chevron case: re 25 public short expert report (nov 7, 2014)
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1.0INTRODUCTIONThisSupplementalExpertReportrespondstocommentsofClaimants,ChevronCorporationandTexacoPetroleumCompany(hereaftercollectively,Chevron),onmyopinionscontainedintheRejoinderExpertReportofJeffreyW.Short,Ph.D.RegardingActivitiesandEnvironmentalConditionsintheFormerTexaco‐PetroecuadorConcession,RepublicofEcuador(hereafterShortDecember2013RejoinderReport).IreaffirmmyopinionsexpressedinmyDecember2013RejoinderReport,andprovideadditionalevidencetosupporttheseopinionsinthisSupplementalExpertReport.Inaddition,IofferheresupplementalopinionstoaddressissuesraisedinthethreerebuttaldocumentsfiledbyChevronlistedabove. ****2.0MATERIALSREVIEWEDI have been retained by the Louis Berger Group, Inc. (hereafter Louis Berger) to review and comment on the above Chevron documents. I have also been retained to interpret data from the chemical analysis of soil, sediment and water samples collected by Louis Berger from oil contaminated sites in Chevron’s former Concession Area during the spring and summer of 2014. In preparation of this Supplemental Expert Report, I have reviewed the following:
ExpertOpinionofJohnA.Connor,P.E.,P.G.,B.C.E.E.RegardingRemediationActivitiesandEnvironmentalConditionsintheFormerPetroecuador–TexacoConcession,OrienteRegion,Ecuador,ResponsetoLBGReportofDecember2013,Issued7May2014(hereafterConnorMay2014ResponseReport),
SecondExpertReportbyRobertE.Hinchee,Ph.D.,P.E.,Issued9May2014
(hereafterHincheeMay2014ResponseReport),
TheMatterofAnArbitrationUndertheRulesoftheUnitedNationsonInternationalTradelaw;ChevronCorporationandTexacoPetroleumCompany,Claimants,v.TheRepublicofEcuador,Respondent,Claimants’SupplementalMemorial,Track2,Issued9May2014(hereafterClaimants’May2014SupplementalMemorial),
Louis Berger’s Supplemental Expert Report, Issued 7 November 2014,
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Preliminary results1 of chemical analyses for hydrocarbons produced by Axys Laboratory, Katahdin Laboratory, and Battelle Memorial Institute provided to me by Louis Berger,
all scientific literature and deposition documents cited herein,
numerous chemical analysis reports produced by Dr. Gregory Douglas at Newfields Environmental Forensics Practice, and associated chemical analysis reports produced by Alpha Woods Hole Group and Severn Trent Laboratories.
I am currently an independent consultant and have never been an employee of Louis Berger or of Winston & Strawn LLP. My opinions in this expert report are given to a reasonable degree of scientific certainty. They are based on my education, professional experience, information and data available in the scientific literature, and information and data about this lawsuit identified herein and in my earlier report. I continue to review available information, and I reserve the right to amend or supplement this report and the opinions contained in this report on the basis of any subsequently obtained material information. ****3.SUMMARYOFSUPPLEMENTALOPINIONS3.1ResultsfromLouisBerger’sSamplingin2014ConfirmMyPreviouslyExpressedOpinions:
MeasurementoftotalpetroleumhydrocarbonsbyMethod8015B–themethodemployedandrelieduponbyClaimants’experts‐detectslessthan20%ofthepetroleumactuallypresentincontaminatedsoilsandsedimentsinformerConcessionAreaoilfields.
USEPAMethod418.1wasmuchmoreaccuratefordeterminingtheextentof
petroleumhydrocarboncontaminationinformerConcessionAreaoilfieldsthanwasMethod8015B.
Theweatheringstateofpetroleuminsamplescollectedin2014waslittlechangedfromsamplescollectedin2013,consistentwithmyprioropinionthatpetroleumweatheringisnowlargelyarrestedintheformerConcessionArea.Giventheseresultsandtheobservedconditionsofcontamination,Ido
1AsofthewritingofthisreportthelaboratoriesandLouisBergerhadnotyetcompletedvalidationofthe2014samplingdata.
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notbelievethatweatheringwillnaturallyremediatethecontaminatedareastoanappreciableextentwithinthenextfewdecades.
3.2BasedonMyAnalysisofResultsfromLouisBerger’sSamplingin2014,IConcludetheFollowing:
TheaveragenaturalbackgroundoforganicmaterialextractablewithdichloromethaneinsoilsandsedimentsoftheformerConcessionAreaisabout160mg/Kg,andisalmostcertainlylessthan400mg/Kg,whichisnegligibleformostconcerns.
Thenaturalbackgroundfortotalpolycyclicaromaticcompounds(totalPAC)
insoilsandsedimentsoftheformerConcessionAreaismostlikelylessthanabout0.05mg/Kgandalmostcertainlylessthanabout0.1mg/Kg,
ThenaturalbackgroundfortotalpetroleumhydrocarbonsmeasuredbyMethod8015B(TPH8015)insoilsandsedimentsoftheformerConcessionAreaismostlikelyabout50mg/Kgandalmostcertainlylessthan100mg/Kg,
WhenPACsandTPH8015aredetectedabovebackgroundconcentrationsthedetectedcompoundswerealmostcertainlyderivedfrompetroleumthatwasoriginallyproducedattheoilfieldwheresamplingoccurred,
Petroleumcontaminationingroundwatersamplesispredominantlypresent
aswhole,free‐phaseoilratherthanascompoundsdissolvedfrompetroleum.
MostpetroleumdetectedinthesamplesanalyzedwasonlymoderatelyweatheredbutstillfluidatambienttemperatureswithintheformerConcessionArea,andcouldbereadilydispersedintowaterandtransportedbygroundwater.
3.3CriticismsbyDr.RobertHincheeofMyPriorReportsareWithoutMerit:
ContrarytoDr.Hinchee’sclaims,theToxicityCharacteristicLeachingProcedure(TCLP)asappliedintheformerConcessionAreawasnotintendedtoevaluatethemobilityoffree‐phaseoilinsoilsandsediments,butTCLPwasinsteadappliedaccordingtotheprocedurespecifiedforevaluatingdissolutionofoilcomponentsintoreceivingwater.
ThemostimportantconsequenceoftheflawedmethodusedbyDr.Hinchee
andMr.Connortoevaluateoilweathering,thatIpointedoutinmypreviousreport,isthegreaterfluidityimpliedbytheless‐weatheredoil,enablingittobemorereadilytransportedinground‐andsurfacewaters,nottheeffectthis
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errorhadontheirinferencesregardingthesolubilitiesofoilcomponents,arelativelyminorconcernincomparison.
Dr.HincheeobjectstotheweatheringscaleIusedtoevaluatetheextentof
weatheringofpetroleum‐contaminatedsamples,yetthisistheverysamescaleusedbyChevron’sownexperts,onwhoseinterpretationsandreportsDr.Hincheehimselfhadpreviouslyrelied.Also,Dr.HincheesimplyignoresfundamentalprinciplesofscientificinferencewhenheconcludesthattheLouisBergersamplesfrom2013showsignificantadditionalweatheringcomparedwithsamplescollectednearlyadecadeearlierfortheJudicialInspections.
3.4ComparisonofToxicPolycyclicAromaticCompoundsinPetroleumfromtheFormerConcessionAreaandBunkerOilfromthePrestigeOilSpill
IcompareddistributionsofrelativePACabundancesinBunkeroildischargedduringthePrestigeoilspillofftheSpanishcoastin2002withun‐weatheredShushufindicrudeoiltoconfirmthattheybroadlysharedthesamesuitesoftoxicPAC,whichvalidatestherelevanceoftoxicologicalstudiesperformedafterthePrestigeoilspilltoconditionsintheformerConcessionArea.
