Designation:E2856−13StandardGuideforEstimationofLNAPLTransmissivity1ThisstandardisissuedunderthefixeddesignationE2856;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thisguideprovidesfielddatacollectionandcalculationmethodologiesfortheestimationoflightnon-aqueousphaseliquid(LNAPL)transmissivityinunconsolidatedporoussedi-ments.Themethodologiespresentedhereinmay,ormaynotbe,applicabletootherhydrogeologicregimes(forexample,karst,fractureflow).LNAPLtransmissivityrepresentsthevolumeofLNAPL(L3)throughaunitwidth(L)ofaquiferperunittime(t)perunitdrawdown(L)withunitsof(L2/T).LNAPLtransmissivityisadirectlyproportionalmetricforLNAPLrecoverabilitywhereasothermetricssuchasapparentLNAPLthicknessgaugedinwellsdonotexhibitaconsistentrelationshiptorecoverability.TherecoverabilityforagivengaugedLNAPLthicknessinawellwillvarybetweendifferentsoiltypes,LNAPLtypesorhydrogeologicconditions.LNAPLtransmissivityaccountsforthoseparametersandconditions.LNAPLtransmissivityvaluescanbeusedinthefollowingfiveways:(1)EstimateLNAPLrecoveryrateformultipletech-nologies;(2)Identifytrendsinrecoverabilityviamapping;(3)Appliedasaleading(startup)indicatorforrecovery;(4)Appliedasalagging(shutdown)indicatorforLNAPLrecov-ery;and(5)Appliedasarobustcalibrationmetricformulti-phasemodels(HawthorneandKirkman,2011(1)2andITRC((2)).ThemethodologiesforLNAPLtransmissivityestimationprovidedinthisdocumentincludeshort-termaquifertestingmethods(LNAPLbaildown/slugtestingandmanualLNAPLskimmingtesting),andlong-termmethods(thatis,LNAPLrecoverysystemperformanceanalysis,andLNAPLtracertesting).Themagnitudeoftransmissivityofanyfluidinthesubsurfaceiscontrolledbythesamevariables(thatis,fluidporespacesaturation,soilpermeability,fluiddensity,fluidviscosity,theintervalthatLNAPLflowsoverintheformationandthegravitationalacc...
