stabilization well was to be Installed In the Spring of 1987.The results indicate the plume stabHzatlon well would decrease thetine of aquifer restoration by 1 to 3 years. (RI, Vol. 2, Appendix A)(Record # ___ ) This same Impact can reasonably be assumed to alsooccur with the other pumping schemes. Also, 1f the plume stabilizationwell is substituted for the downgradient extraction well 1t would notbe necessary to Install the downgradient migration control well asfar downgradient. (FS. Vol. 1, Chapter 4.1)

Computer modeling was used to compare the different schemes. The flowcomponent of the model was calibrated with historical data; however,the contaminant transport model was not calibrated. Calibration ofthe contaminant transport model was not possible because th«re 1snot an adequate history of contaminant concentration levels In thegroundwater. Verification of tne models was not possible because datawas not available with which the modeling predictions could be compared.Because of lack of calibration and verification, the model resultsshould only be used and considered accurate for relative comparisonsbetween schemes. In addition, in order to provide a basis for compar-ison. all schemes were assumed to begin extraction in Fall 1989. Resultsshould not be taken as absolute values.

Indicator compounds were selected on which to base the computermodeling. The selection criteria Included concentration, contaminantiroblHty, toxldty and trea* ability. (FS, Vol. 2, Appendices A and B)(Record * __ ) The nest mobile compounds determined the area that anextraction scheme would need to contain and the less mobile compoundsdetermined the time period a scheme must operate. Tetrachloroethenewas selected as the Indicator compound on which to oase performancecomparisons. Table 4.4 from the FS provides a summary of the ground-water extraction scheme performance and cost analysis.

*> 1<•» x

•13-

Taele 4.4

SUMMARY OF WOUNOWATER EXTKACTIM SCHEME PEXFCWMANCE AND COST ANALYSIS

Aquifer Restoration Time (Yrs!To Reach Cancer Risk Of:**

Extraction Scheme

1.

2.

Extractionwells only

Extraction-Injection

SoilOption Assumed

Source £1 iminatedNo Action

Source ElininatedNo Action

1 x 10-4

11-1750-80

9-lr>50-30

1 x lO-5

19-29>ioo

16-26>100

1 x 10-6

25-39>1W

21-33>100

Cost'

S1.417.JOO

51,643,000

3. Extraction-Containment

N/A U-22 20-30 27-41S3,085,000

* Total Present Worth Cost Over 30 years. Costs are for extraction only and 00not includ* treatment costs.

** T«troch1oro«chene used as indicator compound to determine punping times. Allpumping Mas assumed to start in Fall 1949.

90ft ~

2. Groundwater Treatment and Discharge

The following discharge alternatives for treated yroundwater from thesite were considered in the F$: 1) direct discharge to the NorthwestCreek, 2) aquifer reinjection, and 3} discharge to the Seynour PubliclyOwned Treatment Works (PUTU).

The POTW provides an added level of protection to the environment be-cause of the rid'ttional treatment of the treated groundwater prior toits discharge tg tne East Fork of the White River. Discharge to theSeymour POTW was carried forward 1n the PS for detailed evaluation ofranedial alternatives.

Discharge criteria for the Northwest Creek are not known because theynave not been identified by the Indiana Department of Environmental Maient (IiJEM) which is responsible for implementing the National PollutionDischarge Elinination System (NPDES). The criteria are expected to benore stringent than discharge criteria to the »OTW. State Water QuaHtyStandards adopted pursuant to 40 CFR Part 131 would be applicable tothis discharge. Treatment costs would increase as the discharge criteriabecome more stringent. The creek receiving treated groundwater dischargedfrom the site flows through the influence of the proposed extraction schene ;and would urovide recharye to the shallow aquifer. This recharge could in. =crease the volume of contaminated water that must be extracted and treated. *Further, the creek flows throuyh a residential area wnere, if the on-sitetreatment system were to fail, a threat to human health could result. There-fore tnis discharge alternative was not carried forward for further evaluation.

Treatment with reinjection was not carried forward because the aquifercould not accept the anticipated flow in any of the proposed extractionschemes. Therefore, an off site discharge would also be required usingreinjection. Operational problems such as clogging of the well screen,plugging of the formation or possibly having to excavate part of the multi-media cap for maintenance of the Injection well are expected with rein,jection. Those problems could reduce the effectiveness of any extractionscheme. To be compatible with the cleanup levels for the groundwater,reinjected water has to be at least as clean as the ultimate groundwatercleanup levels. This could cause Increased treatment cost relative todischarge to the POTW.

Tne treatment process developed for the extracted groundwater to be dis-charged to the POTW was designed to be able to achieve pretreatment standardstnat were preliminarily Identified by the City of Seymour .and the IDEM. TneCity of Seymour, under an authorized pretreatment program pursuant to 40 CFR4U3.5, has the authority to establish pretreatment regulations and criteria.The City consults with IDEM when Implementing the pretreatnent program.These preliminary pretreatment standards are subject to revision. The treat-ment process would most likely remain the same under the other two dischargealternatives. Refinements would be likely, however, due to more stringentdischarge criteria.

The treatment process consists of an air stripper followed by mixed mediafiltration, followed by carbon adsorption.

o o

-15-

The purpose of the air stripper is to remove strippable organic com-pounds which art present in tne groundwater in nigh concentrations.Vapor pnase carton treatment way be needed and Is included in tnecost analysis in this document. Air emission levels must be monitoreda.id a determination of tne public nealtn risk associated with tneemissions made. Evaluation of estimated emission levels indicates amaximum of a 3.6 x LU~° excess cancer risk level at 167 metersfro* tne site, fnis risk level means tnere could ce 3.6 additionalcases of cancer in a population of l.QUU.UUO if that population waslocated 167 meters from tne site for a 7u year period. Tn1s riskwas based on tne summation of 9 individual risks. (See memorandumfroa Steven Rotnblatt to Richard Bartelt. September 18, 19»6) (Record*_____). Based on actual population in the Seymour area, tneestimated emission levels would result in 2.7 x 10"3 (.0027) additionalcases of cancer within a SO km radius of the site In a 70 year period.

This risk is considered acceptable at this time for Initiation of theplume stabilization project without vapor phase carbon treatmentbecause: 1) the risk is within EPA's acceptable range of excess car-cinogenic risk, 2) the plume stabilization project is not expectedto pump the flow volume used In the risk assessment, 3) the qualityof the water being extracted by the plume stabilization well 1< ejectedto contain lower concentrations of carcinogenic compounds than was usedin the risk assessment, 4) the short period of operation prior toimplementation of the final extraction and treatment system, and 5)no exposure to humans because of institutional controls. Therefore,the plume stabilization project will be initiated but actual monitoringresults from the plume stabilization project treatabiUty studiesshould be evaluated when these results become available. Any combinedcancer risk greater than 1 x 10 caused oy air emissions must resultin treatment of the emissions. (See Memorandum from Steven Hotnolatt to«1chard Bartelt, September IB, 1986) (Record *___)

The mixed media filter will remove suspended solids and precipitatestnat form from oxidation of Iron from the groundwater in the airstripper.

The carbon adsorbers are necessary to remove less volatile organiccompounds. The low discharge criteria for phenol makes carbonadsorption a required part of the treatment system.

Estimated present worth for a 150 gpm treatment system 1s $6,115,000.

The treatment process may be altered when discharge criteria are estab-lished pursuant to the authorization procedure to discharge to the POTH.

8. Deep AquiferContamination in the deep aquifer has only consistently been detected1n monitoring well 222. The contamination levels detected within thesite boundary are above the cleanup standards, but contaminationabove cleanup standards has not been detected at or beyond the siteboundary. Therefore, remedial technologies specifically 1n relationto the deep aquifer were not evaluated in the FS. Required actionsare described in the section discussing the selected alternative.

24

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Soil Remediation Technologies

The soil ranediation technologies passing initial screening in the FSinclude:

1. capping,2. soil removal/on site disposal ,3. soil removal/off site disposal ,4. onsite incineration,5. in-sltu soil washing, and6. in-situ vapor extraction.

These technologies were evaluated separately from tne groundwatertechnologies, hut there is an important linkage >)<»t*een the tineof restoring the shallow aquifer and tne soil contamination. Thesoil serves as the source of contamination to the shallow aquiferwnicn in turn 1s the source of contanination to the deep aquifer.The source of contamination to the shallow aquifer ^ust be eliminatedto allow tne snallow aquifer to be restored and to prevent additionalcontanination of the deep aquifer.

1. Capping

upon the initial screening of technologies, the capping optionmerited further evaluation as a renedlal action or a component of amore comprehensive renedlal action. The preliminary design of thecop used in cost analysis had a 3% slope, and successive layers of atwo foot vegetative cover, a geotextile layer, a synthetic drainagelayer, an 80 nil synthetic line'', and 2 feet of compacted clay. (SeeFS, vol. I, Chapter 4,3.1) (Record * ___ ) The design is consistentwith RCRA closure requirements set forth at 40 CFR Part 264, SubpartG. The cap 1s estimated to take 2 construction seasons to install.

Estimated present worth 1s 55,794,000.