****4.0SUPPLEMENTALOPINIONS4.1ResultsFromLouisBerger’sSamplingin2014ConfirmMyPreviouslyExpressedOpinionsResultsfromchemicalanalysisofsamplescollectedfromtheformerConcessionAreaduringLouisBerger’s2014samplingcampaignconfirmopinionsIsetforthinmypreviousreport2.Someofthecollectedsoilandsedimentsampleswereanalyzedbythreemethods:(1)USEPAMethod8015Bfor“totalpetroleumhydrocarbons”(TPH,hereafterdenotedasTPH8015),(2)gravimetricallyfortotalextractablematerial(TEM)basedondichloromethaneextraction(whichIrecommendedinmyearlierreport3),and(3)USEPAMethod8270forpolycyclicaromaticcompounds(PAC),alkanesandpetroleumbiomarkers.Theseanalyseswereperformedonportionsofthesamesamplessothattheresultsaredirectlycomparable.Theresultscorroborateseveralconclusionsinmypreviousreport4.
2ShortDecember2013RejoinderReport3Ibid.4Ibid.
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ThegravimetricTEMmethodisespeciallysimple,involvingextractionofpetroleumintodichloromethane,separationoftheextractfromsoilorsedimentparticlesbyfiltration,evaporationofthedichloromethaneandweighingthepetroleumresidueleftbehind.ThisgravimetricTEMmethodisanadaptationofUSEPAMethod413.1,OilandGrease(gravimetric,separatoryfunnelextraction)5.Theadaptationsinclude:(1)useofdichloromethaneastheextractionsolventinsteadofthenowbannedtrichlorotrifluoroethanespecifiedinMethod413.1;and(2)applicationtosoilsandsediments.ThismethodforgravimetricdeterminationofTEMwassuccessfullyusedtoquantitativelydetermineresidualpetroleumonbeachesofPrinceWilliamSound,Alaska,12yearsafterthepetroleumwasdepositedbythe1989ExxonValdezoilspill6.Theseandothercloselyrelatedmethods,includingUSEPAMethod418.17,ASTMD7066‐048,andAPHAStandardMethod5520Band5520C9allusechemicallysimilarextractionsolventsintowhichpetroleumcandissolvecompletely,andusedetectionmethodsthatcandetectallthelow‐volatilitycomponentsofpetroleum(i.e.byinfraredspectroscopyorbygravimetricweighing)10,sotheyproducecloselycomparableresults.ComparisonofTEMresultswithTPH8015resultsconfirmsthatMethod8015Bdetectslessthan20%ofthepetroleumactuallypresentinsamplesofsoilsorsediments.ThisfindingisillustratedinFigure1,whereresultsforTPH8015areplottedagainstthegravimetrically‐determinedTEM.Theregressionlinecoefficientr2of0.96indicatesthatthegravimetricTEMmeasurementaccountsfor96%ofthevariationintheTPH8015measurements.Theregressionlineslopeof0.189indicatesthatMethod8015Bdetectsabout19%ofthepetroleumactuallypresent.Atlowerlevelsofpetroleumcontamination,thisregressionslopedecreasesto0.124,indicatingdetectionofonly12%ofthepetroleumactuallypresent,consistentwiththetrendtowardgreaterweatheringinlesscontaminatedsoilsandsedimentsnotedinmyearlierreports11.ThisfindingisexpectedbecauseMethod8015B5seehttp://www.cromlab.es/Articulos/Metodos/EPA/400/413_1.PDF6ShortJW,LindebergMR,HarrisPM,MaselkoJM,PellaJJ,andRiceSD(2004)EstimateofoilpersistingonthebeachesofPrinceWilliamSound12yearsaftertheExxonValdezoilspill.EnvironmentalScienceandTechnology38:19‐257ThismethodwasdiscontinuedbyEPAbecausevaporsfromthetrichlorotrifluoroethaneusedastheextractionsolventdepletesatmosphericozone.8AmericanSocietyforTestingandMaterialsInternationalMethodD7066‐04isareplacementmethodforEPAMethod418.1anduseschlorotrifluoroethylene,9TheAmericanPublicHealthAssociationStandardMethod5520foroilandgreasedeterminationprovidesforbothgravimetric(Method5520B)andinfrared(Method5520C)detectionofoilandgreaseextractedfromsamples;seehttp://www.standardmethods.org/store/ProductView.cfm?ProductID=4110AmericanPetroleumInstitutePublicationNumber4709(2001),Risk‐basedmethodologiesforevaluationpetroleumhydrocarbonimpactsatoilandnaturalgasE&Psites,p.3511ShortDecember2013RejoinderReport;ExpertOpinionofKennethJ.Goldstein,M.A.,CGWPandJeffreyW.Short,Ph.D.RegardingtheEnvironmentalContamination
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cannotdetectasubstantialfractionofthecrudeoilpresent,forreasonsstatedinmyearlierreport12.Moreover,thisundetectedfractionincreasesascrudeoilweathersfollowingreleaseintotheenvironment.Theseresultsalsocorroboratethegreaterthan4:1DRO:TPHrelationshipbetweenMethod8015BandTPHasdeterminedbyUSEPAMethod418.1anddiscussedinourfirstreport.13
Figure1.ComparisonofTPH8015andTEMbygravimetricextractioninsoilandsedimentsamplescollectedfromtheformerConcessionAreaduringspringandsummer2014.Furthermore,thePACsfoundinthesamplesindicatethattheTEMinthesesamplesisalmostalwaysweatheredcrudeoil.ThisfindingisillustratedinFigure2,whereresultsfortotalPACareplottedagainstthegravimetrically‐determinedTEM.Theregressionlinecoefficientr2of0.65indicatesthatthegravimetricTEMmeasurementaccountsfor65%ofthevariationinthetotalPACmeasurements.Theregressionlineslopeof0.00528indicatesthatonaveragetheweatheredcrudeoilinthesamplescollectedcontainedabout0.53%totalPAC,comparedwith0.85%
FromTexpet’sE&PActivitiesintheFormerNapoConcessionAreaOrienteRegion,Ecuador”(hereafterLouisBerger,2013)12ShortDecember2013RejoinderReport13LouisBerger,2013,p.35‐37
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typicalofun‐weatheredOrientecrudeoils.14ConcentrationsoftotalPACthatwerelowerthanexpectedonthebasisofthegravimetricTPHarealmostcertainlytheresultofweatheringlosses.TheweakerassociationoftotalPACwithgravimetricTEM(65%)incomparisonwiththeTPH8015byMethod8015BandgravimetricTEM(96%)mainlyreflectsthegreatersusceptibilityofPACstoweatheringlossesincomparisonwithcrudeoilcomponentsmeasuredbyMethod8015B.
Figure2.TotalPACconcentrationsinsoilandsedimentsamplescollectedfromtheformerConcessionareaduringspringandsummer2014.ThesestrongcorrelationsbetweenTPH8015byMethod8015BandtotalPACwithgravimetricTEMindicatesthatconcernsraisedbyChevron’sexpertsthatMethod418.1issusceptibletoseriouspositiveinterferencesfromnaturallyoccurringorganiccompoundsinenvironmentalsamplesareconsiderablyoverstated.AsInotedinmypreviousreport15,substantialinterferencesofthissortareunlikelybasedonsimplemassbalanceconsiderations.ResultsfromtheLouisBerger2014samplescorroboratethisview.SubstantialinterferencesfromnaturalsourcesoforganicswouldbeevidentinanomalouslyhighconcentrationsofPACoralkanehydrocarbons,withabundancedistributionsdifferingmarkedlyfromthosetypical
14AlphaWoodsHoleGroup,laboratorysamplenumber0406054‐01atGSD305171,identifiedasShushufindiSuroesteoilatGSD207000(hereafterGSD305171)15ShortDecember2013RejoinderReport
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ofpetroleum,andthatareassociatedwithhigherconcentrationsofgravimetricTEM.Instead,thestrongassociationofTPHmeasuredbyMethod8015BandTPHmeasuredgravimetricallyasTEM(Fig.1)showsthatcontributionsoforganicsfromunknown,naturalsourcesaregenerallynegligibleintheOriente,especiallyaftermakingappropriateallowanceforweatheringontheMethod8015Bresults.Finally,gravimetricTEMconcentrationsinsoilsorsedimentsaboveabout2,000mg/KgareaccompaniedbybiomarkerdistributionscharacteristicofOrientecrudeoils,andconcentrationsabove1,000mg/KgarealmostalwaysassociatedwithPACabundancedistributionscharacteristicofcrudeoil.TheseresultscorroboratetheargumentIpresentedinmyearlierreport16thatinterferencefromnaturalsourcesisnegligibleincomparisontocrudeoilcontaminationabove1,000mg/Kg.Consequently,resultsbasedonMethod418.1shouldnotbedismissedonthebasisofspeculativeassumptions,nowclearlyshowntobeincorrect,andespeciallynotindeferencetoMethod8015B,whichisshowntobesusceptibletofarworsebiastowardsfalsenegativeresults.
