Designation:D3977−97(Reapproved2019)StandardTestMethodsforDeterminingSedimentConcentrationinWaterSamples1ThisstandardisissuedunderthefixeddesignationD3977;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thesetestmethodscoverthedeterminationofsedimentconcentrationsinwaterandwastewatersamplescollectedfromlakes,reservoirs,ponds,streams,andotherwaterbodies.Inlakesandotherquiescent-waterbodies,concentrationsofsedimentinsamplesarenearlyequaltoconcentrationsatsamplingpoints;inmostinstances,sampleconcentrationsarenotstronglyinfluencedbycollectiontechniques.Inriversandotherflowing-waterbodies,concentrationsofsedimentinsamplesdependuponthemannerinwhichthesamplesarecollected.Concentrationsinisokinetically-collectedsamplescanbemultipliedbywaterdischargestoobtainsedimentdischargesinthevicinityofthesamplingpoints.1.2TheproceduresgiveninthesetestmethodsareusedbytheAgriculturalResearchService,GeologicalSurvey,NationalResourcesConservationService,BureauofReclamation,andotheragenciesresponsibleforstudyingwaterbodies.Thesetestmethodsareadaptedfromalaboratory-proceduremanual2andaquality-assuranceplan.31.3Thesetestmethodsinclude:SectionsTestMethodA—Evaporation8to13TestMethodB—Filtration14to19TestMethodC—Wet-Sieving-Filtration20to251.4TestMethodAcanbeusedonlyonsedimentsthatsettlewithintheallottedstoragetimeofthesampleswhichusuallyrangesfromafewdaystoafewweeks.Acorrectionfactormustbeappliedifdissolved-solidsconcentrationexceedsabout10%ofthesedimentconcentration.1.5TestMethodBcanbeusedonlyonsamplescontainingsandconcentrationslessthanabout10000ppmandclayconcentrationslessthanabout200ppm.Thesedimentneednotbesettleablebecausefiltersareusedtoseparatewaterfromthesediment.Correctionfactorsfordissolvedsolidsarenotrequired.1.6TestMethodCcanbeusediftwoconcentrationvaluesarereq...