2. Soil Removal /Off site Disposal

The soil removal option analysis was based on a cleanuo level thatrepresents a 1 x 10'6 excess lifeline cancer risk for residential use.This risk Is within the acceptable range under current EPA guidance.These levels also should provide adequate protection to the ground water.The volume of soil 1s estimated at 95,800 cubic yards or 7,900 truck-loads. Disposal 1s assumed to take place within a 250 nile radius ofthe site over a period of .5 to three years.

Estimated present worth Is $40.805.000.

3. Soil Removal /On site Dis,x>sa1

Removal of soil and disposal in an onsite RCRA compliant landfill wasevaluated In the FS. As in the above option, 95,800 cubic yards ofsoil would be renoved. The size of the RCRA compliant landfill wouldbe approximately 4.5 acres in area and 40 f€et high at Its center,

- L 7 -

Heplacenent coses for cap components are Included for cost analysispurposes. Construction of the landfill Mould take at least two Outpossibly three construction seasons to complete.

Estimated present worth is $9,229,000.

4. 0*>-slte Incineration

Rotary kiln was proposed in the FS as the nost effective and appropriateincineration technology and was used for cost estimation purposes.Six and a half years were estimated to be needed to themally treat theestimated volune of contaminated soils and other waste.

This option Is considerably more complex to Implement and operate thanother soil technologies. There Is limited experience with the processneeded to demonstrate compliance with the technical requirements foronsite, temporary Incinerators and -"taking this fianonstration couldtake a considerable amount of time. Operation of an incinerator is alsovery labor Intensive and requires skilled operators. The FS assumedit would take at le*.t 5.5 years to complete incineration. The solidresiduals from the incineration process would need to be demonstratedto not pos* a threat to public health, welfare and the environment.For the purposes of the FS It was assuned the solid residuals wouldbe hazardous and must ie disposed of in an onsite RCRA compliantlandfill.

Estimated present worth is 528,833,000.

5. In-s1tu Soil Washing

The FS stated that this technology 1s attractive because it removes themore soluble contanlnants fron the soil 5y accelerating their leaching intothe groundwater and then collecting the contaminated groundwater. To in-pi ement this technology at the Seynour site, surface soil that was placedover the site after the 1982 surface cleanup would have to be renoved.The relatively lower pemeablllty of this surface cover material would in.hiblt infiltration of water applied to the soil.

A pilot-study would possibly have to be performed on a portion of tne siteto develop operational and effectiveness information. It is estimatedit will take 3-6 years to maximize the effectiveness of the soil washingprocess. All contaminants would not leach fran.the soil,.so some contani-nants would remain In the soil and a cap would be needed.

Estimated present worth Is S8.67S.OOO.

6. In-$1tu Vapor Extraction

In-situ soil vapor extraction takes advantage of the volatile nature ofsome of the contaminants to remove then fron the unsaturated zone.Vertical extraction wells were used in cost estimates. However, in areaswhere Che water table 1s high, horizontal extraction pipes may be more

effectlve. (See FS, Vol. 1, page 4-97 and Hydro Geo Chen Report, Apri l m1987) (Record *___ and Record *___)

A cap must be Installed on-site in conjunction with any soil vaporextraction system to prevent leacnihy of contaminants to the groundwater,to prevent direct contact with contaminated soil and to prevent run-offof contaminated water or sediment.

Estimated present worth is 59,554,000.

REMEDIAL ALTERNATIVES DEVELOPMENT

The technologies that passed through the Initial screening in the FSwere then developed and evaluated, according to the criteria in the NCP,In Chapter 4 of the FS. (Record »__) The technologies were then com-bined in the FS into a number of remedial alternatives to address allthe public health and environmental risks posed by the Seymour site.The NCP requires thbc alternatives be developed and evaluated for tnefollowing categories:

0 No action.0 An alternative for treatment or disposal at an off-site

facility approved by U.S. £t>A.0 An alternative which does not attain applicable or relevant

public health and environments! standards but will red-jcethe likelihood of present or future threat from hazardoussubstances and provides significant protection topublic health, welfare and the environment.

0 An alternative which attains all applicable and relevantfederal public health and environmental requirements.

• An alternative which exceeds applicable and relevant federalpublic health and environmental requirements as currentlyknown.

The alternatives developed 1n the FS were also developed wir.n the Intentof nteetlng applicable or relevant and appropriate State requlrenents.These requirements are Identified in a correspondence from Harry JohnWatson III, to Lawrence I «t«, August 8, 1986. (Record *_______)

In addition, alternatives were Included 1n the FS that addressed thecleanup standards require by Section 121 of SARA. The NCP requiredthat EPA develop these t-ues of alternatives before the passage ofSARA, and 1t was EPA's pjlicy to do so. (See 40 CFR Section 300.68}(n))

Alternatives developed Included treatment alternatives that minimized thepublic health and environmental risks associated with long tern manage-

•

-19-

i*nt of residuals and alternatives Involving treatment as a principalelement that permanently and significantly reduces the toxidty, (mobility,or volune of hazardous substances at the site. Containment options werealso evaluated In the FS.

Connion Features

alternatives analyzed in tne FS, except the no action alternative,included a number of coanon features that are necessary to supplementthe majo«- soil a.id groundwater components. These comon featuresare:

9 The- existing onsite buildings would be denolished and disposedof in accordance with the alternative selected. The volumeof building rubble is estimated at 2,200 cubic yards. Thelust be razed In order to allow for the Installation of thecap, soil removal or the Implementation of vapor extractionor soil wasning.

0 Deed ana access restrictions ancl/or other Institutional con-trols would be placed on the SRC site property and the areasurrounding the site. Deed restrictions would prohibitexcavation of soil, building construction on site and groundwater extraction. Off site ground water withdrawal restrictionswould be necessary to prevent any adverse Impacts to theproposed extraction well system. These would deal primarilywith prohibition of tft» Installation of large volune wells onneighboring lands that could negatively Impact tte recoverypatterns of the extraction well systen. Use of the adjacentland owned by the City of Seymour would have to be limitedin order to prevent a public health threat during operation ofthe vapor extraction system. Access to the site would be con-trolled by fencing, and the fence would be posted with warningsigns. The timing of the restrictions may vary depending onthe alternative and when cleanup standards are achieved, liltprecise location, magnitude, and timing of the restrictionswould be determined -during the design phase of the remedialaction.

• Contamlr r.* migration would be assessed through a regular groundwater and surface water monitoring program. Monitoring isnecessary to determine the effectiveness, of any remedial action.

* On* foot of sediment would be removed fron the Northwest Creekand from the ditch just north of the site as shown on FigureS.4. The approximate volune of sediment to be removed wouldbe 800 cubic yards. The sediments would be addressed withthe same technologies as the soils for the various alternatives.The sediments pose a potential threat to aquatic life in theditch and creek.

28

1ri

iiii

i FIQUME 5.4SEDIMENT REMOVAL AREASSEYMOUR RICYCUNG CORPORATIONMASItlUTY STUDYIPA WA 70-SLQ1 0

• Temporary runon and runoff controls would be constructed at t«e, site as needed. These controls wouM prevent any off-site nitrav ... of contaminants ty surface water duriny construction activities on

tne site.

EM, in Chapter 6 of tne FS, added tne following feature to be includedin all remedial alternatives.

• Residential wells In tne Snyde Acres subdivision would b« properlyabandoned if consent is obtained fron tneir owners.

•

This feature 1s desirable to elininate potential conduits for contanina-tlon to enter the shallow aquifer fron residential wells which are nolonyer beinj used. Under a previous response action, the residences r.avebeen hooked up to the City of Seynwur's water supply distribution system.

The Assembled Alternatives

Th« assenbled alternatives, except the no-action alternative, Include tnecownon features described above and specific soil and uroundwater com-ponents.

Tn« assembled alternatives are:

I. No action.?, Offsite soil disposal/Groundwater extraction and treatment.1« Onsite soil disposal/Groundwater extraction and treatment.4. Onsite soil Incineration/Groundwater extraction and treatment.5. Multi-nedla cap/3roundwater extraction and treatment.6. In-situ soil washing, multl-nedla cap/Groundwater extraction

and treatment.7. Vapor extraction, multf-nedla cap/Groundwater extraction and

treatnent.

An alternative was considered for each category required by the NCP.(See FS, Vol. 1, Figure 5.2) (Record * ___) Tht detemlnationsIn the FS as to attainment, exceedance or non-attainment of applicableand relevant public health and environmental standards was madeprior to SARA beln^ enacted.

The total capital cost, total operation and nalntenance cost and totalpresent worth are presented beiow for eacn alternative. •

Alternative Total Capital Cost Total 0AM Cost Total Present Worth*

1 0 0 02 $44,976,000 $4,659,000 $49,635,0003 12,275,900 5,235,000 17,510,0004 28,281.000 3.700,000 36,981,0005 9,034,000 4,929,000 13,963,0006 11,845,000 5,614,000 17,459,000

. 7 10,636,000 7,200,000 I7,736,v;00

30

*Present worth is based on a 10 percent interest rate and a 30 year O&Mperiod. ^ \

In accordance wltn the SCP, a detailed analysis of the assembled alter,natives was performed. The factors evaluated we^e technical considera-tions, public health,'welfare anct envlromental impacts, institutionalconcerns and cost.

