Designation:C1308−08(Reapproved2017)StandardTestMethodforAcceleratedLeachTestforDiffusiveReleasesfromSolidifiedWasteandaComputerProgramtoModelDiffusive,FractionalLeachingfromCylindricalWasteForms1ThisstandardisissuedunderthefixeddesignationC1308;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodprovidesproceduresformeasuringtheleachratesofelementsfromasolidifiedmatrixmaterial,determiningifthereleasesarecontrolledbymassdiffusion,computingvaluesofdiffusionconstantsbasedonmodels,andverifyingprojectedlong-termdiffusivereleases.Thistestmethodisapplicabletoanymaterialthatdoesnotdegradeordeformduringthetest.1.1.1Ifmassdiffusionisthedominantstepintheleachingmechanism,thentheresultsofthistestcanbeusedtocalculatediffusioncoefficientsusingmathematicaldiffusionmodels.Acomputerprogramdevelopedforthatpurposeisavailableasacompaniontothistestmethod(Note1).1.1.2Itshouldbeverifiedthatleachingiscontrolledbydiffusionbyameansotherthananalysisoftheleachtestsolutiondata.Analysisofconcentrationprofilesofspeciesofinterestnearthesurfaceofthesolidwasteformafterthetestisrecommendedforthispurpose.1.1.3Potentialeffectsofpartitioningonthetestresultscanbeidentifiedthroughmodeling,althoughfurthertestingandanalysesarerequiredtodeterminethecauseofpartitioning(forexample,ifitoccursduringproductionofthematerialorasaresultofleaching).1.2Themethodisamodificationofothersemi-dynamictestssuchastheIAEAtest(1)2andtheANS16.1LeachTestwhereinelevatedtemperaturesareusedtoacceleratediffusivereleasetoanextentthatwouldonlybereachedafterverylongtimesatlowertemperatures.Thisapproachprovidesamecha-nisticbasisforcalculatingdiffusivereleasesatrepository-relevanttemperaturesoverlongtimes,providedthattheleachingmechanismdoesnotchangewithtemperature.1.2.1Testscanbeconductedatelevatedtemperatur...
