Document 6Bq4OKd60K9rMGq2N5KBB22Gd

CoumTOR KENT 14708 SEA, Roo(isSniegmriseAen.arLm.co6omr fd TAFT, STETTINIUS & HOLLISTER LL 1800 FIRSTAR TOWER 425 WALNUT STREET CINCINNATI, OHIO 45202-3957 aned dtal ra ol inion Fa5x13s.i38a1s.a28r3a8zs tats eerie ARA26 -- 1/80 May 7,2002 TELECOPY CWhersitsNVeirgglienyi,a EDseqp.artment Of Environmental Protection Office OfLegal Services 1356 Hansford Street Charleston, WV 25301 Pam Nixon Environmental Advocate West Virginia Department of Environmental Protection 1356 Hansford Street Charleston, WV 25301 James Becker, M.D. Marshall University Center for Rural and Environmental Health 1600 Medical Center Drive Suite 1500 Huntington, WV 25701 `William Toomey Managerof Source Water Assessment Program `West Virginia Department of Health and `Human Resources Bureau for Public Health 815 Quarrier Street, Suite 418 Charleston, WV 25301 DWre.stDeVeiArgninniSatDaeaptsartment of Environmental Protection 1356 Hansford Street Charleston, WV 25301 - 8 = 3=5= ER = - Jan R. Taylor, Ph.D. National Institute for Chemical Studies 2300 MacCorkle Avenue, S.E. Charleston, WV 25304 Joan Dollarhide, Ph.D. Toxicology Excellence for Risk Assessment 1757 Chase Avenue Cincinnati, OH 45223 Barbara Taylor Director, Office of Environmental Health Services West Virginia Department of Health and Human Resources - Bureau for Public Health 815 Quarrier Street, Suite 418 Charleston, WV 25301 CONTAIN NE 000095 May 7, 2002 Page 2 Jennifer Seed U.S. Environmental Protection Agency 410 M Street, S.W. `Washington, DC 20460 Samuel Rotenberg, Ph.D. 3WC11) U.S. Environmental Protection Agency 1650 Arch Street Philadelphia, PA 19103-2029 Roger Reinhart U.S. Environmental Protection Agency Region IIT 1650 Arch Street Philadelphia, PA 19103-2029 John Wheeler, Ph.D. (E-29) ATSDR 1600 Clifton Road, NE. Atlanta, GA 30333 Janet E. Sharke, Esq. (3EC00) U.S. Environmental Protection Agency Region II Office Of Enforcement, Compliance and Environmental Justice 1650 Arch Street Philadelphia, PA 19103-2029 Garth Connor U.S. Environmental Protection Agency Region Ill 1650 Arch Street Philadelphia, PA 19103-2029 John Cicmanec, DVM U.S. Environmental Protection Agency 26 West Martin Luther King Drive Cincinnati, OH 45220 Laura Werner (3HS00) ATSDR U.S. Environmental Protection Agency Region III 1650 Arch Street Philadelphia, PA 19103-2029 Re: CAT Meeting To Discuss C-8 Screening Levels/Risk Factors Ladies and Gentlemen: Attached hereto is Section 6of DuPont's June 1999 RCRA Facility Investigation Report for its calcul Washington Works facility ations in support oaf 3 ppb in Wood County, "preliminary scre West ening Virgin level" ia, for which C-8 in sets forth drinking DuPont's water. `Although we assume that eachof you have been provided with a copyofthis document by 000109 May 7,2002 Page3 DuPont (we understand that the document was submitted to at least the USEPA and WVDEP back in 1999), we wanted to make sure that each of the CAT Team members is aware of the existenceofthis document in the publicly-avalable files. Thank you. ery uly yours, RAB/mdm Attachment obert AVBifott 000101  OSSPranaemtaeyrwtoss CERTIFIED MALL RETURNRECEIPTREQUESTED June 24, 1999 Mr. Martin Kotsch. : Project Manager U.S. EPA, Region Ill P1h6i5l0adAerlpchhiaS,trPeeAt 19103-2029 RE: Permit WVD045875291 Dear Mr. Kotsch: for yourPlreeavsieewfiannddenccolmomseendtt.he RCRA Facility Investigation (RFT) ReportofFindings Ifyou have any questions or comments, please contact me at (304) 863-4271. Very truly yours, Attachment CC: OMfrf.icMeaorfkWParsitdedyManagement WV-DEP 1356 Hansford Street Charleston, WV 25301 Mr. B. F. Smith, Chief* Officeof Waste Management Charleston, WV 25301 1356 Hansford Street * cover letter only R.L. Ritchey Sr. Environmental Control Consultant `Washington Works . MOfsf.icBeaorfbaWraatTearylRoers,oCurhcieesf ~~ WV-DEP 1201 Greenbrier Street Charleston, WV 25311 2) g : g EID109642 000102 @ RCRA FACILITY INVESTIGATION REPORT DUPONT WASHINGTON WORKS WASHINGTON, WEST VIRGINIA USEPA PERMIT NUMBER WVD04-587-5291 June 30, 1999 at WRT, Project No. 0D6W7205 Ei0sess 2 000103 SECTIONSIX ScreeningLevel Risk Evaluation 61 OBJECTIVES AND APPROACH "The overall objectiveofthis risk evaluation is to determine whether identified releases from the SWMUs area potential concern for human health or the environment and whether further `evaluation or action is