4.2GeneticRelationshipsAmongPetroleumContaminants
Thepetroleumbiomarkerfingerprintsareremarkablyconstantthroughoutthesamplesanalyzed,basedon16diagnosticbiomarkerratiosrecommendedforfingerprintingcrudeoils17(Table1).Thisindicatesthatallofthesoilandsedimentsamplesanalyzedforpetroleumbiomarkershavecrudeoilsources,mostlikelyfromtheirrespectiveoilfields.Theslightdeparturesthatdooccurfromtheoverallbiomarkerfingerprintaremostlikelythecombinedresultofvaryingsusceptibilitytoalterationthroughweatheringprocessesandvariationassociatedwithlowbiomarkerconcentrationsasdetectionlimitsareapproached,althoughcomparisonoftwodiagnosticratiossuggestrealdifferencesinthebiomarkerfingerprintscharacterizingtheAguaricoandShushufindioilfields(Table1).Conversely,thereisscantevidenceofthepresenceofpetroleumfromsourcesoutsidetheOrienteoilfieldsofEcuador.ResultsfordiagnosticbiomarkerratiosarelistedinTable1forsoilandsedimentsamplescontainingatleast2,000mg/KgTEMasmeasuredbythegravimetricmethodtoensuresufficientbiomarkerconcentrationsforaccuratedeterminationsofalltheconstituentbiomarkersusedtocalculatetheratiosdetected.Table1.Petroleumhydrocarbonbiomarkerusedforcomputationof16diagnosticratiosandtheirrangesinsoilandsedimentsateachofthethreeformerConcessionAreaoilfieldssampledduringspringandsummer2014.Numbersinparenthesesfollowingtheoilfieldlabelsindicatethenumberofsamplesincludedfor16Ibid.p.1417DalingPS,FaksnessLG,HansenABandStoutSA(2002)Improvedandstandardizedmethodologyforoilspillfingerprinting.EnvironmentalForensics3:263‐278
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determinationoftherangeforeachoilfield.BiomarkerrangesinboldfaceindicatepotentialdifferencesinthebiomarkerfingerprintsofcrudeoilsfromtheAguaricocomparedwiththeShushufindioilfields.
4.3WeatheringStateofPetroleumContamination
MostsamplescollectedbyLouisBergerin2014,whethersoils,sedimentsorgroundwater,containedpetroleumattheKaplanandGalperin(1996)18weatheringindexof5,indicatedbyextensivelossesofvolatilecompoundsandofn‐alkanes,butonlyslighttomodestlossesofPACs,mainlynaphthalenes(Tables2–4).Severalsamplesweremoreweathered,havingweatheringindexesof6or7,indicatedbymoreextensivelossesofPACs.However,somesampleshadaweatheringindexof4,indicatedbylossofmostn‐alkanesbutofscantPACs.Twosamples,collectedfromthesameboreholeatSSF‐13,hadaweatheringindexof2,retainingallbutthelightestn‐alkanes,suggestingtheoilwaseitherremarkablywellpreserved,ormorelikelywasspilledrelativelyrecently.Asexpected,thepetroleumcontaminatingstreamsedimentsisgenerallymoreweatheredthanpetroleuminsoils.Theweatheringindexforstreamsedimentsisoften6or7,whereasitisusually5andsometimes4orlessinsoils.Weatheringindexescouldoftenbeassignedtothemorecontaminatedgroundwaterandsurfacewatersamples,andwhenassignedwereusually5or6.19
18Kaplan,I.R.,Galperin,Y.,Alimi,H,Lee,R.P.,andLu,S.T.1996,PatternsofChemicalChangesduringEnvironmentalAlterationofHydrocarbonFuels,GroundwaterMonitoringandRemediation113–114(hereafterKaplanandGalperin1996)19WeatheringstateswereassignedwhentotalPACexceeded0.5mg/Kginsoilsorstreamsediments,orexceeded0.5ug/Lingroundwaterorsurfacewatersamples.Thesethresholdsforassigningweatheringstatesdonotreflectthresholdsforthe
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Overall,thesamplescollectedduringthe2014samplingcampaignshowlittleindicationofadditionalweatheringsincetheprevioussamplingcampaignconductedbyLouisBergerin2013.Thesamplestakenin2014furtherconfirmmyconclusionthatweatheringhasbeenlargelyarrestedforoilcontaminationintheOriente.AsIdiscussedinmy2013Reports20,thisismostlikelybecausethepetroleumhasbeenburiedwhereoxygenandotherconditionsconduciveforweatheringarelargelyabsent.Tobeclear,Ihaveneveropinedthatnoweatheringhasoccurred.Weatheringcansubstantiallychangethecompositionofpetroleumontimescalesthatrangefromhourstohundredsofyearsormore,inwhichlattercasetheweatheringratebecomes“largelyarrested”21.Irecognizethatsomeweatheringhasoccurredandcontinuestooccur,butmostlyatratesthatarenownegligibleoverthecourseofyearstodecades.Asaresult,whilesomevolatilefractionsofcrudeoilarenolongerpresent,othertoxicandcarcinogeniccomponents,likePACs,arestillpresentinsubstantialconcentrations.Giventheseresultsandtheobservedconditionsofcontamination,Idonotbelieveweatheringwillnaturallyremediatethecontaminatedareastoanappreciableextentwithinthenextfewdecades.4.4InterpretationofHydrocarbonAnalysesofFieldSamplesCollectedfromEcuadorin2014
4.4.1AmountandExtentofPetroleumContamination
Althoughconcentrationsvariedwidelyamongthesamplescollected,indicationsofheavypetroleumcontaminationwereevidentatallthreeoftheOrienteoilfields(Shushufindi,LagoAgrioandAguarico)wheresampleswerecollectedandanalyzedforpetroleumhydrocarbons.Lowerconcentrationsofoilcontaminationinsoil,sediments,andgroundwaterwerealsoevidentatthesesites.Incontrast,PACevidenceofsurfacewatercontaminationbypetroleumwasevidentonlyinwatersamplesfromtheLagoAgriofield,andtheconcentrationsweremodest(i.e.lessthan2.2g/LtotalPAC22,orpartsperbillion).Mostofthepetroleumhydrocarbonsinthesamplesarepresentaswholeoil,meaningoilasadistinctphaseseparatefromwater,ratherthanascomponentsofnaturalbackgroundofhydrocarbonsinsoils,sedimentsorgroundwatersoftheformerConcessionAreasoils.Thenaturalbackgroundconcentrationsareconsiderablylower.20LouisBerger,2013,ShortDecember2013RejoinderReport21LouisBerger,2013,p.6122TotalPACreferstothesumof48parentpolycyclicaromaticcompounds,PAC,andclassesofalkylatedPAC,rangingfromnaphthalenewithtwoaromaticringsthroughbenzo[g,h,i]perylenewithsix.Exceptingdibenzothiopheneandthealkylateddibenzothiophenes,theotherPACareallpolycyclicaromatichydrocarbons,orPAH.
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oildissolvedintowater.Thisassociationwithwholeoilisindicatedbytheconcurrentpresenceofaliphatichydrocarbons,especiallypristaneandphytane,whicharerelativelypersistentbranchedalkanehydrocarbons,alongwithPAC.Thisevidencesupportstheconclusionthatwholeoilismigratingthroughoralongwithambientmedia.
4.4.2ShushufindiSamplescollectedfromtheShushufindioilfieldcontainedsomeofthemostandleastcontaminatedsamplesofthe2014samplingcampaign(Table2).ThelowestconcentrationsamplesservetoindicatethebackgroundconcentrationsoftotalPAC,n‐alkanes,TPH8015andgravimetricTEMintheregion.Thehighestconcentrationsamplesincludetheleast‐weatheredsamplesanalyzed.Table2.Summaryofhydrocarbonanalysesforsamplescollectedduringspringandsummer2014fromShushufindioilfield,Ecuador.Analyticalresultsarepresentedasmg/Kgforsoilsandsedimentsandug/Lforwatersamples,allgivenwithtwosignificantfigures.