A sunmary of the detailed evaluation of alternatives is presented inTable 5.14 from the FS.

SELECTED ALTERNATIVE

The alternative reconoended by EPA in the FS was a modification of numoer7: Soil vapor extraction and nultimedia cap/Groundwater extraction andtreatment. This.alternative, with ninor modifications discussed below,is tne selected renedy fc»r the site. j

The criteria for selecting this remedy are contained in the NCR at 40 CFR \Part 30U.6a(j) and Sectio^ 121 of the Superfund Amendments and R*author1-zation Act of 1986, Public Law 99-499, 100 Stat. 1613 (1986) or "SARA".In addition, a Hecenber 24, 1986 memorandum titled "Interim Guidance on :Superfund Selection of Remedy" from J. Wlnston Porter, Assistant Admini- „strator to Regional Adrinistrators and other regional management wastaken Into consideration in selecting an alternative. .

The vapor extraction system selected for implementation at the Seynour isite would renove a substantial amount ot the estimated 200,000 pounds •of volatile organic compounds (VOCs) that are present in the soil in highconcentrations. The VOCs are generally th* rcost mobile and toxic com.pounds present at the site. The endangernent assessment identified thisgroup of compounds as posing tne greatest threat to human health viagroundwater ingest ion since the majority of these compounds are carcino-gens and are present in high concentrations. (RI, Vol. I, Page 9-73)^Record #___) The non-volatile organic compounds would remain in thesoil. However, these compound; are relatively Immobile and may ulodegradeover time. The application of soil nutrients In order to stimulate bio-degradation 1s included In the selected alternative. This alternativeutilizes treatment technologies and reduces the mobility, toxidty andvolume of hazardous substances at the Seymour site to the maximum extentpracticable.

A detailed pilot study was envisioned 1n EPA's recommended alternativein the FS. However, based on reports submitted by the defendants inthis case (see Hydro Geo Chem Report and Geraghty and Miller Report,both dated April 28, 1987) (Record * ____and » _____), It Isreasonable to gather additional site data needed to design a soilvapor extraction system, apply nutrients to stimulate biodegradatlon,Install the soil vapor extraction system, and then construct themulti-media cap. This phasing of Implementation of tne system minimizestne additional time the contaminated soils are exposed to the environmentand 1s therefore preferable to the pilot study proposed In the FS. ( )

0 1o J.

11 Mini:-(I 1 i&lli i

(V

it

liU

Iiiii111

i!

!ill

I"I!**

li*l ft*t*i-8-l ^fin i«!!hij{«iiil iiiriihl

I' ilfiil-'ll .HI ijiji H*I

••> M! at'! llsl5 -1-**.{iSlll li Hi, }!Hn iiili )iii i'dul ill!h

1154

15 li !1

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I piiij!• i » • • • * —f « * « S I « •— • • *!r»= f^*5 *: .**jssS-? I r?f^ jj i||»M

l

i

! I'Ir:

ilii1

-es-

The mvlti-media cap Mould provide protection from direct contact withthe rewininy contaminants and substantially reduce the threat of long-term nitration of remaining non-strippable contaninants into the en.v1ronment.

The groundwater extraction component of the selected remedial actionis scheme 1. Scheme 1 Includes dOMftgradlent extraction wells at thesite- boundary tn combination with the plume stabilization well. Thegoal Is to meet the cleanup levels listed in a later section of thisdocument and to prevent uncontaminated portions of tne shallow aquiferfroa being contaminated above these cleanup levels.

This scheme is nearly as effective In restoring the aquifer to cleanuplevels as scheme 2, which was recommended in the FS. According to model-ing projections,'schene 2 1s advantageous because it will restore theaquifer quickly end maintain a hydraulic gradient from the deep aquifertoward the shallow aquifer. However, scheme 2 adds an additional level ofoperational and maintenance difficulty because of the Injection well.If the integrity of the cap 1s compromised for maintenance of the Injec-tion well Included 1n scheme 2, additional leaching of contaminants fromtne soil to the groundweter could take place. Additional leaching wouldprolong groundwater quality restoration. Scheme 1 also costs less thanscheme 2. The simplicity In operation and maintenance of schene 1 makestt tha> selected ground water extraction component. (See Fetter corres-u0nce*ca. July 2, 1987 and Gerayhty A Miller Report, April 28, 1937)(Recant »___and Record f__p)

Sch«e 1 costs considerably more than the other two schenes and is <nuchless reliable because of the difficulty of Installing the slurry wall an<jthe potential failure of the slurry wall.

For the deep aquifer, additional ev-aluatlon, and extraction and treatmentif necessary, are required as part of the selected remedy. The wellsshould be of adequate design, number and location to allow for rapiddetection o_f contaminants migrating off-site and to enable extractionof contaminated ground water 1f necessary. Part of this evaluationshould include a time-series analysis of water quality from monitoringwell 222. This will aid in determining the consistency of the contam-ination and possibly the extent of contamination near this monitoringwell. Extraction of contaminated groundwater for treatment and dis-charge should occur if contaminant concentrations above the cleanuplevels arc detected at vr beyond the site boundary. Treatment anddischarge can bt performed in the same manner as 9roundwater extractedfrom the shallow aquifer. The treatment system for the shallowaquifer must be sized or provisions made for upgrading the system forthe potential flow from the deep aquifer. In addition to Immediatepumping of the deep aquifer. If concentrations exceeding the cleanupstandards are detected, a plan for further investigation or additionalremedial action must be prepared.

The groundwater treatment and discharge components of the selected remedyare air stripping, mixed-media filtration and carbon adsorption with thetreated water being discharged to the sewer system leading to the Seymour

34

-26-

PUTW. The treatment components can be modified to most efficiently meetdischarge criteria ultimately to be set by the POTW. (See discussion onpages 37-4U) The discharge criteria will be established to irevent upsetof the POTU, pass through of contaminants to the East Fork of the WhiteRiver and interference or accumulation in the POTH's sludge.

In addition to the soil and groundwater operable units, the selectedremedy also includes the features common to all alternatives, exceptno action. These features are discussed or. page 19 above.

Alternative 1, no action, is not acceptable for the Seymour site becauseof the existing and potential threats to human health and the environ-ment. These risks were summarized earlier in this document.

Alternative 4, which Includes Incineration, ha*> the distinct advantagethat if operated properly, it would destroy the organic hazardous sub-stances present In the soil. For certain waste types, this technologymay be appropriate, but at the Seymour site, the volatile organlcs posethe main threat to human health and the environment, and vapor extractionis a less costly and mechanically simpler system for removing VUCs.In addition, mere are safety and environmental risks associated withincineration technology. Other disadvantages associated with Incinera-tion are the potential lony time needed to obtain approval to operate,the disposal of ash and the total system cost. The ash must behandled as a hazardous waste unless 1t can be demonstrated 1t 1s nota threat to human health and the environment. The cost for theincineration alternative 1s more than twice the cost for the selectedvapor extraction alternative. The estimated cost of Incineratingsoil has a high degree of uncertainty based on the limited amount ofexperience with Incineration of soils. On balance, it 1s EPA'sjudgment that for this site, the benefits that can be realized fromthe vapor extraction alternative are superior to the Incinerationalternative due to the complexity of Implementation, the safety andenvironmental risks, and the high cost of Incineration in relation toother effective alternatives.

Alternative 6, 1n-s1tu soil washing, has nany of the same advantages asvapor extraction, such as enhancing natural processes to reduce the con-taminant concentration, and minimizing excavation. From the human healthand environmental perspective, however, 1n-s1tu soil washing creates thepotential for relatively less mobile contaminants to be flushed into theaquifer that, under natural conditions, would take many- years to migrateto the groundwater or would never reach the aquifer If the site was cap-ped. Once the contaminants reach the shallow aquifer, the groundwaterextraction system may not capture these relatively immobile compounds be-cause of their slow migration rates; thus, the potential remains for long-term public health and environmental risks from groundwater contamination.This risk 1s unnecessary since the vapor extraction system would removethe VUCs, which art of primary concern, by extracting them from the sur-face and a cap would be Installed to prevent additional leaching of con-taminants to the shallow aquifer. In addition, In order for soil washingto be Implemented at the Seymour site, the upper one foot of soil wouldneed to be removed, or otherwise altered to Increase its permeability.This soil cover was placed on the site's surface after the surface clean-

»• tX J

35

up was perfomed in 1983. It has a low enough pemeability to limit in-filtration into the highly contaninated soi ls, thereby reducing theeffectiveness of the washing process. As proposed in tne PS study, thissoil would be placed in a RCRA-type landfill in tne triangular area intne northeast pert of the site. The need for soil excavation also causessoil washing to be less suitable and desirable for implementation at theSeymour site compared to vapor extraction. Tne cost of this alternativeis comparable to that of vapor extraction.

