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HomeMy WebLinkAboutBozeman Solvent Site Background Testing CommissionMemorandum REPORTTO: HonorableMayorandCityCommission FROM: TimCooper,AssistantCityAttorney SUBJECT: Considerationofcompletinganoff-sitestudytoestablish sitespecific backgroundconcentrationsofPCEagainstwhichtocompareresultsofthe indoorairvaporinvestigationfortheBozemanSolventSite. MEETINGDATE: November23,2009 AGENDAITEMTYPE: Action RECOMMENDATION: BasedupontherecommendationofJeniferS.Reece, Esq.of Moore,O’Connell&Refling,P.C.(servingasoutsidecounselformattersregardingtheBozeman SolventSite),IrecommendthattheCityCommissionmakeadeterminationtonotcompleteanoff-site studytoestablish sitespecificbackgroundconcentrationsofPCEagainstwhichtocompareresultsof theOffsiteIndoor-air,Sub-slabVaporandOutdoorAirInvestigationfortheBozemanSolventSite. BACKGROUND: TheBozemanSolventSiteisthesiteofaninadvertentreleaseofperchloroethene (PCE)fromaformerdrycleaningoperationlocatedatwhatisnowknownastheHastingsShopping Center.ThePCEreleasewasfirstdiscoveredin1989.Sincediscovery,thesitehasbeenregulatedby theMontanaDepartmentofEnvironmentalQuality(MDEQ).TheCityofBozeman(City)andCVS Pharmacy(CVS) sharejointresponsibilityfortheBozemanSolventSite. Atthistime,astudyintheneighborhoodsnorthoftheHastingsShoppingCentertoevaluatethe potentialforvapormigrationfromgroundwaterimpactedbyaformerdrycleanerisbeingconducted bytheCityandCVS.Thefirstphaseofthevaporstudyinvolvedcollectingandtestingsoilvapor samplesalongCitystreetsandalleysbetweentheHastingsShoppingCenterandOakStreet.The resultsofthisfirstphase showedthatPCEwaspresentinsoilvaporatconcentrationshigherthana soil vaporrecommended screeninglevel(RSL)establishedbytheMDEQ. ExceedingthesoilvaporRSL doesnotmeanthereisanindoorhumanhealthhazard,butitdoesmeanthatfurtherinvestigationis appropriate. Becauseasoilvaporscreeninglevelwasexceeded,theCityandCVS,underthedirectionofthe MDEQ,areproceedingwithanadditionalphaseofthestudy. Thisnextphasewillinvolvecollecting indoorairsamples,andsoilvaporsamplesfromjustbelowthefoundation,inabout20homesand H:\20028\007\JSR5802.DOC  businessesnorthoftheHastingsShoppingCenter.Theresultsofthisnextphaseofthevaporstudy willshowwhetherPCEispresentinindoorairofthestructurestested,andifso,whethersuchPCE concentrationsexceedtheMDEQ’sindoorairRSL. ThoughtheCityandCVSinitiallyproposedconductinganoff-sitestudytoestablish sitespecific backgroundconcentrationsofPCEagainstwhichtocompareresultsoftheindoorairvapor investigation,basedonMDEQ’sindicationtheywillnotconsiderbackgrounddata,an understandingoftheMDEQ’sevaluationprocess,therisksinvolvedandtheexpenseofthestudy; Ms.ReecerecommendsthattheCitydoesnotcompleteabackgroundindoorairstudyatthistime. IfthebackgroundstudyiscompletedwithoutMDEQcooperationandapproval,MDEQhasno obligationtorecognizetheresultsofabackgroundstudy.Tothatend,completionofabackground studybytheCitywoulddonothingtoassistinreachingclosureoftheBozemanSolventSitebythe MDEQ.Additionally,MDEQ’sdecision-makingprocessinvolvesindoorairandsub-slabvapordata only.Consequently,thatprocessexcludesconsiderationofandalleviatesmuchoftheneedfor backgrounddata.Additionally,therearealsorisksassociatedwithcompletingalocalbackground studyforindoorairconcentrationsofPCEwhichmustconsidered. Finally,therearebackgrounddataprovidedfrom studiesacrossthenationthathavebeenpublished inpeer-reviewedjournalsandarereliable. ThoughtheMDEQwillnotrecognizesuchdata,theCity canrelyonandutilizethesestudiestoaddressanypublicconcern. FISCALEFFECTS: Theestimatedcostofcompletingabackgroundstudyisapproximately $125,000.BecauseMDEQwillnotrecognizethedataobtainedinabackgroundindoorairstudy andduetotherisksinvolvedingeneratingsuchdata,CVSisnotpreparedtoassistincoveringthe expenseofabackgroundstudyatthistime. Theexpenseofcompletingabackgroundstudycouldbe coveredwithintheexistingbudgetfortheBozemanSolventSite.However,todosoandremain withinbudget,itwouldverylikelybenecessarytoforegoremediationactionthathasbeenproposed includingadditionalbioremediationpilottestingandvaporextractiontobecompletedatthe HastingsShoppingCenter. ALTERNATIVES: Aviablealternativeatthistimeistopostponeconsiderationofcompletinga backgroundindoorairstudyuntilafterthecollectionofdatapursuanttotheOffsiteIndoor-air,Sub- slabVaporandOutdoorAirInvestigationapprovedbytheMDEQ.Receiptofthatdatawillprovide significantinsightintotheviabilityofcompletingabackgroundstudyandwillalsoreducetherisks associatedtherewith. Attachments:none Reportcompiledon:November18,2009 H:\20028\007\JSR5802.DOC