Site
TotalPAC
Totaln‐Alkanes TEM
TPHby8015B
WeatheringState23
DiagnosticBiomarkers24
Soils SSF13‐SL001 0.021 0.55 400 26 NA SSF13‐SL002 (1)25 0.027 0.77 100 28 NA SSF13‐SL003 0.030 1.3 120 10 NA SSF13‐SL004 (2) 0.026 0.53 92 41 NA SSF13‐SL005 0.032 0.27 140 9 NA SSF13‐SL006 0.020 0.22 250 27 NA SSF13‐SL007 0.69 2.7 760 39 5 SSF13‐SL008 0.022 0.40 80 9 NA SSF13‐SL009 0.036 0.47 80 9 NA SSF13‐SL010 1.85 100 47 5 SSF13‐SL011 (3) 650 2300 19,000 9,700 2 YSSF13‐SL012 (4) 2.0 1.2 710 90 5 SSF13‐SL013 (1) 330 23 NA SSF13‐SL015 (3) 660 2500 2 SSF13‐SL016 (4) 560 86 SSF13‐SL017 (2) 0.028 0.36 NA SSF25‐SL029 0.025 0.28 100 10 NA SSF34‐SL001 0.052 0.48 640 87 NA SSF34‐SL002 0.040 0.33 110 15 NA
23WeatheringstateisbasedonKaplan&Galperin1996.24Diagnosticbiomarkersymbols“Y”indicatesadefinitepetroleumbiomarkerfingerprintconsistentwiththepatternpresentedinTable1above;“Y‐“indicatesabiomarkerfingerprintindicativeofpetroleumbutprobablyalteredbyweathering.25Numbersinparenthesesfollowingthesiteidentificationlabelsincolumn1indicatefieldduplicatesamples.
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Site
TotalPAC
Totaln‐Alkanes TEM
TPHby8015B
WeatheringState23
DiagnosticBiomarkers24
SSF34‐SL003 0.054 0.20 120 15 NA SSF34‐SL004 0.051 0.55 130 17 NA SSF34‐SL006 0.083 0.90 120 38 NA SSF34‐SL007 0.076 1.4 360 25 NA SSF34‐SL008 0.068 0.61 1,700 24 NA SSF34‐SL009 4000 410 140,000 53,000 4 YSSF34‐SL010 630 63 33,000 7,000 4 YSSF34‐SL011 780 71 40,000 11,000 4 YSSF34‐SL012 0.91 1.7 150 80 5 SSF43‐SL001 15 31 2,300 1,200 4 Y Sediments SSF13‐SE001 0.048 0.40 930 12 NA SSF13‐SE002 0.075 13 26,000 30 NA SSF13‐SE003 1.2 9.3 880 75 7 SSF13‐SE004 (5) 1.4 9.9 39,000 460 7 Y‐SSF13‐SE006 2.6 38 1,500 77 7 SSF13‐SE007 0.65 8.6 2,200 100 7 Y‐SSF13‐SE008 0.86 13 1,100 54 7 SSF13‐SE009 1.7 33 2,000 140 7 Y‐SSF13‐SE010 0.74 3.0 320 27 6 SSF13‐SE011 (5) 2.0 17 11,000 330 6 Y‐SSF55‐SE001 (6) 900 211 53,000 14,000 5 YSSF55‐SE002 240 65 11,000 5,000 5 YSSF55‐SE003 3.3 9.3 2,700 230 5 YSSF55‐SE004 250 76 53,000 6,500 5 YSSF55‐SE005 80 60 30,000 2,800 5 YSSF55‐SE006 0.87 11 1,800 120 7 SSF55‐SE007 18 77 22,000 5,000 5 YSSF55‐SE008 150 69 50,000 5,900 5 YSSF55‐SE009 (6) 410 85 23,000 6,900 5 Y Groundwater SSF13‐GW001 0.75 12 130 6 SSF13‐GW002 (7) 0.44 2.4 130 NA SSF13‐GW003 0.52 3.5 200 5 SSF13‐GW004 0.32 3.1 39 NA SSF13‐GW005 (7) 0.53 3.4 150 6 SSF25‐GW008 0.25 7.9 210 NA SSF25‐GW009 0.19 1.7 39 NA SSF25‐GW010 83 11 2,100 5 SSF25‐GW011 11 1.9 1,100 6 SSF34‐GW001 (8) 0.19 7.6 53 NA SSF34‐GW002 0.22 21 55 NA SSF34‐GW003 0.28 46 61 NA SSF34‐GW004 0.23 21 110 NA SSF34‐GW005 (8) 0.17 5.9 43 NA SSF43‐GW002 0.18 1.9 140 NA SSF43‐GW003 3.4 3.1 210 5
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Site
TotalPAC
Totaln‐Alkanes TEM
TPHby8015B
WeatheringState23
DiagnosticBiomarkers24
Surface Water SSF13‐SW001 0.22 0.56 62 NA SSF13‐SW002 0.21 0.94 30 NA SSF13‐SW003 0.13 0.41 35 NA SSF13‐SW004 0.25 0.41 110 NA SSF13‐SW005 0.068 0.73 33 NA SSF13‐SW006 0.076 0.83 60 NA SSF13‐SW007 0.26 8.6 100 NA SSF13‐SW008 0.076 1.3 62 NA SSF13‐SW009 0.13 4.3 90 NA SSF13‐SW010 0.12 1.4 140 NA
4.4.2.1SSF‐13MostoftheShushufindisoilandsedimentsampleswerecollectedfromthissite.Ofthe14soilsamplescollectedandanalyzedforPAC,9hadverylowconcentrationsoftotalPACrangingfrom0.021–0.036mg/Kg(partspermillion;Table2).ThisconcentrationrangefortotalPACmostlikelyreflectsthenaturalPACbackgroundofsoilsandsedimentsintheregion.ThisnaturalbackgroundpatternofPACabundanceisdepictedinFig.3,andischaracterizedbyrelativelylittleincreaseofalkyl‐substitutedPACabundanceincomparisonwiththerespectiveun‐substitutedparentPACofahomologousseries,incontrasttosoilscontaminatedwithlowconcentrationsofpetroleum.PetroleumcontaminationintheLA16‐SL002sampleisindicatedbytheincreasedabundancesofthealkyl‐substitutedPACincomparisonwithrespectiveun‐substitutedparentPAC,bythepresenceofchryseneandthealkyl‐substitutedchrysenehomologues,andthelowabundancesoftheunsubstituted5‐ringPAH(i.e.BBF,BKF,BEP,BAP,GHI,DAandIND).26ThecomparisondepictedinFig.3suggeststhattheupperlimitforthenaturalPACbackgroundliesbetween0.040mg/Kgand0.16mg/KgtotalPAC.TheTPH8015concentrationscorrespondingtothisPACbackgroundarelessthan50mg/Kg(Table2),suggestingthatthenaturalbackgroundforTPH8015isalmostcertainlylessthantwicethisconcentration(i.e.100mg/Kg).Similarly,theTEMconcentrationscorrespondingtothePACbackgroundrangefrom80–400mg/Kg,withanaverageof160mg/Kg.
26Abbreviationsforthesecompoundclassesareasfollows:N=naphthalene,B=biphenyl,AY=acenaphthylene,AE=acenaphthene,B=biphenyl,F=fluorene,A=anthracene,P=phenanthrene,D=dibenzothiophene,FL=fluoranthene,PY=pyrene,BA=benzo[a]anthracene,C=chrysene,BBF=benzo[b]fluoranthene,BFK=benzo[k]fluoranthene,BEP=benzo[e]pyrene,BAP=benzo[a]pyrene,BP=benzopyrenes,PER=perylene,IND=indenopyrene,DA=dibenzoanthracene,GHI=benzoperylene;numbersfollowingPAHabbreviationsindicatethenumberofcarbonatomsofalkylsubstituents.