Alternative 2, which includes offsite soil disposal at an EPA-approvedfacility, is not selected for several reasons. Primarily, SARA makesoff site disposal the least preferred remedial technology. (SARA, SectionI21(b)( l)} Off site disposal may not be able to be completed prior to tneeffective date of the RCRA land disposal restrictions for CERCLA wastes;therefore treatment of the soil would be '^uired, adding to tne cost ofthis alternative. (RCRA, Section 3004(d) and ( e ) ) Excavation of the soilwould create uncontrolled releases of volati le oryanics into the air aswell as the potential for promoting the flushing of contaninantsinto the groundwater during rainfall. Excavation also poses a riskto the construction workers on site by increasing the potential forthen to come in contact with tne contaninants. The selected vaporextraction alternative requires ninimal a :urbance of the soilsince it is an in-situ technology. Transpc nation of the contaninatedsoil increases the risk to hunan health, we1 fare, »' •« environmentfrom accidents and spills along public roadways. ... . .*w of thefact that landfills are subject to leakage, long-term negative humanhealth and emrironncntal impacts could occur at the facility where thewastes are disposed of. Moreover, the present worth for this alternativeis more than three tines the cost for the selected in-situ soil vapor •extraction alternative.

Alternative 3, which Includes on site landfill Ing of the contaninatedsoil, has nany of the sane potential negative aspects as offsite land.filling mentioned in the previous paragraph. Although the risksassociated with transportation would not apply, all the wastes wouldr ana in onsite. The waste volume, toxicity, and mobility would be thesat*. Since the wastes are not treated, they could create a long-ternproblem should the onsite landfill leak. The estimated cost forAlternative 3 is about the sane as for the selected alternative, butEPA oelleves it would represent greater risks to human health/welfareand the environment and does not satisfy the statutory preference In SARAfor permanent solutions and treatment to the naximum extent practical.(SARA, Section 121(b)(l) Therefore alternative 3 Is not .cost effective;nor does 1t protect public human and the environment to the same degreeas the selected alternative. As in alternative 2 above, RCRA landfillrestrictions may be 1n effect prior to completion of this remedial action.Therefore, treatment sucn as Incineration would he necessary prior *o dis-posal, Increasing the cost of this alternative. TMs would make thisalternative equivalent to alternative 4, which has already been discussed.

Alternative 5, which includes a multi-media cap and 3 round water extractionand treatment, 1s not selected since EPA believes if the cap fails, there

36 I

1is a significant of additional leacning of cootaninants intosallow aquifer oecause the soils are not treated. The statutorypreference for treatnent which oermanently and significantly reducesthe volume, toxlcity or mobility of Hazardous substances is notsatisfied. This causes alternative 5 to oe not as protective ofhuman health and the e.nv 1 roment as the selected alternative. (See FS,Vol. 1, pp.5-10 and'll) (Record * ) The selected alternativeincludes instal lation of a multimedia cap, but only in combinationwith in-situ soil vapor extraction. It is believed that the vaporextraction component should greatly reduce the concentration of VOCs,the roost mobile and toxic chenicals at the site, in the unsaturatedsoils.

The cost of the selected alternative is higher than the cost of alter,native 5; however, EPA believes that the greater treatment and subse-quent human nealtn and environmental protection offered by the selectedalternative outweighs the additional costs.

COMPLIANCE WITH OTHER ENVIRONMENTAL REQUIREMENTS AND CLEANUP STANDARDS

This section identifies the requirements of the environmental laws, regula-tions and policies that are applicable or relevant and appropriate standards(ARARs) for the selected alternative for the Seymour site. •

t»

Cleanup standards must insure that the remedy is protective of human healthand the environment. (See SARA Section 121(d)(i))

Applicable requirements are cleanup standards, standards of control, andother substantive environmental protection requirements, criteria orlimitations promulgated under Federal or State law that specificallyaddress a hazardous substance, pollutant, contaminant, remedial action,location or other circumstance at a site. A requirement Is "applicable"if the remedial action or circumstances at the site satisfy all of thejurisdictional prerequisites of the requirement.

Relevant and appropriate requirements are cleanup standards, standardsof control, and other environmental protection requirements, criteria orlimitations promulgated under Federal or State law that, while not legally"applicable" to a hazardous substance, pollutant, contaminant, remedialaction, location or other circumstance at a site, address problems or :situations sufficiently similar to those encountered at the site that jtheir us* 1s well suited to that site. \

i. I

"A requirement that Is judged to be relevant and appropriate must be \compiled with to the same degree as if It were applicable. However, ithere 1s more discretion 1n this determination: it is possible for onlypart of a requirement to be considered relevant and appropriate, therest being dismissed if judged not to be relevant and aporoprlate in agiven case." (Interim Guidance on Compliance with Applicable or Relevantand Appropriate Requirements, p. 3, from J. Wlnston Porter,dated July 9, 1987) (Record *___)

While non-promulgated advisories or guidance documents Issued by Federalor State governments do not nave the status of potential ARARs, they'tay be considered 1n determining the necessary level of cleanup for pro.tection of human health and the environment. (See Interim Guidance onCompliance with Applicable or Relevant and Appropriate Requirements, fronJ. Wlnston Portttr, dated July 9, 1937).

GROUNDWATER

Four groups of federal standards and criteria and other health-basedlevels were considered In detemlning the ARARs for the groundwatercleanup standards for the remedial action at the Seymour Site.

HCLG - Maximum Contaminant Level Goals established under the Safe Drink,ing water Act. HCLGs are nonenforceable health goals, set at levelswhere no known or anticipated adverse health effects will occur 1n ex.posed people, and which allow for a margin of safety.

MCL - Maximum Contaninant Levels established under the Safe Drinkingwater Act. These are the maximum contaninant concentrations allowedIn regulated public water supplies. Levels are based on a chemical'stoxiclty, treatability (Including cost consideration), and analytical1imits of detection.

rtCRA Groundwater Protection Standards • RCRA Groundwater ProtectionStandards established under 40 CFR Section 254.94 Include BackgroundConcentrations, Maximum Concentration Limits, and Alternate Concentra-tion Limits (ACLs). These standards are specified in permits Issuedto hazardous waste management facilities pursuant to RCRA.

WQC - Ambient water Quality Criteria for Hunan Health established underthe Clean Water Act. The original WOC assumed that people drank con-taninated surface water and ate contaminated fish that lived in chatwater. The Superfund program has adapted these criteria to groundwaterby calculating the corresponding contaninant concentration forexposure to contaminated drinking water alone. (Superfund PublicHealth Evaluation Manual, October 1986) (Record i_____)

Potential ARARS

A. Safe Drinking Water Act—HCLGs and MCLs apply at the tap to "publicwater systems," which are water systems havi-ng at least 15 serviceconnections or regularly serving at least 25 Individuals. (42U.S.C. section 300(f)(4)) A public water system has not beencontaminated by the Seymour site; therefore, SDWA standardsare not "applicable" to the site. Whether these standards are"relevant and appropriate" to the site is discussed below.

1. MCLGs—SectTon 121(d)(2) of SARA mandates that remedial actionsrequire a level or standard of control that attains MCLGs1f they are relevant and appropriate under the circum-stances at a site. As cleanup goals, MCLfis may be rele-

38

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vant to remedial actions at Superfund sites where thegroundwater at the site Is or nay be used for drinkingwater. Although most area residences are connected toth» Seymour municipal water system, the aquifers at theSeymour, site are used for drinking water. (See RI, Vol. 1,p»j. 9r21) (Record * • ) MCLGs may therefore be"relevant" to the remedial action at the site; however,tney are not "appropriate," E?A's "Interim Guidanceon Compliance with Applicable or Relevant and AppropriateRequirements" states on. page 9 that MCLs are generallythe relevant and appropriate cleanup standard for ground-watei* that may be used for drinking. (Record *______)(MCLs are discussed below), unlike MCLs, HCLGs arebased entirely on health considerations and do not takecost or feasibility into account. As health goals,HCLGs are set at levels where no known or anticipatedhealth effects ">ay occur. Including an adequate marginof safety. MCLs ar« required to be set as close asfeasible to their respective HCLGs and are set at thesame levels as MCLGs for noncarcinogens. MCLs are thestandards for public water supplies. ERA has thereforedetermined that MCLs, rather that HCLGs, are relevantand appropriate as cleanup standards for groundwaterthat may be used for drinking water, such as the aquifersat the Seymour site. (See also correspondence dated May21, 1967 from Lee M. Thomas to the Honorable James J.T.orlo) (Record i_______)

2. MCLs - MCLs are "relevant" to the remedial action at theSeymour site because the aquifers are or may be used fordrinking water. MCLs are "appropriate" because they setenforceable drinking water standards for public watersupplies. (See July 9, 1987 "Interim Guidance on Compli-ance With Applicable or Relevant and Appropriate Require-ments" and the May 21. 1987 Lee M. Thomas letter to theHonorable James J. Florlo) (Record t and» ) As MCLs apply to water at its point of dlstrl-bution ("at the tap"), these levels are appropriate forgroundwater at this site because residential wells thatwould use the aquifers generally have minimal or notreatment. Thus, these standards Mill have to be appliedIn the groundwater Itself to ensure safe levels at thetip.