warranted. In the screening-level health risk evaluation, concentrationsofconstituents detected in soil and groundwater were compared to generic health-protective screening levels for soil and `groundwater, in order to identify constituents and exposure pathwaysofpotential concer. The ecological evaluation focused on characterizing the habitat within the RFI study area and identifying whether complete exposure pathways exist between SWMU releases and significant ecological resources or receptors. This approach allows identification of the constituents and exposure routesofconcer early in the RFUCMS process, and avoids expending effort on minor constituents and exposure routes that do not influence overall risk (USEPA Region III, 1993). `The risk evaluation has been prepared consistent with the screening-level approaches outlined in the following documents: Q RCRA Facility Investigation Plan, DuPont Washington Works (DuPont, 1997). Q RCRA Facility [vestigation Requirements (included as Attachment D to the RCRA Facility Investigation Plan). Q USEPA Region IN Technical Guidance Manual "Selecting Exposure Routes and Contaminants of Concem by Risk-Based Screening" (USEPA Region III, 1993). Q USEPA Region III Risk-Based Concentration Table (USEPA Region III, 1999). Q USEPA guidance for ecological risk assessment (USEPA 1997; 1998a; 1998b). In keeping with the above guidance documents, the risk evaluation includes: Q Descriptionofon-asndaidjt acee nt land use (Section 6.2). . Q Evaluation of data used in risk screening (Section 6.3). Q Screening-level health risk evaluation, in which analytical data were comparetod generic health-based screening levels for soil, to drinking water criteria for groundwater, or to a background levels (Section 6.4). & Q 65de)n.tification of constituents and exposure pathways of concen screening step (Section 5 3 . Q Ecological exposure evaluation (Section 6.6). 2 po ) Q Summary and conclusions (Section 6.7). EID109687 sae Et 000104 [E-------- SECTIONSIX Screening Level Risk Evaluation 6.2 SITE DESCRIPTION AND LAND USE This section provides an overviewof land use at the Washington Works site and identifies pisotpernotviialdehduimnaAnttaancdhemceonltog1i,caLlanredceUpsteorRse.poArdtd.itional information on current and:future land use 6.2.1 On-Site and Adjacent Land Use `pTlhaentWwaashsifnigrsttocnonWsotrrukcstefdaciinli1ty94h8a.s bIteeocnctuhpeiesiste1o,f20o0nagcoriens,geixntduesntdriinalg aacbtoiuvittiaemsisliencaelotnheg itnhietial O`mhainoufRaicvteurrisnegvpeunrpmiolseessawensdtoisfcPoavrekreerdsbwuirtgh, pWavVi.ng,Morasitl otfrtachkes,afnacdilbiutiylidsidnegvse.loOppeednfaorreas include lawns, mowed fields, and a few areasof natural growth along portionsof the riverbank. Tsyhsetedme.veTlhoeperdipvoerrtbiaonnkotfstelhfelpiresopoeurttsyidies ftheencseedc,uraintdy afcecncees,sbiustriigsorreoguusllayrlcyonptartorlollleeddb.yTahseecurity rseicvuerribtaynkpaatrdojlasc,enatndtotthheerefaicsilliittlyeistoraetltartaicvteclaysiunaalccveisssiitbolres,dtoutehetroivtesr'lsoceadtgieon.and the regular Adjacent land use is a mix ofindustrial, commercial, agricultural, residential, recreational, and owapreenhsopuascee.s tAodtjhaecweenstti.ndNuestarribalyorresciodemnmteiralciaarleapsroipnecrltuideestihneculnuidnecGorEpoPrlaastteidcstoawnnd tofwo `Washington, whose easter extent is adjacent to the DuPont property, and individual homes and subdivisions within about amileofthepropertyto the cast, south, and west. Figure 2.2 showthe Washington Workssiteand adjacentlanduse. `The Washington Works facility will continue to be used for industrial purposes in the future. Likewise, adjacent land use is expected to remain a mix ofindustrial, residential, and other uses. Land use issues are addressedinmore detail in Attachment 1,Land Use Report. 622 Groundwater Uses i . `inTdhuesatlrliaulv,iamlutneircriapcaelu,nacnodnfriunrealdwaaqtueifresrupispltihees.priDnceipptahl troeggiroonaulndawqautifeerriasnadppirsouxsiemdatleoclayll6y0f.o0r70 febeedtrionctkheatmraoiungphllayn1t0a0refae,eatnBdGtSh.esAastuirnadtiecdaztoendeiinspraebvoiuotus30setcot4io0nfsoefetthdiesepr,eepxortte,ndDiunPgotnot `Washington Works operates several production well fields on the plant property that provide `(iAndOu0st8r,iaPlWpOr1oc)e,ss33w2at(eArQaUnSd-pPoWtOaLb)le, waantder33to6 t(hAeMpOl7an-tP(WpOo1ta)b,leinwathteerEaisstprWoevlildeFdiebldy).Wells 331 wOeflflssitoenwtehlelGfiEelPdlsasitnitchsesditoewlnosctarteedajmudsitrteocttihoenwiensctluodfeWealsehvienngitnodunstWroiralksanadnfdivtehepLoubbleeckwater ~~ 3 Public Service District (PSD) wel field located about 2.3 miles south (downriver)of the plant. 