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Figure3.DistributionofbackgroundPACinsoil(bluebars)comparedwithasoilsample(LA16‐SL002)containingalowlevelofcontaminationbypetroleum(redbars).SoilsamplesfromthreeothersitesatSSF‐13hadtotalPACconcentrationsthatrangedfrom0.69–2.0mg/KgoftotalPAC.However,twosoilsamples,collectedfromthesameboreholeinsidethereservepit(i.e.SSF13‐SL011and–SL‐015),hadtotalPACconcentrationsofabout650mg/Kg,associatedwithatotaln‐alkaneconcentrationof2,300–2,500mg/Kg,aTEMof19,000mg/Kg(or1.9%)andabiomarkerfingerprintindicatingcontaminationbypetroleum.Theweatheringstateofthesesampleswas2,indicatinglossofvolatilealkanesandaromaticsbutlittleelse.Comparisonoftheratioofpristaneton‐heptadecane,orofphytaneton‐octadecaneshowslittledifferencefromrespectiveratiosofun‐weatheredShushufindicrudeoil,indicatinglittlebiodegradationhasoccurred.Theseresultsstronglysuggestthatpetroleumwasrecently(lessthanayear)dischargedtothesoilthatwassampled.Only2ofthe10samplesofstreamsedimentsfromtheSSF‐13sitecontainedbackgroundconcentrationsoftotalPAC,oneat0.048andtheotherat0.075mg/Kg.Concentrationsintheremaining8samplesrangedfrom0.65to2.6ug/g,indicatinglowbutclearcontaminationbypetroleum.
16
TotalPACconcentrationsinthe5groundwatersamplesanalyzedfromSSF‐13rangedfrom0.32–0.750ug/L(i.e.partsperbillion).Whilelow,theseconcentrationsindicateclearcontaminationofthesampledgroundwaterbypetroleum,confirmedbytheconcurrentpresenceofpristaneandphytane.TotalPACconcentrationsinthe10surfacewatersamplesanalyzedfromSSF‐13rangedfrom0.068–0.26ug/L,withPACdistributionsindicativeofpetroleumcontamination.
4.4.2.2SSF‐25Thissitewasmoreextensivelyanalyzedin2013andmyoverallconclusionsasrelatetothissiteareincludedinmyDecember2013Report.Imaintainthoseconclusions.Limitedsamplingwasconductedin2014atthissitewhichIdiscussbelow.ThesinglesoilsampleanalyzedfromtheSSF‐25sitecontainedonlythebackgroundconcentrationoftotalPAC(i.e.0.025mg/Kg).ConcentrationsoftotalPACin2ofthe4groundwatersamplescollectedfromtheSSF‐25sitewere0.19and0.25ug/L,andaswithsurfacewatersamplesatSSF‐13,havePACdistributionsindicativeofpetroleumcontamination.TwoothersamplescontainedtotalPACconcentrationsof11and83ug/L,indicatingclearcontaminationofthesampledgroundwaterbypetroleum,confirmedbytheconcurrentpresenceofpristaneandphytane.
4.4.2.3SSF‐34Sevenofthe11soilsamplesfromSSF‐34containedbackgroundconcentrationsoftotalPAC,rangingfrom0.028–0.083mg/Kg,withcorrespondingconcentrationsofTPH8015rangingfrom15–87mg/Kg.AlthoughcorrespondingTEMconcentrationswereusuallylessthan400mg/Kg,onesample(SSF‐34SL008)hadaTEMconcentrationof1,700mg/Kg,despiteconcentrationsoftotalPACandTPH8015of68mg/Kgand24mg/Kg,respectively.Thissamplewascollectedfrom3.3mdepthnearapit,andinspectionoftheMethod8015Bchromatogramrevealedanunusualbroad,largepeakspanningaretentiontimewindowofnearlyaminute,suggestingapossiblecontaminantassociatedwithaproductusedbyoil‐productionoperations,whichareoftenproprietary.Onesample(SSF‐34SL012)containedlow(0.91mg/Kg)totalPACthatwasclearlyderivedfrompetroleum,andtheother3wereheavilycontaminatedbypetroleum,withtotalPACconcentrationsrangingfrom630mg/Kgto4,000mg/Kg.InadditiontoaPACabundancedistributiontypicalofpetroleumcontamination,thebiomarkerfingerprintprovidesadditionalconfirmationofthepetroleumsourceforthesesamples.ThesamplefromSSF34‐SL009wasthemostcontaminatedofallthesoil
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andstreamsedimentsamplescollectedfromtheShushufindioilfield,andwithTEMat140,000mg/Kg(or14%)impliessoilthatisnearoratsaturationwithpetroleum.NostreamsedimentsampleswereanalyzedfromSSF‐34.The5groundwatersamplesanalyzedfromSSF‐34containedtotalPACconcentrationsrangingfrom0.17–0.28ug/L,generallyconsistentwiththelow‐levelpetroleumcontaminationPACpatterndepictedinFig.3.
4.4.2.4SSF‐43ThesinglesoilsampleanalyzedfromSSF‐43containedaconcentrationof15mg/KgtotalPAC,indicatingmoderatepetroleumcontaminationandconfirmedbythebiomarkerfingerprint.Oneofthe2groundwatersamplescontainedatotalPACof0.18ug/L,generallyconsistentwiththelow‐levelpetroleumcontaminationPACpatterndepictedinFig.3.Theothersamplecontained3.4ug/L,indicatingmoderatepetroleumcontamination.
4.4.2.5SSF‐55OnlystreamsedimentsampleswereanalyzedfromSSF‐55.Mostofthesewereheavilycontaminatedbypetroleum.Ofthe9samplesanalyzed,7hadtotalPACconcentrationsrangingfrom80mg/Kgto900mg/Kg,whiletheother2sampleshadconcentrationsof0.87and3.3mg/Kg,indicatingmoderatepetroleumcontamination.Allofthesesamplesexcepttheonecontaining0.87mg/KgtotalPAChadpositivebiomarkerfingerprintsconsistentwithoilcontaminationfoundelsewhereintheShushufindioilfield.
4.4.3LagoAgrioPetroleumcontaminationwasevidentinanalyzedsamplesofsoil,streamsediments,groundwatersandsurfacewatersfromtheLagoAgriosites(Table3).TheoverallpatternanddistributionofresultsissimilartothoseattheShushufindifield.
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Table3.Summaryofhydrocarbonanalysesforsamplescollectedduringspringandsummer2014fromLagoAgriooilfield,Ecuador.Analyticalresultsarepresentedasmg/Kgforsoilsandsedimentsandug/Lforwatersamples,allgivenwithtwosignificantfigures.
Site
TotalPAC
Totaln‐Alkanes TEM
TPHby8015B
WeatheringState27
DiagnosticBiomarkers28
Soils LA02‐SL022 0.98 1.9 130 44 5 LA02‐SL023 35 18 2,800 6 LA02‐SL024 1.2 18 130 6 LA16‐SL001 130 18 7,600 2,400 5 YLA16‐SL002 0.16 2.7 1,800 15 NA LA16‐SL003 0.16 1.2 300 8 NA Y?LA16‐SL004 (1)29 9.1 7.9 520 280 5 YLA16‐SL005 0.072 1.1 130 14 NA LA16‐SL006 0.069 0.12 590 10 NA LA16‐SL007 23 2,500 710 5 YLA16‐SL008 0.22 0.66 91 12 NA LA16‐SL009 0.63 1.3 220 55 5 Y?LA16‐SL010 0.86 2.4 200 37 5 Y?LA16‐SL011 (2) 0.91 1.4 320 41 5 Y?LA16‐SL012 0.95 4.0 92 75 6 LA16‐SL014 (2) 260 90 Y?LA16‐SL015 (1) 9.7 5 Sediments LA35‐SE001 270 456 88,000 5,200 5 YLA35‐SE002 600 71 29,000 6,500 5 YLA35‐SE003 36 19 14,000 5,400 6 YLA35‐SE004 4.5 5.8 9,000 570 6 YLA35‐SE005 2.4 6.9 44,000 320 7 Y Groundwater LA16‐GW001 66 7.3 1,100 5 LA16‐GW002 0.32 15 78 NA LA16‐GW003 0.24 2.8 130 NA LA16‐GW005 0.30 2.4 72 NA LA02‐GW007 2.1 6.5 290 6 LA02‐GW008 3.8 1.9 110 5 LA02‐GW009 (3) 42 6.1 91 5
27WeatheringstateisbasedonKaplan&Galperin199628Diagnosticbiomarkersymbols“Y”indicatesadefinitepetroleumbiomarkerfingerprintconsistentwiththepatternpresentedinTable1above;“Y?“indicatesabiomarkerfingerprintindicativeofpetroleumbutwiththeleastabundantbiomarkercompoundsnotdetected.29Numbersinparenthesesfollowingthesiteidentificationlabelsincolumn1indicatefieldduplicatesamples.
