EPA-3015a-(microwave-digestion-of-water)

3015A-1Revision1February2007METHOD3015AMICROWAVEASSISTEDACIDDIGESTIONOFAQUEOUSSAMPLESANDEXTRACTSSW-846isnotintendedtobeananalyticaltrainingmanual.Therefore,methodproceduresarewrittenbasedontheassumptionthattheywillbeperformedbyanalystswhoareformallytrainedinatleastthebasicprinciplesofchemicalanalysisandintheuseofthesubjecttechnology.Inaddition,SW-846methods,withtheexceptionofrequiredmethodusefortheanalysisofmethod-definedparameters,areintendedtobeguidancemethodswhichcontaingeneralinformationonhowtoperformananalyticalprocedureortechniquewhichalaboratorycanuseasabasicstartingpointforgeneratingitsowndetailedStandardOperatingProcedure(SOP),eitherforitsowngeneraluseorforaspecificprojectapplication.Theperformancedataincludedinthismethodareforguidancepurposesonly,andarenotintendedtobeandmustnotbeusedasabsoluteQCacceptancecriteriaforpurposesoflaboratoryaccreditation.1.0SCOPEANDAPPLICATION1.1Thismicrowavemethodisdesignedtoperformextractionusingmicrowaveheatingwithnitricacid(HNO3),oralternatively,nitricacidandhydrochloricacid(HCl).Sincethismethodisnotintendedtoaccomplishtotaldecompositionofthesample,theextractedanalyteconcentrationsmaynotreflectthetotalcontentinthesample.Thismethodisapplicabletothemicrowave-assistedacidextraction/dissolutionofavailablemetalsinaqueoussamples,drinkingwater,mobility-procedureextracts,andwastesthatcontainsuspendedsolidsforthefollowingelements:ElementCASRegistryNo.a*Aluminum(Al)7429-90-5*Antimony(Sb)7440-36-0Arsenic(As)7440-38-2*Barium(Ba)7440-39-3*Beryllium(Be)7440-41-7Boron(B)7440-42-8Cadmium(Cd)7440-43-9Calcium(Ca)7440-70-2*Chromium(Cr)7440-47-3Cobalt(Co)7440-48-4Copper(Cu)7440-50-8*Iron(Fe)7439-89-6ElementCASRegistryNo.a3015A-2Revision1February2007Lead(Pb)7439-92-1*Magnesium(Mg)7439-95-4Manganese(Mn)7439-96-5Mercury(Hg)7439-97-6Molybdenum(Mo)7439-98-7Nickel(Ni)7440-02-0Potassium(K)7440-09-7Selenium(Se)7782-49-2*Silver(Ag)7440-22-4Sodium(Na)7440-23-5Strontium(Sr)7440-24-6Thallium(Tl)7440-28-0*Vanadium(V)7440-62-2Zinc(Zn)7440-66-6aChemicalAbstractServiceRegistryNumber*ElementswhichtypicallyrequiretheadditionofHClforoptimumrecoveries.Otherelementsandmatricesmaybeanalyzedbythismethodifperformanceisdemonstratedfortheanalyteofinterest,inthematricesofinterest,attheconcentrationlevelsofinterest(seeSec.9.0).1.2Thismethodprovidesoptionsforimprovingtheperformanceforcertainanalytes,suchasantimony,iron,aluminum,andsilverbytheadditionofhydrochloricacid,whennecessary.Itisintendedtoprovidearapidmulti-elementacidextractionpriortoanalysissothatdecisionscanbemadeaboutmaterialsandsiteclean-uplevels,andasanestimateofmetaltoxicity.Digestsproducedbythemethodaresuitableforanalysisbyinductivelycoupledplasmamassspectrometry(ICP-MS),inductivelycoupledplasmaatomicemissionspectrometry(ICP-AES),flameatomicabsorptionspectrophotometry(FLAA),andgraphitefurnaceatomicabsorptionspectrophotometry(GFAA).However,theadditionofHClmaylimitthequantitationmethods,orincreasethedifficultiesofquantitationwithsometechniques.Duetotherapidadvancesinmicrowavetechnology,consultthemanufacturer'srecommendedinstructionsforguidanceontheirmicrowavedigestionsystem.Thismethodisgenericandmaybeimplementedusingawidevarietyoflaboratorymicrowaveequipment.1.3Priortoemployingthismethod,analystsareadvisedtoconsultthedeterminativemethodthatmaybeemployedintheoverallanalysisforadditionalinformationonqualitycontrolprocedures,developmentofQCacceptancecriteria,calculations,andgeneralguidance.AnalystsalsoshouldconsultthedisclaimerstatementatthefrontofthemanualandtheinformationinChapterTwoforguidanceontheintendedflexibilityinthechoiceofmethods,apparatus,materials,reagents,andsupplies,andontheresponsibilitiesoftheanalystfor3015A-3Revision1February2007demonstratingthatthetechniquesemployedareappropriatefortheanalytesofinterest,inthematrixofinterest,andatthelevelsofconcern.Inaddition,analystsanddatausersareadvisedthat,exceptwhereexplicitlyspecifiedinaregulation,theuseofSW-846methodsisnotmandatoryinresponsetoFederaltestingrequirements.TheinformationcontainedinthismethodisprovidedbyEPAasguidancetobeusedbytheanalystandtheregulatedcommunityinmakingjudgmentsnecessarytogenerateresultsthatmeetthedataqualityobjectivesfortheintendedapplication.1.4Useofthismethodisrestrictedtouseby,orundersupervisionof,properlyexperiencedandtrainedpersonnel.Eachanalystmustdemonstratetheabilitytogenerateacceptableresultswiththismethod.2.0SUMMARYOFMETHODArepresentativeaqueoussampleisextractedwithconcentratednitricacidor,optionally,concentratednitricacidandconcentratedhydrochloricacid,usingmicrowaveheatingwithasuitablelaboratorymicrowaveunit.Thesampleandacid(s)areplacedinafluorocarbonpolymer(suchasPFAorTFM)orquartzmicrowavevesselorvesselliner.Thevesselissealedandheatedinthemicrowaveunitforaspecifiedperiodoftime.Aftercooling,thevesselcontentsarefiltered,centrifuged,orallowedtosettleandthendilutedtovolumeandanalyzedbytheappropriatedeterminativemethod.3.0DEFINITIONSRefertoChapterOne,ChapterThree,andthemanufacturer'sinstructionsfordefinitionsthatmayberelevanttothisprocedure.4.0INTERFERENCES4.1S