Resource Conservation and Recovery Act (3C3A) - The RCRA regulationsapplicable to facilities treating, stormy or disposing of hazardouswaste became effective November 19. 1980. (See 40 CFR sections264.1 and 265.1). The Seymour facility ceased operating andaccepting wastes prior to Chat date. These regulations aretherefore not legally "applicable" to the Seynour facility forthe groundwater cleanup. Whether RCRA regulations ars "relevantand appropriate" to this site 1s discussed below.

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1. Listed Maxinun Concentration Limits - The groundwatertection standards at 40 CF« Section 264.94(aK2) listmaxima* concentration limits for fourteen compounds. Therearc listed levels for three contaminants of concern at theSejwour site. The levels listed at 40 CFR 264.94(a)(2)art SO U4j/l for lead, 10 ug/1 tor cadmium, and 1,000 ug/1for oari'un. These levels are based on the Safe DrinkingHater Act MCL, which is set at a level protective ofhunan health and the environment. These levels aretherefore "relevant and appropriate" for the ground watercleanup at the site.

2. Alternate Concentration Limits (ACLs) - EPA may estab-Tish ACLs In lieu of background levels or listed naxinuncontaninant levels if the ACL "will not pose a substan-tial present or potential hazard to hunan health or theenviroment as long as the [ACL] is not exceeded." 4oCFR § c64.94(o). Section I21(d)(2)(8)( i i ) of CERCLArestricts the use of ACLS as cleanup standards for on-sitecleanups that assume a point of human exposure beyondtnt facility's boundaries. The selected remedy for theSeymour site does not assume a point of human exposureto contaminants exceeding ACLs beyond the facility boundary:the cleanup standards are required to be met at the boundary.Therefor*, the CERCLA Section 121(d)(2)(B)(i i) restrictionon the use of ACLs as cleanup standards does not applyat this site. ACLs are "relevant and appropriate"requirements for the grocndwater cleanup at the Seynoursite, except for those contaminants with a maximum concentra-tion 11«rt t listed at 40 CFR Section 264.94(a)(2) (discussedabove) that are sufficiently protective of human healthand the environment. When the overall health based cleanupstandards of 1 x 1U'5 at the site boundary, 1 x 10'* atthe nearest receptor, and the HI of 1 are met, by definitionthe concentrations of the trie individual contaminants in thegroundwater Mill not present a threat to hunan health andenvironment. Those residual concentrations are the ACLs.

3. Background Levels - RCRA groundwater protection regulationsrequire that the concentration of a hazardous constituentmust not exceed background or the listed maximum concen-tration llnrtt or the ACL. Tn*e listed maximum concentrationlimits for barTuJn, lead and cadniun, must be met at thesit*. ACLs for other contaminants'will be based on therwjlnlng concentration of a particular contaminant in they round water at the time the overall level of protectionfor human health and the environment is met. Backgroundlevels are therefore not relevant and appropriate cleanupstandards for the Seymour site.

C. Water Quality Criteria (WQC) Established Under the Clean Water Act

The Clean Water Act Is not legally "applicable" to the groundwatercleanup at the site, with the exception of pretreatment requirements(discussed below) for discharge of :reated groundwater to the SeynourMOTW. Wi th this exception, there is no current or planned point

40

source discharge from tne facility to surface waters. Section 121 (d)(?) of SARA requires remedial actions to attain WQC wnere the criteria • }are "relevant and appropriate under tne circumstances of the release v J

or threatened release." This determination is based on the designatedor potential use of the water, the nertia affected, the purposes of thecriteria, and the latest info mat ion available.

The aquifers beneath the site are current and potential sources ofdrinking water, and the shallow aquifer at tines discharges to NorthwestCreek and the Von Range D1tcn. Therefore, WQC that have been adaptedfor drinking water only (In the Superfund Public Health EvaluationManual, Record *______) and WQC for protection of freshwater aquaticorganises are "relevant and appropriate" for the groundwater cleanupfor the site.

Other Standards Necessary to Protect Human Health and the Environment

In addition to these potential ARARs, the following non-promulgatedadvisory standards were considered in determining groundwater cleanuplevels that are necessary for chemicals for which there are no ARARsor where an ARAR 1s not sufficiently protective of human health .or the environment. =

*»

HA - Health Advisories developed under the Safe Drinking water Act forcontaninants not having a MCL. Health Advisories may apply to shorttern exposure, lony tern exposure or chronic exposure.

RfD - Verified Reference Doses developed by an 1ntra-agency EPA work- • Jgroup. These values represent an acceptable dally Intake of noncarcino-yenic cnenlcals (or, for a carcinogen, an acceptable dally intake ofthat chwnlcal considering Its noncarclnogenic toxldty). The corres-ponding acceptable concentration of a contaminant In drinking waterIs calculated by assuming that a typical 70 kg person drinks 2 litersof water per day.

Concentration (mg/1) « RfD(mg/kg/d)x [70 kg]/C2 1/d]

Pf_ - Potency Factors developed by EPA to characterize the potency ofa given carcinogen. These factors are used to estimate the IncrementalIncrease 1n cancer 1n a large group of people due to chronic exposureto a carcinogen at a given concentration. The calculations assumethat a typical person weighs 70 kg and drinks 2.liters of•contaminatedwater per day. Assuming a linear dose response curve (appropriate forrisk below 0.01):

Risk » PF((mg/kg/d)-l) x concentration (mg/1) x [2 1/d] / [70 kg]

Determination of Cleanup Standards

The MCls, which are ARARs for groundwater at the Seymour site, are usedas cleanup levels where available and where they provide sufficient

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protectloo of hunan health and the environment, taking Into accountcumulative health effects.

U.S. F.PA's policy on cleanup standards for Super-fund sites considersan excess lifetime cancer risk of 1 x 10-4 to 1 x 10-' to be an accep-table cleanup level-. (Se* July 9, 19«7 "Interim Guidance on Compliance«~h Applicable o* Relevant and Appropriate Requirements," page 9)(R*cord * . ) Tht exact excess cancer risk acceptable is basedon site specific circumstances. The 1 x It)'6 risk level has generallybeen applied at Supe.rfund sites 1n the past.

A. Carcinogenic Effects

As discussed above, ^Ls <»re ARARs for the groundwater cleanup at theSeymour site. At the. Seymour site, chloroform cleanup standards arehelng compared. to the MCL for total trihalonethanes because there isno specific standard for chloroform and 1t is a trihalomethane.

When determining whether MCLs and other standards are protective ofhuman health and the environment, the possible effects of simultaneousexposure to many contaminants were considered. For the carcinogeniccompounds with proposed MT.LS, the carcinogenic risk associated withthe proposal MCL was calculated using the potency factor. The cumula-tive risk fron exposure to these compounds is assumed to be additive,rather than synerglstlc or antagonistic. (See Super-fund Public HealthEvaluation Manual, October 1986) (Record » ) The additive riskof the six organic carcinogens «c their proposed MCLs Is 4 x 1U*4.The total excess cancer risk In the groundwater at the Seymour Sitefor all carcinogenic contaminants (Including those with no MCLs) wouldIncrease the 4 x 10"* risk because any concentration of a carcinogeniccontaminant has an associated risk. This total risk is not acceptablebecause it is not within EPA's acceptable risk range of 1 x 1U"4 to 1x 1U-7. (See FS Guidance and Superfund Public Health Evaluation Manual)(Record* ____ and $ ____ ) This cumulative risk level and anumber of other factors create a need for cleanup standards that aremore stringent than MCLs. These factors Include: a large number ofcontaminants (both carcinogenic and noncarclnogenlc) are present In thegroundwater and there Is a limited understanding of these contaminants'cumulative effect on human health and the environment; low levels ofcontaminants (below the MCLs) will continue to migrate when the extrac-tion system Is terminated; and the aquifer 1s a potential source ofdrinking water. A cumulative excess cancer risk that i« -nore stringentthan the MCLs Is therefore necessary to ensure sufflci .-.it >rotoctionof human nealth and the environment.

EPA has determined that a cumulative excess cancer risk of 1 x 1U~* forgroundwater cleanup *t the Seymour site must he attained at and beyondthe site boundary. This risk level is within the acceptable riskrange (I x 10~4 to 1 x 1U"7) and 1s appropriate for the circumstancesat the $Ue. A number of the circumstances justify this risk level.

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This is a conservative risk level that will provide protection ofhuman health. A more conservative risk level is not required to bemet at the site boundary because there must be provisions during thecleanup for Institutional controls on the area of the grcundwatercontamination plume; '.ie current land use of the area is agricultural;and the area is zoned industrial for any future development. Also,the groundwater 1s currently highly contaminated which makes It moredifficult to restore the aquifer.

Consistent with the FS Guidance, a 1 x 10-6 excess cancer risk must bemainf'ned at the site's nearest receptor. (Record *___) (See Fig-ure A.i; on page 9 for the location of the nearest current receptor inthe shallow aquifer) This more stringent cleanup standard is necessarybecause no contamination has been detected at this receptor to dateand the well is being used for watering livestock and possibly hunanconsumption.