19
Site
TotalPAC
Totaln‐Alkanes TEM
TPHby8015B
WeatheringState27
DiagnosticBiomarkers28
LA02‐GW010 200 32 2,000 5 LA02‐GW011 0.070 2.1 61 NA LA02‐GW012 (3) 42 6.0 780 5 Surface Water LA35‐SW002 0.82 4.3 67 5 LA35‐SW003 (4) 0.49 3.8 82 NA LA35‐SW004 2.2 17 55 5 LA35‐SW005 1.86 2.3 2,700 6 LA35‐SW006 (4) 0.72 1.8 190 6
4.4.3.1LA‐02Thissitewasmoreextensivelyanalyzedin2013andmyoverallconclusionsasrelatetothissiteareincludedinmyDecember2013Report.Imaintainthoseconclusions.Limitedsamplingwasconductedin2014atthissitewhichIdiscussbelow.Twoofthe3soilsamplesanalyzedforPACfromLA‐02hadlowbutclearlevelsofpetroleumcontamination,withtotalPACconcentrationsof0.98and1.2mg/Kg.Petroleumcontaminationinthethirdsampleanalyzedwasheavy,withtheconcentrationoftotalPACat35mg/Kg.Biomarkerswerenotanalyzedinthissamplebecauseofinsufficientsamplemasscollectedforalltheanalysestobeperformed.PetroleumcontaminationofgroundwateratLA‐02wasalsoclearlyevident.While1samplecontainedabackgroundconcentrationoftotalPACat0.070ug/L,concentrationsintheother5samplesrangedfrom2.1ug/Lto200ug/L,and3ofthe5sampleshadconcentrationsabove40ug/L.Elevatedconcentrationsofpristaneandphytaneindicatethiscontaminationwasmainlypresentaswhole,free‐phaseoil.Thehydrocarbonsdetectedinthese5samplesweresufficientlyabundantthatweatheringstatescouldbeassigned,allofwhichwere5.
4.4.3.2LA‐16Fourofthe13soilsamplesanalyzedforPACfromLA‐16hadmoderateorheavylevelsofpetroleumcontamination.ThehighesttotalPACconcentrationwas130mg/Kg,followedby23mg/Kginanothersampleandconcentrationsabove9mg/Kgintheremainingtwo.Another5soilsampleshadlowbutclearpetroleumcontamination,withtotalPACconcentrationsrangingfrom0.63–0.95mg/Kg.Petroleuminmostofthesesampleswasconfirmedbybiomarkerfingerprints.Theremaining4sampleshadtotalPACconcentrationsnearoratthenaturalbackground,rangingfrom0.069–0.16mg/Kg.
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Ofthe4groundwatersamplesanalyzedforPAC,onewasheavilycontaminatedbypetroleum,withatotalPACconcentrationof66ug/Lataweatheringstateof5.Concentrationsintheother3samplesrangedfrom0.24–0.32ug/L,andconsistedofPACdistributionsdepictedinFig.3asindicativeoflow‐levelpetroleumcontamination.
4.4.3.3LA‐35OnlystreamsedimentandsurfacewatersampleswereanalyzedforPACfromLA‐35.Ofthe5streamsedimentsamples,thehighestconcentrationoftotalPACwas600mg/Kg,followedbyanothersamplecontaining270mg/Kg.Athirdsamplecontainedabout36mg/Kg,allindicatingheavypetroleumcontamination.Theremainingtwosamplescontained2.4and4.5mg/Kg,indicatingmodestpetroleumcontamination.Petroleumcontaminationinallthesesampleswasconfirmedbythebiomarkerfingerprints,andtheweatheringstatesrangedfrom5to7,thelatterindicatingveryweatheredoil.All5ofthesurfacewatersamplesanalyzedforPACcontainedelevatedconcentrationsindicativeofpetroleumcontamination,rangingfrom0.49ug/Lto2.2ug/L.
4.4.4AguaricoAswiththesamplesfromLagoAgrio,samplesfromtheAguaricooilfieldsitesreflectthegeneralpatternofpetroleumcontaminationintheregion(Table4).Table4.Summaryofhydrocarbonanalysesforsamplescollectedduringspringandsummer2014fromAguaricooilfield,Ecuador.Analyticalresultsarepresentedasmg/Kgforsoilsandsedimentsandug/Lforwatersamples,allgivenwithtwosignificantfigures.
Site
TotalPAH
Totaln‐Alkanes TEM
TPHby8015B
WeatheringState30
DiagnosticBiomarkers31
Soils AG04‐SL001 3285 1362 690,000 120,000 5 YAG04‐SL002 2894 1137 590,000 120,000 5 YAG06‐SL001 7.7 5.7 890 230 5 Y?AG06‐SL002 0.18 1.9 150 18 NA Y?AG06‐SL003 0.15 1.2 2,100 16 NA Y?AG06‐SL004 0.35 7.8 300 26 NA Y?AG06‐SL005 12 12 3,600 360 5 Y
30WeatheringstateisbasedonKaplan&Galperin199631Diagnosticbiomarkersymbols“Y”indicatesadefinitepetroleumbiomarkerfingerprintconsistentwiththepatternpresentedinTable1above;“Y?“indicatesabiomarkerfingerprintindicativeofpetroleumbutwiththeleastabundantbiomarkercompoundsnotdetected.
21
Site
TotalPAH
Totaln‐Alkanes TEM
TPHby8015B
WeatheringState30
DiagnosticBiomarkers31
AG06‐SL006 31 11 2,000 580 5 YAG06‐SL007 13 6.7 2,500 390 5 YAG06‐SL008 126 14,000 2,300 5 YAG06‐SL009 75 20 6,800 1,600 5 Y Sediments AG06‐SE001 0.52 29 1,000 66 7 AG06‐SE002 2.1 2.7 2,200 100 6 YAG06‐SE003 0.59 4.2 1,900 34 5 YAG06‐SE004 0.33 11 780 34 NA YAG06‐SE005 0.63 5.8 740 31 7 Y Groundwater AG06‐GW005 5.5 6.6 130 5 AG06‐GW007 0.60 4.5 220 5 AG06‐GW008 26 10 2,800 5 AG06‐GW009 3.2 21 320 5 AG06‐GW010 214 86 3,500 5 AG06‐GW011 7.2 13 490 5 Surface Water AG06‐SW001 0.091 1.0 42 NA AG06‐SW002 0.078 9.7 39 NA AG06‐SW003 0.10 0.51 40 NA AG06‐SW004 0.094 0.48 40 NA AG06‐SW005 0.089 0.85 50 NA
4.4.4.1AG‐04Only2samples,bothofheavilycontaminatedsoils,werecollectedfromtheAG‐04site.Bothwereheavilycontaminatedbypetroleum,withconcentrationsoftotalPACof2,900and3,300mg/Kg.TheassociatedTEMconcentrationsof590,000–690,000mg/Kgimplysamplesconsistingofmoreoilthaninorganics(i.e.59%‐69%oil).Thebiomarkerfingerprintscorroboratethepetroleumsource.
