Designation:D5611−94(Reapproved2016)StandardGuideforConductingaSensitivityAnalysisforaGroundwaterFlowModelApplication1ThisstandardisissuedunderthefixeddesignationD5611;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thisguidecoverstechniquesthatshouldbeusedtoconductasensitivityanalysisforagroundwaterflowmodel.Thesensitivityanalysisresultsinquantitativerelationshipsbetweenmodelresultsandtheinputhydraulicpropertiesorboundaryconditionsoftheaquifers.1.2Afteragroundwaterflowmodelhasbeencalibrated,asensitivityanalysismaybeperformed.Examinationofthesensitivityofcalibrationresidualsandmodelconclusionstomodelinputsisamethodforassessingtheadequacyofthemodelwithrespecttoitsintendedfunction.1.3Afteramodelhasbeencalibrated,amodelermayvarythevalueofsomeaspectoftheconditionsapplyingsolelytothepredictionsimulationsinordertosatisfysomedesigncriteria.Forexample,thenumberandlocationsofproposedpumpingwellsmaybevariedinordertominimizetherequireddischarge.Insofarastheseaspectsarecontrollable,variationoftheseparametersispartofanoptimizationprocedure,and,forthepurposesofthisguide,wouldnotbeconsideredtobeasensitivityanalysis.Ontheotherhand,estimatesoffutureconditionsthatarenotcontrollable,suchastherechargeduringapostulateddroughtofunknowndurationandseverity,wouldbeconsideredascandidatesforasensitivityanalysis.1.4Thisguidepresentsthesimplestacceptabletechniquesforconductingasensitivityanalysis.Othertechniqueshavebeendevelopedbyresearchersandcouldbeusedinlieuofthetechniquesinthisguide.1.5Thisguideiswrittenforperformingsensitivityanalysesforgroundwaterflowmodels.However,thesetechniquescouldbeappliedtoothertypesofgroundwaterrelatedmodels,suchasanalyticalmodels,multi-phaseflowmodels,non-continuum(karstorfractureflow)models,ormasstransportmodels.1.6Thisguideisoneofaseriesongrou...