The procedure that nust be used for calculating the excess cancer risklevel is detailed in the Superfwnd Public Health Evaluation Manual.(Record *______}

The cleanup level for groundwater was not determined considering thepotential carcinogenic effects from ingest ion of the groundwater1n combination with the risks from Inhalation of air or Ingest ion ofsoil. Simultaneous exposure to contaminated air and groundwater 1snot expected because of the prohibition on the use of groundwateruntil cleanup 1s achieved. The air emissions from the vapor extrac-tion system are expected to «uve ceased by the time the groundwater1s usable. If the vapor extraction system 1s still in operation,the cumulative excess lifetime cancer risk from air and groundwaterat the nearest receptor must not exceed 1 x 10~*. The soil 1s beingcapped, so any direct exposure to contaminated soil 1s eliminated.

In addition to meeting tn« total cumulative excess cancer risk level of1 x 10*' at the site boundary, the Individual MCLs for the carcinogeniccompounds must also be met. the compounds to be considered in thecalculation of the cumulative excess cancer risk and their HCL are:

benzene (MCL-5 ug/1) - methylene chloridechloroform (HCL-100 ug/1) - tetrachloroethene1,2 dichloroethane (MCL-5 ug/1) - 1,1,2 trlchloroethane1.1 dlchloroethene (Ma-7 ug/1) - tncnloroethene (Ma-5 ug/1)1.4 dloxane - vinyl c*1or1de (MCL-2 ug/1)

This 11st Includes all the carcinogens by the oral route of exposurethat have been Identified In the groundwater. This 11st of compoundsmust be revised If other compounds are identified as possible, probableor known human carcinogens.

The cumulative risk calculation shall be performed in accordance withthe methods being employed by EPA In the Super-fund Public HealthEvaluation Manual and subsequent revisions in effect at the time thecalculations are performed. The toxlcity data used shall be the mostcurrent data contained in the Superfund Public Health Evaluation Manual

4 o

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ar a«*)labl« fro* EPA's Cancer Assessment Group.

8. lion Carcinogenic Effects

For nonearcinogeflic chemicals there 1s also a need to establish anoverall cleanup leveVfur the ground water. Again this need arisesbecause of th* large number of contaminants In the groundwater. Themethod rtcoanentferi to address effects of multiple noncarclnogenlcchemicals Is th» chronic health Imtex (HI). The method Is defined Inmore detail 1n tue Superfund Public Health Evaluation Manual (SPHcM),Octooer 198f. (*ecord a )

The, qualifications to the HI process Identified 1n the Superfund PublicHealth Evaluation Manual are recognized. However, the HI process isa reasonable procedure to attempt to take Into consideration cumulativenoncarcinogenic health effects and will provide a conservative -leasureof the potential threat to human health from contaminants in the groundwater. Th« justification for using this approach 1s based on the sanesite specific circumstances described in paragraph A above regarding the1 x 13~* excess lifetime cancer risk level.

The total HI for the following compounds shall not exceed I.

- barluct (MCL-50 ug/1) - nethylene chloride- benze** (MCl-5 ug/1) - nickel- copper - phenol- 2-butanone - tetrachloroethene- caderiu* (MCL-10 ug/1) - toluene. chloroform • 1,1,1 trlchloroethane- ethyl benzene - xylenes- lead (MCl-50 ug/1) - vinyl chloride (1CL-? ug/1)- manganese

in addition, for those contanlnants that have MCLs, the MCL nust not beexceeded.

This 11st was developed 'roe compounds Identified and used In the endan-uement assessoert ^rformed as part of the RI. The 11st should beupdated as additional reference doses or other Information becomes avail-able and as HCLs art established for additional compounds.

•the calculation of the HI shall be perfomed In accordance with theSuperfund Public Health Evaluation Manual and subsequent revisions.Reference doses used In this calculation shall be taken from theSuperfund Public Health Evaluation Manual. (Record

The carcinogenic risk level is expected to be the ultimate factor forestablishing compliance with cleanup standards because of the lowconcentrations associated with excess lifetime cancer risk levels.

In summary, the ARARs for groundwater cleanup standards for both theshallow and <*«eu aquifer are the MCLs from the Safe Drinking WaterAct, the listed maximum concentration limits and ACLs as discussed at

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40 CFR Section 264.94, and the water qualit|f;; criteria established ( \ \pursuant to the Clean Water Act. V ./

In accordance with ERA policy (See "Interim Guidance on Compliance withApplicable or Relevant and Appropriate Requirements," dated July 9, 1987)(Record * ) tne icis are first considered as cleanup standardsfor the groundwater. However, because of cunulative health risks,tne MCLs were not sufficiently protective of human health. Therefore jhealth based standards of 1 x 10*5 cumulative excess lifetime cancer Ms*and a chronic health index not to exceed 1, are set for tne groundwatercleanup standard at the site boundary. Alt 10'* excess lifelinecancer risk must be met at the nearest current receptor. In addition,t^e iCLs must, at a minimum, be met for a particular compound at bothcompliance points. Alihougn specific concentration levels requiredfor cleanup are not established at this time, the cumulative riskcalculation and the chronic HI calculation are dependent upon theconcentrations present in tne ground water. The health based standardallows for evaluating different contaminants at different concentrationsthat may be present in the groundwater at the time when the groundwaterextraction system may be terminated. Different compounds will beremoved fran the groundwater preferentially. The mobility and original :concentration of a contaminant will be among the factors that determine «the time required for removal from the groundwater. Arriving at specificconcentration levels for individual contaminants based on the cumulativehealth risk is consistent with the requirement for an ACl under RCRAbecause they are protective of human health and the environment andbecause of the direct relationship between the health based standard !

and an associated concentration level. The factors in 40 CFR Part264.94(b) were considered when the cleanup standard was determined.

The cleanup standards are consistent with and more stringent thanthe water quality criteria for protection of human health for con-sumption of water only and for the protection of fresh water aquaticorganisms. The water quality criteria consider an excess cancer riskof I x 10'5 to 1 x 10"' for Individual compounds to be an acceptable riskrange. The cleanup standard requires a cumulative excess cancer riskof 1 x 10"5 at the site boundary, so excess cancer risks for Individualcompounds must necessarily be within the 1 x 10*5 to 1 x 10*7 rangeidentified In the water quality criteria docunent.

C. Compliance Point

The point of compliance for the ARARs, the 1 x 10*5 cumulative excesslifetime cancer risk level and the chronic HI of 1 1s at and beyondthe site boundary; or from a practical standpoint, the edge of thecap. The renedlal action Includes a multi-media cap over the site.Future use of the site 1s not envisioned, and deed restrictionsprohibiting use of the site are a part of the remedial action.Therefore, the aquifers do not become actual or potential sources ofdrinking water until they reach the site boundary. The site boundaryis therefore an appropriate point of compliance for groundwater (cleanup standards and is consistent with 40 CFR Section 264.95. Asecond compliance point for the NCLs, the 1 x 10-6 cumulative excesslifetime cancer risk and the chronic HI of 1 1n the groundwater is the

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nearest current receptor. The compliance points apply to both theshallow and deep aquifers.

0. Technical Impracticability

Tne possibility exists of not being able to technically neet the clean-up leweds. Therefore provisions for taking such a claim must be care-fully developed. Section I21(b)(2) of SAKA allows for a waiver, r,ene-rally the approach to a waiver of the cleanup levels based on technical^practicability should be based on Info mat Ion developed during theot*ratfon of the selected groundwater extraction and treatment system.A monitoring program must be carefully designed to develop needed in-fo mat ion. This Information must then be evaluated from both an overallqualitative perspective and a quantitative perspective. The qualitativeevaluation should, include, anong other things, water quality at extrac-tion and monitoring wells, possible modifications to the extractionsysten that could help achieve cleanup levels, and an endangerment assess-ment of the impact of discontinuing operation of the extraction systen.The quantitative evaluation should consider, anong other things, a statis-tical analysis of contaminant concentrations over time and the cumulativenass of contaninants oeing removed by the extraction systen compared toth« mass of contaminants remaining in the aquifer. The ground water modeldeveloped as a part of the RI iust be calibrated and verified for con.tarninant mass transport to aid in predicting aquifer behavior anddetermining if cleanup levels are met at the determined compliance points.

State AHARs

Based on Information supplied by the State of Indiana In an August 3, 1986letter from Harry John Watson III to Lawrence Kyte (Record *__), StateARAKS for groundwater at the Seymour site Include:

1. Narrative water quality standards and non-degradationstandards requiring waters to be fret of substances whichare acutely toxic or cause serious adverse physiologicalresponse, or are believed to be chronically toxic,carcinogenic, mutagenic or teratogenlc, and

2. Numerical drinking water standards for public water supplies.

The State of Indiana has not Identified these standards as more strin-gent than the Federal standards previously identified. Consistent witnthe State's narrative standards, the reconnended cleanup levels haveaccounted for chronic health threats.