8 `CTohuenLtuyb(eLcukbePcSkDPpSrDo,vi1d9e9s9w).ateOrthteornperairvlayt9e9we%lolsfotrhesmpaolpluclaotmimounniinttyhiwseplolrsotifounnokfnWoowondstatus 3 wAetraechidmeenntitfi1e,dLdoucraitnigonaowfeWlellsleharecahd, PbruotttehcetyioanreArseuasspeacntdedDorfibnekiinnggWianatcetrivWee(lslese).Se-ction 4.3 of SEE cunmmsrnooencosn 6-2 000105 SECTIONSIX ScrLeeveelRinsk Eivalnuatgion As discussed in Section 5, pumpingofthe Washington Works well fields controls groundwater flow, so that groundwater affected by SWMU releases is contained on-site. 6.2.3 SurfaceWater - Surface water ofthe Obio River provides water to the cities ofParkersburg, West Virginia, and Belpre, Ohio, about seven miles upstreamofthe Washington Works facility. There are no permanent streams or surface water bodies on the main plant area at Washington Works. Precipitation in the main plant area is directed toward drains and storm sewers, which ultimately discharge to the Ohio River. Two drainage swalesthatconveysurfacerunoffto the Ohio River during rainyweatherarelocated on the property, one in the facility's southwest corner and the other on the extreme easter (upgradient) endofthe property. . `The for BGm ane dPr WIhavebeen excavated,backfilled,andresurfaced,sotherearenosurface `water impacts from these SWMUs. The slopesoftheRBL/ADP above the Ohio River are heavily vegetated, and the SWMUs have been covered with clean fill, so surface water impacts via surfacerunofffrom these SWMUs are considered negligible. As indicated in the previous `sections, SWMU-impacted groundwater does not discharge to surface water because of production well pumping. 6.24 Ecological Setting `The Washington Works siteitselfis largely developed and used for manufacturing activities, - `with manicured lawns, mowed fields, and afewareasofnatural growth along portionsofthe river bank. These areas provide a narrow and intermittent terrestrial habitat for a variety ofbirds, small mammals, and other animals. The upper terraces upstream and downstream from the plant are kept in grassland withsomesmall areasoftreesand brush. A small chestaut grove is being developed by the facility's Wildlife Habitat Enhancement Program, in conjunction with the `American Chestnut Foundation. `There are noknownrecordsofany federalorstate listed species in the vicinityofthe `Washington Works Site (West Virginia Divisionof Natural Kesources (WVDNR], 1999). In addition, no wetlands or critical terrestrial habitat were identified at the Washington Works facility during field observations conducted at the site. Section 6.6, Ecological Exposure ~ Evaluation, provides additional site-specific information about ecological resources and exposures at the site. a | = g =I _--_-- mE EID109689 000108 Cuma coven samen mon 6-3 SECTIONSIX Screening Level Risk Evaluation 63 DATAAND MEDIA EVALUATED S4.o3i.l aNnod qguraoluintydwaastseurraanncaelyotricqaulaldiattya ccoonltlreoclteidssduuersiwnegrteheidReFnItiwfieerdetdhaitscwuosusledd in Sections affect data. 4.2 and usability in risk assessment. -- Tsaabmlpelses6.c1oltlrecotuegdhbe6.t4wesehnow0atnhds2oi0lfdeaettaBiGnScluadttehdeinBtGhearnidskReBvaLl/uaAtDioPn.unTihte,sTehdeatdaewpethreoff2r0om feet is considered a conservative estimateof depthof excavation for future construction or utility work. Two soil intervals were evaluated: 0 to 2 feet (surface soil) and 2 to 20 feet (subsurface soil). Table 6.5 shows the groundwater data included in the risk evaluation. These data were from winavteesrtiqguaatliiotny:sKa1m6p.lePsWOco1l,leLc1te7d-aPtWtOhIe,fiAvMeOpTro-dPuWcOtiLo,n VweOlSl-sPsWaOmpLl,eadnddurLiOnAg-tPheWOR1F.T Water from these wells is used to supply process water to the manufacturing ares, and water from Wells. /AMO7-PWOI (336) provides potable water to the plant. Therefore, groundwater drawn from these wells is representativeofthe exposure medium to which humans are or could be exposed. 