4.4.4.2AG‐06ConcentrationsoftotalPACinthe9soilsamplesanalyzedfromAG‐06rangedfromnearbackgroundconcentrations(3samplesrangingfrom0.15to0.35mg/KgtotalPAC)toheavilycontaminatedbypetroleum.ThehighesttotalPACconcentrationatAG‐06was130mg/Kg,with5othersamplesrangingfrom7.8–75mg/Kg.Allofthesesampleshadbiomarkerfingerprintsindicativeofoil,andthe5mostcontaminatedsampleshadweatheringstatesof5.FivesamplesofstreamsedimentswerecollectedandanalyzedforPAC,andhadconcentrationsoftotalPACrangingfrom0.33–2.1ug/L.ThePACdistribution
22
indicatesapetroleumsource,confirmedbythebiomarkerfingerprintin4ofthesamples.Theweatheringstatesofthesesamplesrangedfrom5–7,againconsistentwiththepatternofmoreadvancedweatheringinoil‐contaminatedstreamsedimentsthaninsoils.SixgroundwatersampleshadconcentrationsoftotalPACashighas210ug/L.Anothersamplecontained26ug/L,andthreemoresamplescontainedfrom3.2–7.2ug/LThelowestconcentrationfoundwas0.60ug/L.Alloftheseconcentrationsareclearlyabovethenaturalbackground,andthePACdistributionindicatesapetroleumsource.Theweatheringstatesoftheoilinthesesampleswereall5.Finally,5surfacewatersampleswerecollectedandanalyzedforPAC.ConcentrationsoftotalPACrangedfrom0.078–0.11ug/L,withabundancedistributionsreflectingmainlythenaturalbackgrounddistributionofPACdepictedinFig.3.4.5.ResponsetoHincheeMemorialofMay2014InhisMay2014ReplyMemorial,HincheeraisedobjectionstothreeofthepointsImadeinmyDecember2013RejoinderReport.32ThefirstobjectioniswithregardtotheappropriatenessoftheToxicityCharacteristicLeachingProcedure(TCLP)foruseinconjunctionwiththeRAPremediation.ThesecondiswithregardtomycriticismofHinchee’sandConnor’smethodtodeterminetheextentofoilweathering.Thethirdiswithregardtomycharacterizationofoilweatheringandevidencefortherateofweatheringofoil‐contaminatedsoilsandsedimentsintheformerConcessionArea.IfindallthreeofDr.Hinchee’sobjectionswithoutmerit,andIstandbythepositionsIstatedinearlierreports.MyresponsestoDr.Hinchee’sobjectionsfollow,intheorderpresentedabove.4.5.1AppropriatenessoftheToxicityCharacteristicLeachingProcedureInmyDecember2013RejoinderReport33Inotedthatitisinprinciplenotpossibleforanycombinationofoilcomponentstoreachtheregulatorythresholdconcentrationof1000mg/L(oreven200mg/L)throughdissolutionalone.Consequently,Iconcludedthattoreachthisthreshold,soilsorsedimentswouldhavetobesaturatedwithoil,allowingtheoiltodrainoutofsoilsorsedimentsasaseparateorganicphase.Inhisobjection,Dr.Hincheeassertsthatthiswasactuallytheintentionofthetest34,thatis,todeterminewhethertheoilwassufficientlymobileinsoilsorsedimentstomoveasaseparatephaseunderapplicationofpressure.Butthisassertionisbelied
32Short2013RejoinderReport33Ibid.,p.2334HincheeMay2014ResponseReport,p.6
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bytheinstructionsgivenbytheEPAforthistest,35whichstatethatwhenmultiphasicsamples(i.e.samplesthatconsistofanoilphaseandasolidinorganicphasesuchasoiledsoilorsedimentsamples)areinvolved,theliquidphasemustfirstbeseparatedfromthesolidphase,priortoadditionoftheacidifiedaqueousphaseandsubsequentmixing,followedbyasecondfiltrationsteptoseparatetheaddedwaterfromthesolids.ThisisnothowthetestswereactuallyconductedfortheRAP.36Instead,theacidifiedwaterwasaddedimmediatelybeforeevaluatingwhetheroilcouldflowoutofthesoilorsedimentsample.Theadditionofacidifiedwateratthestartoftheprocedureimpairedtheabilityoftheoiltoflowthroughthefiltrationdevice,anissuenotedinourinitialFebruary2013report.374.5.2ConsequencesoftheFlawedOilWeatheringMethodusedbyDrs.HincheeandConnorDr.HincheeclaimsthatthemostimportantconsequenceoftheflawsIpointedoutintheO’ReillyandThorsenmethod38fordeterminingtheextentofoilweatheringistheeffectithasonthesolubilityofoilcomponents.39Ihaveneverdisputedthatoilcompositionchangesresultingfromdifferentiallossesofsomecomponentsduringweatheringdoaffecttheeffectivesolubilityofthecomponentsremainingintheoil.ButIdonotbelievethatisthemostimportantconsequenceoftheflawedO’ReillyandThorsenmethodfordeterminingoilweathering.BothDr.HincheeandMr.ConnorreliedontheflawedO’ReillyandThorsenmethodtosupporttheirclaimthattheoverwhelmingmajorityofoilremainingincontaminatedsoilsandsedimentsissoweatheredthatithasbecomeanimmobilehardenedsolid.Byshowinghowthisclaimisseriouslyflawed,Iraisethelikelihoodthatcontaminatingoilsthatremainintheregion’ssoilsandsedimentscouldflowthroughthem.Ifsomeoftheremainingoilisstillsufficientlyfluidtobecarriedbywaterthroughflowchannelsinsubsurfaceclays,amechanismfortransportingfree‐phaseweatheredcrudeoilfrominsidetooutsideun‐linedpitsbecomesplausible.LouisBergerhasobservedsiteswherethistransportationmechanismseemslikelyandmyanalysisshowsthatitisnotprecludedasDr.HincheeandMr.Connorbelieve.ThisisamuchmoreseriousconsequenceofthemistakeninferencesbasedontheflawedO’ReillyandThorsenmethod.4.5.3CharacterizationofWeatheringRatesforCrudeOilRemaininginConcessionAreaSoilsandSediments35USEPAMethod1311,July1992,p.1136LouisBerger,2013,p.5237Ibid.,p.5438O’Reilly,K.andThorsen,W.,2010,ImpactofCrudeOilWeatheringontheCalculatedEffectiveSolubilityofAromaticCompounds:EvaluationofSoilsfromEcuadoreanOilFields,SoilandSedimentContamination,19:391–40439HincheeMay2014ResponseReport,p.10
24
Dr.HincheeclaimsthatthemethodIreliedonfordeterminingtheweatheringstateofoilintheformerConcessionAreaisqualitativeandquestionable,andinanycasemyapplicationofthismethodtosamplescollectedin2013byLouisBergerincomparisonwithsamplescollectedearlierandsummarizedbyChevronexpertDr.Douglasdonotsupportmyconclusionregardingweatheringrates,inaccuratelyportrayedbyDr.Hincheeas“arrestedbiodegradation”.Irejecttheseclaimsonthebasisofthefollowingthreeobservations:1.Dr.HincheestatesthatIclaimedthat“...hydrocarbonsintheformerConcessionareaareinastateofarrestedbiodegradation...”40.WhatIactuallysaidwasthathydrocarbonsareinastateoflargelyarrestedbiodegradation41–acruciallyimportantdifference.Underconditionsoflowoxygenandhighoilconcentrationinsoilsorsediments,biodegradationratesmaybeordersofmagnitudeslowerthanwhenoilisspreadoutasthinlayersorsmalldropletsatthesoilsurface.Astateoflargelyarrestedbiodegradationdoesnotmeanthatbiodegradationhasstopped,butinsteadthatitissoslowthatoilmaypersist,largelyunchanged,fordecadesorlonger.2.ThemethodIreliedontodetermineoilweatheringstatesispresentedinKaplanandGalperin,42whichisexactlythesamemethodusedbyChevronexpertDr.GregoryDouglastocharacterizetheweatheringstatesofhundredsofoiledsoilandsedimentsamples.43IusedthismethodinparttoavoidthesortofobjectionraisedherebyDr.Hinchee,reasoningthatadoptingthemethodusedbyChevron’sexpertswouldbeviewedasreasonable.InanycaseIviewthequalitativebasisofthemethodasastrengthratherthanaweakness,becauseitrecognizestheregularsequenceofcompositionchangesasoilproductsweatherintheenvironment,andhenceisnotvulnerabletoquantitativedisputesthatarisewhendifferentanalyticalmethodsareapplied.Forexample,completelossofallthenormalalkanesfromcrudeoilbyweatheringisunmistakable,regardlessofthesubtledifferencesinthegaschromatographicorothermethodsusedtomeasurethem.3.Finally,Dr.Hincheeassertsthatcomparisonofresultsfordeterminingweatheringratesshould(ideally)befromthesamelocationsanddepths44,butthenproceedstoignorehisownadvicetoarriveatunjustifiedconclusionsregardingweatheringrates.Samplescollectedfromthesamelocationsanddepthsatthebeginningandagainattheendofatimeintervalofsufficientdurationforreliabledetectionofweatheringarenotavailable.Intheirabsence,weatheringchangesmightbeinferredfromaveragedweatheringstatesofarepresentativesetof40HincheeMay2014ResponseReport,p.1241LouisBerger,2013,p.6142KaplanandGalperin,199643SummaryofForensicAnalysesofCrudeOilWeatheringfrom45JudicialInspections,August2004–November2006,Chevron,OrienteRegion,Ecuador.GSIEnvironmental,Inc.,2211Norfolk,Suite1000,Texas77098‐4054,May17,200744HincheeMay2014ResponseReport,p.12