Discharge

For discharge and subsequent treatment of extracted groundwater, the ARARsare dependent on the point of discharge. The Department of PublicWorks of the City of Seymour and IDE* have preliminarily Identified thepretreatment standards for the metal finishing and electro-pi atIngIndustry to be appropriate for discharge to the Seymour sewer systemof treated groundwater from the Seymour site.

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These pretreatmtnt standards are: V _ )

SUBSTANCE . MAXIMUM CONCENTRATION (mq/1)

Arsenic ' 1.0Cadnlun 1.0Copper 5.0Cyanide 1.0Lead 1.0Mercury 0.5Nickel ' 5.0Total Chromium 10. 0Zinc 10. 0Pneno's 0.5011 and Grease 100. uTotal Toxic Oryanics 2.13Total Suspended Solids* 13.4

•Average daily discharge for four consecutive monitoring days.

A TO re thorough evaluation of water quality and the POTW's ability to 'handle th« water must be performed as a part of the plume stabilization w

project and as a part of the final groundwater extraction systen.

This evaluation must ?>* consistent with 40 CFR 403.5 and local POTWregulations. The najor criteria considered in 40 CFR 403.5 are passthrough the POTW without treatment, interference with POTW operation,and contamination of POTW sludge.

In order to discharge frcm a Superfund site to a POTW, certain issuesidentified in an April 15, 1986 memorandum entitled "Discharge ofWastewater fro* CERCLA Sites Into POTWs" from Henry L. Longest,Director, Office of Emergency and Remedial Response, Rebecca Hanner,Director, Office of Water Enforcement and Permits, and Gene Lucero,Director, Office of Waste Programs Enforcement, to Waste ManagementDivision Directors, Region I-X and Water Management Division DirectorsRegion I-X, must be evaluated.

The first issue that must be evaluated concerns the compatibility ofthe discharge with the POTU. An evaluation of the anticipated waterquality that would reach the POTW 1s provided 1n the Work. Plan forthe Plume Stabilization Project. Because of the pre treatment beingprovided at the site prior to discharge, and the treatment and dilu-tion of the discharge at the POTU, no "pass tnrough" or interfer-ence with the POTW's operations or accumulation in the sludge is ex-pected. However, this will have to be verified by continued monito-ring. No hazards are expected to employees at the POTW- because ofthe pretre«tment of the discharged water. The air stripper IncludedIn the treatment scheme will greatly reduce the concentration of vOCswhich could cause a hazard to employees of the POTU.

The ijuantlty of water initially expected to be discharged during theplume staHUzatlon project is less than ISO gpn, which is approximately

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of the excess capacity of the Seynour POTU and approximately 15iof the average dally wastewater flow. The design capacity of thepkant Is 4.3 rullion gallons per day (ngd) and current average wastewaterfVoit Is 3.2 «gd. However, it has been noted from the Indiana Departmentof Environmental Management that hydraulic overloading of the plantoccurs during ami after periods of precipitation. (See correspondencefreft Jacquet.ne U. Strecker to David Favero, dated August 7.2, 1986)(Uncord • ____ ) Tnis factor must be taken into consideration whendetermining the operational parameters for the extraction/ treatmentsystem.

second point of consideration 1s the POTW's ability to ensure compli-e with applicable pretreatment standards and requirements. rhe Seymour

WTW has an approved pretreatment program. Monitoring reports will t>e pro-vided to the Seymour POTW. The monitoring will either be performed throughfunding of the St/perfund program, the State during the 0 4 M period, orresponsible parties conducting the remedial action with EPA oversight.

volatilization fron the wastewater 1s the next point to consider. Asstated above, an air stripper is a part of the selected treatment system.If determined to be necessary, air emission control equipment will be in-stalled on the air stripper. The potential Is low for significant volati-lization at tne POTW because most VOCs will have been volataltzed duringaor stripping. Should the air stripper not be included In the pretreat-amx. system because it is determined not to be necessary to meet pre-trwtment requirements, this point *ust be reevaluated.

potential for groundwater contamination from transport of thetreated groundwater or an Impoundment at the POTV 1s the next concern.Tfte potential exists for groundwater contamination along the sewersystem transporting the treated water. Again the pretreatment attne site minimizes any expected Impact of leakage from the sewerto the groundwater. The area of greatest potential Impact 1s fronthe site to the sewer's hookup with other lines from the Industrialpark. At that point mixing would further minimize any potentialimpact of leakage to groundwater. A portion of the sewer line**s Integrity tested during the plume stabilization project. The re-sults are being evaluated.

The potential of groundwater contamination from an Impoundment at thePOTri Is diminished because of the pretreatment at the site and theadditional treatment and mix at the plant. Groundwater monitoring ar

'tne POTU Is therefore not rec amended specifically as a result ofreceiving p retreated groundwater.

The next point of concern 1s the effect of water discharged from theSeymour site on maintaining water quality standards In the South Forkof the White River, the POTW's receiving stream. The results of theevaluation contained In the Plume Stabilization Work Plan Indicatetnat tne re will be no detectable levels of toxics In the discharge ofthe POTW. (See Plume Stabilization Work PI an) (Record i )Further evaluation of this concern will be performed. When now isincreased for the final remedial action, treatment must also be

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appropriate to assure water quality standards are maintained in , ;the East Fork of the White Kiver. V...>

The next point of concern is applicability of other environmentallaws at the POTW because it has received a discharge fro* a Super fundsite. All water discharged to the POTW wtll nix with domestic Mastealong the transportation route to the POTW. Therefore RCRA require-ments would not apply to the POTW. (See 40 CFR Section 261.4)Disposal of sludge is not anticipated to b« a problem but Mill beevaluated more thoroughly during the process of receiving authorization , j1to discharge. Monitoring of the sludge Mill continue after dischargeis started. No other environmental requirements have been identified •that Mould apply to the POTW because it is receiving wastewater :from a Suyerfund site. .

The last point of concern is the cost of managing Mater from a Super-fund site. Increased costs Mill be related to monitoring requirements. ;Parameters that are not currently monitored Mill be required. There !are potential costs associated Mith sludge disposal should the con-taminants accumulate 1n the POTW's sludge due to improper operationof the pretreatment system or should the current land application • ;sites refuse to accept the sludge. . fc ;

Based on the evaluations performed on the discharge of treated ground-Mater to the Seymour POTW, it was determined in the FS that this 1s aviable leans of managing the wastewater. An authorization to discharge-Hist be obtained from the City o' Seymour prior to any discharge to !the POTW occurring. The considerations 1n the policy on CERCIA dis-charges to POTUs will continue to be re evaluated as additional databecoaes available.

The public has been Informed of the U.S. EPA's Intention to dischargetreated groundwater from the Seymour site to the Seymour POTU. Nonegative comments were received. In addition preliminary contactshave been nade on this matter with the Director of the Seymour SanitaryDistrict, the City of Seymour Department of Public Works, the IDEMWater Division and U.S. EPA's Region V Water Division to ensure thatthe treated groundwater 1s discharged in compliance with applicablefederal, state and local laws. Additional coordination and documentsubmlttal will occur prior to actual discharge to the POTW. A con-sultant has been retained to represent the City of Seymour's interestin this matter.

If the discharge of created groundwater were to occur to '.he NorthwestCreek, the NPDES regulations would apply and a NPDES permit would benecessary.

If relnjection of treated groundwater or Injection of water from anothersource were to be incorporated Into the remedial action, the substantiverequirements of the UIC program would apply. A penult would not be neces-sary, however, because the injection would be an on-site action. This -»would qualify 1t for the permit exemption in SARA. \_)

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RCRA contains the ARARs for contaminated soil at the Seymour site. Closure ]and post-closure requirements of RCRA are not "applicable" to the remedialaction because tne facility ceased disposal of hazardous wastes prior toNovember 19, 1980. (See 40 CFR 264.1) RCRA's closure and post closure re-quirements are. however, generally "relevant and appropriate." The RCRAclosure performance standards set forth at 40 CFR Section 264.111 are ,narrative and state: '

The owner or operator must close the facility in a manner that:t

(a) Minimizes the need for further maintenance; and

(b) Controls, minimizes or eliminates, to the extentnecessary to protect human health and the environment,post-closure escape of hazardous waste, hazardousconstituents, leachate, contaminated run-off, orhazardous waste decomposition products to the ground .or surface waters or to the atmosphere; and '

w(c) Complies with the closure requirements of this sutopart

including but not 11 mi red to the requirements of'.specific closure provisions for various types offacilities].

Closure standards for containers, tanks, surface impoundments, andlandfills are generally "relevant" and "appropriate" to the Seymour site.

The closure requirements for containers are generally relevant andappropriate because drums of waste material generated during the RIcontaining drill cuttings, groundwater and protective clothing meetthe RCRA definition of "container." (See 40 CFR Sections 264.170 and260.10).

The closure requirements for tanks are generally relevant and appropriateto the treatment units used to treat collected surface water runoff.(Set 40 CFR sections 264.220 and 260.10).

The surface Impoundment created to collect the surface .water runoffcauses the closure and post-closure requirements for surface Impound-ments to generally be relevant and appropriate. (See 40 CFR sections264.220 and 260.10).