64 SCREENING-LEVEL HEALTH RISK EVALUATION Texhpeopsuurrepopsaetohfwtahyesstchraetemnianyg:bleevaeclohenacletnh ifsorkheuvamlaunathieoanltish taondidtehnattifmyatyhewcaornrsatnittufeunrttshearnd eprvoatleucattiivoensocrraecetniionng. lCevoenlsstiatnudenetnsviwrhoonsmeenmtaaxlimmeduimactohnactehnatrvaetnioonscodnostniottueenxtsceeexdceheeadlitnhg- Screening levels are concluded to pose no concern for human health and can be eliminated from further evaluation. Potential exposure to multiple chemicals and multiple media also is cscorneseind.ered in the risk evaluation, in order to strengthen conclusions drawn from the risk-based 641 Potential Human Receptors : . Human exposure to hazardous constituents released from the SWMUiss minimal or non- eaxnidstveentg,etbaetceadu(sReBtLh)e.y hHaovweevbeere,n rfoermtohveerdisaknedvraelguartaidoend iotrwpaasvaedss(uBmGe,dPtWhaLt,pAotDePnt)iaolrocno-vsietfeed hcounmsatrnucrteicoenptwoorrskienrcslupdeerfsotremwionrgkeexrcsa,voactciaosniownoarlk.treOsfpatshseesres, atlhoenogntshieteriwvoerrbkaenrk,isatnhde most exposed individual, because he or she is assumed to be present ona dily basis for the duration ofhis/her career. Therefore, evaluating presumed on-site worker exposure to soil at the SWMUs a is protectiveofconstruction workers and trespassers, whose exposure would be short-term and & intermittent. 3 Likewise, workers are the only receptors who are exposed to production well water. 8 Construction workers would not be exposed to groundwater during excavation because the water table is about 60 feet BGS. | =Tree?-- men EID109690 000107 comm ---- Ok SECTIONSIX Screening Level Risk Evaluation 642 Screening Levels Used in the Evaluation Soil data were compared to the following screening levels: Q USEPA Region II RBCs for industria sil (soil ingestion pathway) (USEPA Region II, 1999). The RBCS are based on a target excess cancer risk of 10 (1 in 1 million) and a ninonscoialncteharthwaozaurldd qbueoteixepnetc(tHedQ)toofpoosnee.noThaedvseerRseBCimsparcetpsretsoenhteaclhtehmiucnadlercotnhceenetxrpaotsiuornes conditions evaluated. Industrial soil RBCs wereusedbecause the cument and future use of thepropertyisindustrial (Section 6.2.1and Attachment 1, Land Use Report). Q A screening level for lead in industrial soil of 1000 mg/kg. This level is a conservative l(elvoewl)secsatlicmualtaetefdoruisnidnugstrUiSalEPsoAi'l sscrAedeunlitngLepuardpoEsxepso,sbuerceauMsoedietlis(b1e,l2o0w0 ttyopi1c,a8l0s0crmegenkien,g using default parameters) (USEPA 19962). Q Federal MCLsfordrinwaktei ron rtg he federal action level for lead in tap water. Q USEPA Region I RBCs for tap water (in the absence ofan MCL) (USEPA Region III, 1999). Q Preliminary screening levels for FC-143 in soil and groundwater (see Section 6.4.3). nCaemretlaiyn:potential exposure pathways are not included in the derivationofthe screening levels, Q Isnchraelcaatiinogn:levTehles iunsheadlaitniotnhipsaetvhawluaaytiiosnn.otNionrclaurdeedthienrethUeSEdPeAri-vsasttiaobnloifshtehed U"sSoiElP-tAo-asioirl" screening levels for an industrial scenario. However, neglecting the inhalation pathway irseansootnse.xpected to significantly affect the results of the risk screening for the following -- First, inhalation of non-volatile constituents (such as metals or FC-143) that are adhered to soil particulate matter usually does not contribute significantly to overall risk because air emissions from wind erosion are, on an annual average bEamsiiss,siorenlaFtaicvteolry (lPoEwF.) ofT1h:i3s2 xis 10prems'e/nktgedsoilin(UUSSEEPPAA'1s996dbe)f.aulWthePanrtaipcpulliaetde in the denominatorofan equation to estimate air concentrations of particulate matter, the resulting air particulate matter concentrations are negligible and usually do not contribute to overall risk. aa -- wSeecrondrleyl,ativvoellaytilienfcroenqsuteinttuleyntds,etsecutcehdasinmseotihly(lseenee Tcahblloerisde6.o1rtthrriochulgohro6e.t4h)y,leanned, 55 would not be expected to contribute to a significant inhalation hazard. Therefore, a tthhee isncdruesetnriinagl-lseoivlelRBriCsks eavraelucaotnisoind.erIeFdcosnusfftiictiueennttlyccoonncseenrtvraattiivoens(pirnotseociltievex)cefeodr the RBCs, the inhalation pathway may warrant consideration in the future. ses 000168 EIDI0%3! mmm commasmms 6-5 SECTIONSIX Screening Level Risk Evaluation Q DdeerrimvaatlioanobsfotrhpteioUn:SEPTAhesoidlerRmBaClsaubsseodrpitniotnhisexepvoalsuuarteionr.outAeltihsoungoht included this adds in the a small uscnrceeerntianign.ty tIon tchaesesscrweheneirneg cloenvsetlist,ueinttwicolncneonttrsaitginoinfsicainntlsyoilaffeexccteethde results RBCs, of the dermal absorption may warrant further consideration in the future. ~ : Q Migration to groundwater: Soil screening levels for protection of groundwater used as drinking water were not included in the risk screening evaluation because groundwater data were compared directly to drinking water criteria. 