25
samples.Unfortunately,neitherthesamplescollectedfortheJudicialInspectionsbyChevroninthemid‐2000’s,northesamplescollectedbyLouisBergerin2013,canbetakenasrepresentativeinthissenseoftheenvironmentsampled,becauseneithersamplingprogramincludedarandomselectioncomponenttothesamplingselectionprocess.WhenChevronclaimstheirsamplingwas“representative”45,theyareusingthetermlooselyasasynonymfor“typical”or“indicative”ofresultsthatmaybeexpectedatorverynearthepreciselocationsampled,andnotinthestrictscientificsenseoftheterm“representative”.Scientifically,“representativesampling”indicatesthesamplinglocationswereselectedinamannersuchthateverypossiblesamplinglocationwithinthearearepresentedhasanequalchanceofactuallybeingsampled.Samplinginthis“equal‐probability”manneristheonlywaytoguaranteethattheresultsofthesamplingtrulyrepresenttheentireareasampled.Neithersamplingin“typical”areas,noreven“haphazard”sampling,canbetakenastruly“representative”inthissense.ThesamplingconductedbyLouisBergerin2013andin2014wasalsonottruly“representative”inthestrictscientificsenseofthisterm,norhasitmadeouttobeso.Instead,theLouisBergersamplingwasconductedtoevaluateotherspecificquestionssuchastheplausibilityofpetroleummigrationpathwaysfromtheinsidetotheoutsideofoiledpitsandbeyond.Suchtargetedsampling,tailoredforspecificpurposesthatareexplicitlystatedinadvance,isperfectlylegitimate,aswasacknowledgedbyChevronexpertDr.RobertHinchee46.Butthiskindoftargetedsamplingstillcannotbetakenas“representative”ofthebroadareawheresamplingoccurred,andespeciallynotforquantitativecomparisonsonwhichcomputationsofpetroleumweatheringratesarebased.Forexample,samplingresultsindicatethatresidualpetroleuminstreamsedimentsisgenerallymoreweatheredthanpetroleumburiedinsoils.Hence,ifsamplingoneyearincludesasubstantiallysmallerproportionofstreamsedimentsincomparisontoasucceedingyear,thenthechangeintheaverageweatheringbetweenthesetwoyearsmaysimplyreflectthedifferencesintheproportionsofsedimentandsoilsamplesbetweenthetwoyears,insteadofactualdifferencesinweathering.WhenDr.HincheecomparesresultsfromChevron’sJudicialInspections(JI)duringthemid‐2000’swiththe2013LouisBergersamplestoconcludethattheaverageKaplan&Galperinweatheringindexincreasedfrom4.6into6.1,hepresumesimplicitlythatbothsamplingprogramsweretrulyrepresentativeinthestrictscientificsense,andhesimplyignoresahostofplausiblealternativeexplanationsfortheseresults.Thesealternativeexplanationsareplausiblebecausethesampling45ExpertOpinionofJohnA.Connor,P.E.,P.G.,B.C.E.E.RegardingRemediationActivitiesandEnvironmentalConditionsintheFormerPetroecuador–TexacoConcession,OrienteRegion,Ecuador,ResponsetoLBGReportofFebruary2013,Issued3June2013,p.1246HincheeMay2014ResponseReport,p.12
26
wasinfactnottrulyrepresentative,andsotheresultscomparedmayreflectprimarilydifferencesintheproportionsofstreamsediments,ofsurfaceoilsamples(whichalsotendtobemoreweatheredthanburiedoil)andofoilburiedinsoilsbetweenthesamplesetscollectedforthemid‐2000’sJIsamplingandthe2013LouisBergersampling,ratherthantheactualprogressofoilweatheringduringtheinterveningtimeinterval.Consequently,Dr.Hinchee’scomparisonofaverageweatheringstatesfromthetwosamplingprogramstomakeinferenceswithregardtothestatisticalsignificanceoftheirdifferencesrestsontheclearlyunjustifiableassumptionthatthesesamplesarerepresentative,inflagrantdisregardforfundamentalprinciplesofscientificinference.InmyDecember2013RejoinderReport47InotedthattherangesofweatheringstatesfromChevron’sandLouisBerger’ssamplingprogramsbroadlyoverlap,suggestingthatlittleweatheringhadoccurredduringthenearly10yearsbetweenthem.Thisinitselfisaremarkabletestamenttotheslowrateofweathering.ButIdidnotinfermorebroadlybecauseanysuchinferencesarelimitedbythewaythatsamplingwasconductedforboththeChevronandtheLouisBergersamplingcampaigns.4.6.ComparisonofEcuadorOrienteCrudeOilwithBunkerOilSpilledfromthePrestigeOilSpillConsiderableresearchhasbeendoneonthetoxicologicaleffectsofotheroilspills,especiallythePrestigeoilspillofftheSpanishcoastin2002.TocomparethisresearchwithconditionsintheOrienterequiresestablishingthattheoilsinvolvedshareatleastabroadlysimilarsuiteoftoxiccompounds.TheproductreleasedinthePrestigeoilspillwasnumber6fueloil,alsoknownasBunkeroil,aheavyoilconsistingmainlyofresidualhydrocarbons,resinsandasphaltenesthatremainafterdistillationoflightercomponentsduringthepetroleumrefiningprocess.Althoughremovaloftheselightercomponentsalterstheconcentrationsofthecompoundsthatremaininthenumber6fueloil,theabundancedistributionofPAHs,usuallyconsideredthemostpersistentclassoftoxiccompoundsinpetroleum,isbroadlysimilartothatoftheoriginalpetroleum.ThedistributionofPACsinthenumber6fueloilreleasedfromthePrestigeispresentedinFigure4,alongwiththecomparabledistributioninShushufindicrudeoil.NotethatbothcontainthesametypesofPACsingenerallysimilarproportions,althoughconcentrationsofsomeofthePACsinthePrestigeoilaresubstantiallygreaterthantheircounterpartsinShushufindicrudeoil.However,asShushufindicrudeoilweatherstheseconcentrationswilltendtoconverge,becauselossesofthelighterpetroleumcomponentsduringweatheringmimicstoanextentthedistillationprocessinarefinery.TheresultisthatafterevenmodestweatheringthetoxicityoftheShushufindicrudeoilcausedbyPACswouldbebroadlycomparablewiththatofthePrestigeoil.47Short2013RejoinderReport
27
Figure4.ConcentrationsofpolycyclicaromaticcompoundsinNo.6fueloilreleasedbytheT/VPrestige(bluebars)48andinun‐weatheredShushufindicrudeoil49(redbars).BF=benzofluoranthenes;seeFig.3legendforotherabbreviations.
48AlzagaA.,MontuoriP,OrtizL,BayonaJM,AlbaigésJ(2004)Fastsolid‐phaseextraction‐gaschromatography‐massspectrometryprocedureforoilfingerprintingApplicationtothePrestigeoilspill.JournalofChromatographyA1025:133‐13849GSD305171
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