Because the disposal of hazardous wastes occurred at tne site, the land-fill closure and post-closure requirements are generally relevant andappropriate for the Seymour site. One of the landfill closurerequirements that 1s specifically relevant and appropriate calls forplacing a cap on the disposal facility. (40 CFR Section 264.310 (a))A cap is part of the selected remedial action.

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As the State 1s authorized to inplenent the RCRA program. State require-ments are equivalent to Federal requirements. See 320 [AC 4.1-46-1et. sei). U.S. EPA has not been notified of any more stringent or broaderTrT'scope State requirements.

The land disposal restrictions of RCRA also apply to any off-site disposalof hazardous waste. (RCKA $ 3004(d) and ( e ) )

Contaminated sediment will be consolidated on the existing disposal area,which Is the entire fenced area of the site. The sediments must be de-watered, If necessary, prior to consolidation in order to comply witn theland disposal restrictions of RCRA. (See 51 Fed. Reg. 40572)

ijther relevant and appropriate RCRA requirements Include a notice inthe deed to the property (40 CFR §264.119), access restrictions (4QCFH 264.14 and 264.117), inspection requirements (40 CFR §§ 264.15 and264.117), and disposal or decontamination of equipment (40 CFR § 264.114).The remedial action selected for the Seymour site meets all applicableor relevant and appropriate RCRA requirements.

AIR

The air emission requirenents of the Indiana State Implementation Plan(SIP) Rule 325 IAC Article 8 Section 6 apply to sources that emit greaterthan 25 tons per year of volatile organic compounds (VOCs). The selectedremedy for the Seymour site is not expected to emit greater than 25 torsper year of VOCs to the air. Therefore, these requirements are notappHca&le. If emissions from the site were to exceed 25 tons per year'of VOCs, the technical, substantive requirements of the SP would apply.The requirement of Rule 325, Article 2 for registration of VOC emissionsources does apply and will be met.

Although there are no applicable emission standards, an evaluationof the air missions must be made to determine 1f they pre-sent an unacceptable threat to human health and the environment. Twocomponent*-of the selected remedy emit to the air: 1. the air stripperin the yround water treatment system and 2. the vapor extraction system.These two sources must be considered In combination and the potentialhuman impacts from the total air emissions from the site evaluated. Aswith the yroondwater cleanup standard, air emissions nust not exceeda 1 x 10-* excess lifetime cancer Ms* level or a chronic health Index(HI) of 1 at th« nearest receptor.

Also, consistent with the FS guidance and as explained on page 34,the cumulative excess lifetime cancer risk from exposure to contaminatedair and jroundwater should not exceed 1 x 10'6.

RADIATION

At another Superfund Site In Reylon V radon was discovered accumulatedon carbon adsorbers used 1n treatment of ground*sent at levels that pose a potential threat to henvironment. The radon was naturally occurring.

on carbon adsorbers used 1n treatment of groundwater. The radon was pre- / ~\sent at levels that pose a potential threat to human health and the . ;

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Recause of this finding, radon Mill have to be considered Inthe selected roMtfy. For example, soil gas sampling during the pre-designInvestigation phASC must be perfomed and monitoring of air emissions andcarbon used in any treatment process muse oe performed.

Radon must be factored into the calculations to detemine if the cleanupstandards fur air, described above, are met.

ENFORCEMENT STATUS

Negotiations witn the PRPs are on-going. As stater* in the site history,a lawsuit was filed in the Federal District Court for the SouthernDistrict of Indiana in 1980. In 1984 a case management order Masissued that provides the framework for negotiations between thedefendants and the United States. There are approximately sixtydefendants currently named by the United States in the ongoing suit.These defendants nave in turn added approximately sixty third partydefendants. Summaries of Information linking defendants to the siteand relative contribution of waste volume have been provided to Chedefendants.

negotiations are expected to continue into the fall of 1987.

COMMUNITY RELATIONS

The community of Seynour has been concerned about the Seymour RecyclingCorporation Site since 1976. A1r and surface water discharges, whichpeople in the area felt were responsible for detrimental publichealth and environmental Impacts, were migrating fron the site.

Evacuation of 100 hones was necessary in March, 1980 due to a chemicalreaction that released toxic fumes. As a result, U.S. SPA became in-volved with the site.

The community was relieved when the surface cleanup began 1n December,1982. A concern about drinking contaminated jroundwater still existed.In order to alleviate this concern, money fro* the court-held trustfund, established as part of a 1983 settlement between U.S. EPA andcertain potentially responsible parties, was used to extend the city'sMunicipal water system to the Snyde Ac-es subdivision.

U.S. EPA has provided regular updates to the Interested parties. Inaddition, Important documents and information have been placed In threerepositories 1n Seynour.

On October 9, 1986, U.S. EPA held a public meeting In Seynour to discussthe results of the RI and FS and to answer any questions and receivecomments from the public. The prevailing concern of the public In regardto the remedial action seemed to be getting the action Implemented assoon as possible.

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For i«ore infomatlon on ccmunity relations, see the ResponslvenessSummary, Appendix 2.

. . FUTURE ACTIONS AND SCHEDULE

Future ace Ions and a 'urelininary schedule for their implementation areshown 1n Appendix 1. The schedule will no doubt go through many modifi-cations as negotiations progress and the project becomes more thoroughlydefined in the design and implementation.

ATSOR COMMENTS

The Agency for Toxic Substances and Disease Registry (ATSDR) perfomeda health assessment for the Seymour Recycling Corporation as required 3ySection of !04(1)(6Ha) SARA. The health assessment memorandum is datedApril 2, 19%7. (Record * ___ ) The report concludes that nopopulation is at present known to be exposed to hazardous substances'ran the site. The primary potential risk associated with the on- andorf-site contaminants 1s the possibility for chronic toxldty and/orincreased risk of cancer via low-level, repeated exposure should ther.o- action alternative be chosen. ATSDR also stated that all the alterna-tives considered by £PA, except no action, and EPA's recommendedalternative are considered adequate to protect human health basedupon the data presented.

Specific recommendations Included 1n the memo, pending the Implemen-tation of a suitable runedial action alternative, are:

1. Periodically monitor airport well «S and the nearestoperational downgradient water supply well for vola-tile organic contaminants. If or when volatlles aredetected, reassess the potability of the supply andtn* likelihood of endangerment to any remaining areawell*. This nay necessitate the extension of waterlines to affected or potentially affected residences/

2. Post signs 1n the contaminated crea of northwest creekIdentified for sediment removal to restrict recreationalactivities.

At such time as the suitable remedial action alternative f$ Implemented,dust control should be Instituted for those surface areas disturbedby removal /const ruction activity to minimize tne production of berylliumcontaminated airborne participates.

APPEMDIX 1

PROJECTED SCHEDULE FOR FuTiJRE ACTIONSAT THE SEYMOUR RECYCLING 3UPERFUND SITE

PHASE - ?lune Stabilization Project

Activity

Conclude Negotiations for thePlume Stabilization Project

Install Plira* Stabilizationwell

Initiate Construction of aTemporary Sroundwater TreatmentSystem

Complete Aquifer Tests

Operate and Maintain tneStabilization System

PHASE - Negotiations for Remedial Design

Activity

Receive Proposal for Site Cleanup

Complete tne Government's Responseto tne PRP Cleanup Proposal

Conclude Negotiations

PHASE - Implementation of RO/RA

Activity

Complete Design of GroundwaterCleanup Component

Implement Groundwater CleanupComponent

Complete Oesljn for Soil CleanupComponent

Implement Soil Cleanup Component

Projected Date

November, 1986 (Actual)

September, 1987 (Actual)

Fall, 1987

Fall. 1987

On-golruj

(RD) and Renedfal Action (RA)

Projected date

December, 1986 (Actual)

January. 1987 (Actual)

Fal l , 1987

Projected Date

Winter, 1988

Spring, 1989

Spring, 1989

Fall, 1989

54

ATTACHMENT 2

INDEX OF THE ADMINISTRATIVE RECORD

SEPTEMBER 28, 1987U.S. EPA. REGION VCHICAGO, ILLINOIS

55

WASHINGTON, O.C 204*0/ -S.\ UNITtO $TAT£S CNVIRONMCNTAL PROTfCTIOW AGtNCVA \ X*y^^ * IA* AAft-Jl ft4«* V«%&« Pfc *• *A^*A

<JSEP 28 s.-

SOBJKTi OMK Concurra>nca on th« R«cord of Decision for th« S«ymourlacycliag Corporation Sit*, S«ymour» Indiana

PBGMs G*f» Luc.ro, Dir»ctoc/O^ct Lu£fr*Offic« of Wast* Progrlaa tnforcwnant

TOi Valdut V. Adankua, AdainiatratorK«gion v

on th« August 31 ROD brinfing, and th« connaunicationa

and follovup analysis eonduetsd by our «taffs» I concur on th*rscocd of decision for th« Ssymour Kscycling Corporation sits asstipulated in th« "Twslth Ksnsdy DsLsgation Rsport - Part Two*

(Play ltr 1997).

cci J. Winston PortsrJack McGrawRuss wysrBill Constantslos

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