643 Derivation of Preliminary Screening Levels for FC-143 'USEPA-established screening levels are not available for FC-143. Therefore, preliminary shecarletehn-ibnagsleedveClosmamnuanliotgyoEutxsopoRseugrieoGnuIiTdIeRlBinCes(fCoErGs)oiolfa0n.d00g0r3oumngdw/amt'eraiwre(rHeasdkeerlilveLdabforroamtoary 1991). The CEG was developed by Haskell Laboratory to be protectiveofpublic exposure via the inhalation pathway. `The CEG was derived from the DuPont Allowable Exposure Level (AEL) for workers of0.01 mthge/ym'a.pplByo.thFotrheexAaEmLplaen,tdhtehAe ECLEGfoarrewohrekaletrhs-pirs o1t0ec0ttiivemoesftlhoeweerxtpohsauarneNcoonOdibtsieornvsetdo Ewfhfieccth LLeevveell iinnaa llaabboorraattoorryy aanniimmaall ifneheadliantgiosntusdtyud(yHaasnkdelils L1a,b0o00rattiomreys 1l9o9w1e)r.thTahneraefMoarreg,intahle AEEffLecits considered to be a safe level for workers potentially exposed for eight hours/day. To derive a level protectiveofsensitive subpopulations (such as infants and the elderly) and to account for a 24-hour/day exposure time, the AEL was reducedfurther bya safety factor often to accountfothe presenceofscasitive subpopulationsinthecommunity and again by a safety mfagc/tmo'ro.ftThhreereeftoorea,cctoheunCtEfGorias2c4o-nhsoiudre/rdeadypreoxtpeocstuirveeotfigmeen,erreasullptuinbgliicn etxhpeoCsEurGeostfh0a.t0c0o0u3ld include sensitive subpopulations,exposed24 hours/day. : `Emxgp/odsauy,reastosutmhienCgEaGn oifnh0a.la0t0i0o3n mragt/eomf' w2o0uml'd/dreasyul(tUiSn EaPnAalRleogwiaoblneIdlaidleyfaiunlttakreesoifde0n.t0ia0l6 _ ignrhoaulnadtwioanterratec)a.nFbreocmaltchuilsataeldlouwsaibnlgeUinStEakPe,Apdreeflaiumlitneaxrpyosscurreeenaisnsgumlpevteilosnsfofrosroiilndaunstdrial soil ingestion and residential groundwater ingestion. Tmagb/lkeg)6.a6nsdhfoowrsgrthoeuncdalwcautleartiuosnoedfapsredlriimnkiinnagrywastcreere(n0i.n0g03lemvegl/sL)f.orTFhCe-s1e43prienliimndiunsatrryiaslcrsoeielni(n1g20 levels were used in evaluating site soil and production well water data for FC-143. 3 2 EID109692 he -4 mn 000109 cum socmamar 6-6 SECTIONSIX ScreeningLevel RiskEvaluation 6.44 Results of Risk-Based Screening for Soil `Tables 6.1 through 6.4 show the sample analytical results for constituents detectedinsoil and groundwater and include the SLs for comparison. Table 6.7 summarizes the resultsofthe risk- based screeningforsoil. ~ `Table 6.7 shows that maximum observed concentrationsofall constituents at all SWMUs and soil intervals were well below their respective screening levels, with the exception ofarsenic t(hwahticcohnsitsiptrueesnetnstiantscooilncdeontnroattipoonssecaomhepaalrtahbcloentcoerbnacfkorgrwoournkderlsevveilsa)t.heTshoeirleifnogrees,tiitonispcaotnhcwlauyd.ed Potential exposure via other routes (.g., dermal absorption or inhalation) and possible additive effectsofmultiple noncarcinogens are alsonot aconcern. Maximum observed concentrations of all site-related constituents were lower than screening levels by factors often to one million, except for FC-143 and methylene chloride in the 2- to-20-foot interval at the RBL/ADP, where `maximum concentrationsofthese two constituents were lower than their respective screening levels by a factorofabout 2.4. Because maximum observed concentrationsofsite-related constituents are well below conservative health-protective screening levels, it is concluded that constituents in soil do not pose a health concern for workers or transient receptors. 6.45 Risk Screening for Production Well Water Table 6.5 compares sample analytical results from production well samples to MCLs or other Hiealth-based screening levels for drinking water. Table 6.8 summarizes the risk-based screen for production well water. In well AM07-PWO1, which supplies potable waterforthe plant, maximum concentrationsofall constituents were belowtheir respective drinking water criteria. To confirm this conclusion, a third round ofanalysis for FC-143 was conducted in May, 1999 (see Appendix D). Therefore, no unacceptable health risk would be associated with the observed concentrations in the potable water well. : In production wells providing industrial process water, maximum concentrations ofall constituents were also below health-based criteria for drinking water, with the exception of TCE in production well V0S-PWO1 and FC-143 in production wells K16-PWO1, V05-PWO1, and L04-PWO1. Specifically, the maximum concentration of TCE (22 micrograms per liter (ug/L)) exceeded the MCL of5 ug/L, and the maximum concentration of FC-143 (16.2 ug/L) exceeded its preliminary screening level for drinking water of3 ug/L (Table 6.8). For both constituents, `maximum concentrations exceeded their respective drinking water criteria by factors of four to five. Because water from these wells is not used for drinking, but rather for industrial processes a `such as non-contact cooling water or fire water where exposure is nonexistent or intermittent, it % `was concluded that the exceedancesofthe drinking water criteria by relatively small factors is 2 not likely to pose health concern for workers who may be exposed to process water. 2 EID109693 - en mmm 000119 conmsrmmnsoosssssmon 61 Se ECTe IONSIX ere Screenin0g LBeUveGlRSisYkEPvVaalluaattiioonR 65 SUMMARY OF CONSTITUENTS (HUMAN HEALTH) AND PATHWAYS OF CONCERN All constituents in all media evaluated were below health-protective criteria, with the exception ofTCE and FC-143, whose maximum concentrations in industrial process well water exceeded dcornicneknitnrgawtaitonesr icnriptreroicaebssy wfaactteorrsatoftfhoeuproitnotoffivues(ese(ewAhpipcehnidsiacmeisxBtuarneodfCw)a.teHorwfervoemr,Saevveerraalge `ttyphpreioscdeaulectxficooerneidwneadlnulscste)rsiwaailrlpelrnbooectelcsooswnwesaritdteehrra.endmaacxoinmceurmncfoonrcweontrrkaetriohnesaldtehteucntdeedrienxopnoesuwreellc.on`Tdhietrieofnosre, As demonstrated in Section 5, SWMU-impacted groundwater is contained on-site by production `well pumping and does not migrate off-site or to surface water. In summary, the identified releases from the SWMUs are not a concern for human health. Site- related constituent concentrations in soil (0 to 20 feet) did not exceed screening levels. While TinCduEstarniadlFpCr-oc1e4s3s swoamteerwh(bautt enxocteiendpeodtasbclreeewneilnlgwlaetveerl)s,itnhperreodiuscltiimointewdelelxpwoastuerreutsoedinfdousrtrial process water. In addition, SWMU-impacted groundwater is containoend site. TinhdeisceatfeisntdhiantgspoatreentsiuamlmeaxrpiozseudrienrFouitgeusrfeor6.s1i,tHruemceapntoErxsp(owsourrkeerPsa,trhiwvaeyrbEavnaklturaetsipoans.serT,haendf.igure construction worker) are cither incomplete or insignificant and that groundwater migration to surface water is an incomplete pathway due topumping. . 66 ECOLOGICAL EXPOSURE EVALUATION . "The ecological evaluation focused on identifying whether significant ecological resources`may `be exposed to site-related constituents released from the SWMUs. According1g to USEPA. gcruiitidcaanlcheab(iUtaStE(PsAuch19a9s7,we1t9l9a8nad,s 1o9r9f8ibs)h,erviaesl)u,edareeccorliotgiicaclaltoressusotuaricneisnagrpetohpoulsaettihoantsoefisthpeer pcrioveoisrde ohrabsittaatte, alirseterdefslpeecctiievse othfaptucboluilcdcboenceexrpnoss(eed.ga,ndwisludlsicfeepthiabblietatto fsoirteg-raemleateadnicmoanlsst)it,uoerntasr.e federal `tfeoTrrhreehssatbtriuitdaalythacarhbeaiatrfaaotc.rtetTrhihezeaetecicooolnlo(oggAiipccraaillleev6vaal1lu0ua7at,tiio1on9n9i9in)nc,cllupudrdieendcdtiahpeadlafloyyuaarlnSodnWgaMhthUesaopofarlfntidiefoslnudorfrrteohcueonndnpiarniogspsearn=tcye. adjacent to the river, which includes the RBL/ADP. 66.1 Exposure Areas and Media 2 Ssutrufdaycaeresao.ilTahtethPeWRIBLan/dABDPG iSs WthMeUonslyarpeotceonvteiarledecwoiltohgigcraalveelx,paosspuhraeltm,eodribuuimldwiintghsinanthdedRoEnTot 85 perxopvoisduereecmoeldoigiacoaflcohanbictaetm. surface water at th site. fSourbescuorlfoagciecasloilre(cgerpetaotresr, tahnadn2grofeuentd)waantdergrdoouensdnwoattedrisarcehnaortgteo 2 --=_T--eed =m EID109694 000111 cummmmrmncocm ma 6-8 SECTIONSIX ScreenlRimsktEvealvuaetioln 6.6.2 Habitat Characterizationatthe RBUADP TheRBL/ADP lies in anarrow bandbetweentheriverandthe mainmamfituring area. It runs `approximately 4,500 feet and rises 30 feet above the floodplain, coverigga pprtionofthe alluvial terrace on which the main plant is located. A layerofclean fill 6 to 36achesthick was placed over the RBL upon closiuntrhee 1960s. The southem sideofthe RBLiswithtihen active `manufacturing removed. The aproenadsanwderisecfoivlelerdeadwnidtchag pper d aa ondrbav uriele ndionwl gsc.ovTehreedwADiPtshwgearses:yc,ivoesgeetdatiino1n.988 and `The slopeofthe RBL/ADP is covered with hardwood trees, shrubs, grasanather dense `vegetation that has grownin the 30yearssince the landfill wasclosed.Tareas betweenthe RBL/ADLandtheriveris manicuredgrass,with a fewtreesandshrubs.At:thieupstreamendof the RBL, the grassy area gives way to natural vegetationoftrees and shubs:. Major vegetation species include beech, maples, oaks, ash, cottonwood, black willow, anfiswectgum. `Wildlife observations, including tracks, burrows, and scat, includedsoulmammals (woodchucks, cottontail rabbits, squirrels) and deer tracks along portiooftmhse river. It can be assumed that other small animals such as mice, voles, raccoons, and vastus reptile and amphibian species would inhabit the area near the riverbank. Birds obsaved in the area were `primarily bank swallows, crows, and redwing blackbirds. Otherpasserimetiirds will likely occur `during different seasons. Hawks were observed hunting over the area auiseveral species of `waterfowl were observed on the river that might feed on vegetationon eriverbank. Ospreys, reintroduced by DuPont's Wildlife Habitat Enhancement Program, wemreported by a plant employee to nest in the area. Bluebird and wood duck nesting boxes were.placed near the river, but these species were not seen. 6.6.3 Identification of Significant Ecological Resources `While numerous plant and animal species were observed along the rivebank area, no. significant ecological resources such as wetlands, game habitat, or threatened or eafimgered species were. identified within the RFI study area. In addition, according to the WVDNR, Wildlife Resources Section, no rare, threatened, or endangered species are recorded forthevicinity of the . Washington Works plant. Table 6.9 lists the terrestrial speciesthat areEsted asRare,Threatened or Endangered (RTE) by both the U.S. Fish and Wildlife and the West Virginia Natural Heritage Program. In conclusion, no significant ecological habitat or species ofspecialconcern were identified `within the study area, and therefore potential ecological impacts from constituents in soil at the 'SWMUs are expected to be insignificant. a =g 8 EID109695 - =n commascoca 6-9 000112 SECTIONSIX Screening LevelRiskEvaluation 6.6.4 Ecological Exposure Pathway Evaluation In conclusion, there appear to be no significant ecological resources or exposure pathways of concern related to soil at the SWMUs. Groundwater is not an exposure medium for ecological receptors, because there are no surface expressionsofgroundwater at the site (water table is about 60 feet BGS). , . `These findings are summarized in Figure 6.2, Ecological Exposure Pathway Evaluation. The figure indicates that potential soil exposure pathways are either incomplete or insignificant, primarily due to the absenceofsignificant ecological resources in the study area. 6.7 SUMMARY AND CONCLUSIONS Soil at all SWMUs is not a mediumofconcern for human health because maximum observed `concentrations insoilwere below health-protective screening levels. In the well supplying potable water (AMO07-PWO1), constituent levels were below MCLs or other health criteria, so the `water is not a significant sourceofexposure for workers. In wells supplying industrial process `water, maximum concentrations oftwo constituents somewhat exceeded MCLs or health criteria for drinking water, but the water is not ingested, and therefore, the production well water is not considered a health concern under exposure conditions typical for industrial process water. SWMU - impacted groundwater is contained on site by production well pumping. Ecological habitat in the study area is limited to a narrow bandof woody or grassy vegetation along the river bank and slopesofthe RBL/ADP, inhabited or visited by small mammals, birds, and other animals. No significant ecological resources were identified within the RFI study area, and no rare, threatened,orendangered specieshavebeen recordedfor thevicinityofthe. `Washington Works site. Because ofthe absenceofsignificant ecological resources and the limited potential for exposure, ecological exposure pathways were concluded to be incomplete or insignificant. `Table 6.10 summarizes the findingsofthe screening-level risk evaluation and ecological exposure evaluation. : B - man, EID109696 Ccummwsrmsmnoocamsoann 6-10 000113 z8 33 8 mr TAB4s FC.13 R"ERSCURLATFSAFCOILRIGTRYIONUVNEDSWTIAGTAETRIOSNAMPLING DUPONT WASHIWNORGKTS POLANNT GroundwaterReve forNovemberSemple GrouRnesdowFabaratSuempr [[R5 mboortwwoerz[Tr7srilior rmJJeouaasn]]tc Joloiao1JT7z) [[Ar abaoonswmewwoornf[usremllcsa_sJswuw oJcnunoofoaosmfooofroosmsa|ll| [[[AmRcieosrasaivavveeerr [rrrmiiommsefeooosasaomtttl]]t]solJJolooirrsoo|| |rsr|| |[[[AAAEwcreaosawrvoonrr[[ouamunmsmwsilloaonsxsss JJfuuuoonntfflooemmsooolulosorrl||oo|s||T [[Aevrosra-piwwoorr_fo[u_agr[tam]]remmJfoosorrl[tihs| | [[aevnoanwsor [roswor rmmfs ugal ] Jo or|r|[roshwer [uaalsnfjmuuannafjoommsooolloos1r|fiz|| amma juonfomw|lor| [efroeeorrwwroorrmr[awrmomere_sf[ofomvooosrttta]]]mllsffoirotrr| [is| sn||[[[coLiroeskesrwvwoonrr [ {usmamlo eslzsro,mJfjooh ouoannjfjoi oxosossJoae ilss||los||o|l [[ioaorsrtrwwoovrrrer re_e srmJa oot ooomtttl ]]]aiJfle oosrron [[ |s| s||[o[ tokesnwwooC rr[|amai isnomJ_Je fuuusaonrnffflon ooaruzemsefsfosloorsa no|s]Ti||| [ioswonromt oanl ] foor|r| eavesammsla Juno fi [| [[iFooscaavvoorz [mrinmom ooortp ]] fio||o|| o[Nwesnww[ or_[osm fmueorrsi_JJJb osuo||iz||s ([(rpPoesoaivvceoorz--r[r[mimrsemoJJooomooonnni]]] iifnwioon|o|||r||[[[rrpoeeeswshivwvooorarJ[[somsvaloeolmJiJusuaa_annllssuJfafsoiosnc||lzn||s| [forooeasaivoer [ {rrimmfJmm ooooitn]]alJbel so||ses| [[owreenmvofro_a[mzsusJsuolnae_rfJfumrys||nf||o CCrE fsosavor [riTsEs7a C e Joon]n fw||-- [S2 ashwes [PoC sO feu7osrEiLlfCiioo|n|| [fferoosispstwserarf -- --[ ni i mJfJz i oool ooonnm o ]!--fojt e oo orrr|| [e s|| |[[[ruvisaxessaevwoerr[[ fmaemsie onse fjJm uouooonnrfobori omemfaorra |||||| Bees Trvieniis oor|P]age 1012vwswor [zamlisr_(vsrlomlaon|l fH 4 090114 Gvmctxs fen F143 RERSCURLATSFFACOIRLIGTRYOIUNNVEDSWTAITGEATRISOANMPLING DUPONT WASHIWNORGKSTPOLANNT GroundterResa forNovemberSump GrouRnevdowFebaruartySeemprlog (([VzVivoeasanwtvwwooorrr--r T[rie iniJTa Jmoooooonngsn]yi soTJloipars| s 1i|rs|| | [[frumioeesmwwwoonrr_l[|psemmsmleooluresss:sfoJoauootnrllfooeomoamntflleoaormnnsll|||| fs f22roracirwocrn--Jorcoitn]nc gJmosss |h|s [z2 ones[zum2o1lzos fognl8o2mtlaons PrimaryScrsnogLevel(5 3wp g onzoon1o Pogozet2 000115 Gwe xs Tans | ES EEE TA EEEE miTEE NnTlOLE e E wHH iere e amT e seial EE ee t =p He fe eerweere E= mTEEdFrdae rE,dire IilFeCEel e e BEBE es e eee E Pr --r I REE ee nes BEEEcA sossn onesie somsrsaesm wszomo rt TABLE 6.6 CALCULATION OF PRELIMINARY SCREENING LEVELS --. FOR FC-143 IN SOIL AND DRINKING WATER Rnauaeyw [Coos| 20 |" oo6 | 2 | oom | 0 J wews| a0 | LBegeend:ecay nakeay= SGcoEriGngnoavtnedRatie n var= botDaly take Wate rein te PSLsod =PreliminaryScreeningLevelforindustrialsoi = AllowableDaily intake x 10 mg/kg /Soi IngestionRate .B1E5 a CNaimmeapCSaoanmnmaavcE-kuEenancroGumidhaalaaoinnatre,sesxoUSEenPA(RsakgaalnLa,bo9rat7ory, 191) Co Rorevmraorsnonewvassteoosysla rgetniorrme r(wGeSEiPgnAasagainIi, 1(5U9S)EPA Rg 1, 199). meesoy ersSot ren Ft. 23 EID109782 000117 EEE eePE TEaT = fEneem | |i [carbonTeuscrionse |NO (024) E"S EE [AN , Epoe [wll e TE] FTHE rieereeE . RE aren FI wR-ElSan ren ---- 2 2 sone worse Coser HEALTH-BTAASBELDE6S8CREENING --_ FOR PRODUWCELTLI WAOTENR Foe| wat | say|semongtom noe|sesso| [ev loo ar [oom se rcooo)m | macmm ta mon 0 (008) lFe-1as wt 102 roscnocayane | vor. renaceryens w = 2 =w] et oos wer "o pPraotciYeeos0s) s we| owe s wet| Pprocsst-:vtaotso) o Noi) soo nec LPGaSEgUanP:raisimaryCSonctarmiengantLLovoevsooegTraelin6.w6a2t0ed.Secon 8.42. RhBtCimRaakibnassed conan or 33 water USEPA Region, 1999 e0)teWre:n 338 Avr owor) @K)ipreoctesswatervets p(iirroen VLoisrevwoorr VLosowwonr Loeowor (06) FTr1c4h3ioxetycaosaaoxecaseaedkdeednnhaerMy LSk.ip nprodr uciena wweell KVdOISG-PPo HOOY1, VOS-HO410d, LOLA a z Smt tam EID109784 000119 Fatt - = RISK EVATLAUBALTEI6O.N10RESULTS ] Do Constituent Levels Pose Pateatial Concera? [ExposureMedium |Sol0-7f |SoliZ-30%| Groundwater | fPwisel [No [Wo | | [PrPootcabeleWWaateerrwWeells 0s1)[ T| w No | [SWMUTmpaciedGrowndwaier||C| omamedonsie | (1) Natoe=)Alwlrceonbsteiltouwenltecvoelnscenhatrawtoiounlsdwbeereexbpeelcotewdhealptohssec&receonnincgerleuvenldseorrm(ferrinidusttriealxpproosceessduring wmiatnhiTnctihueiRnFgI sotruadtyiacrena.. Mhee were no significant ecological esouorrl.iecd pees denied (2) 3) PProotcaeblseswwaatteerrwweelllls==WKelIl6-3P6WO(LA,MLOITT-.PPWWOOL),.VOS-PWOL, LO4-PWOL. ga2 EID109786 000120