Designation:D5850−20StandardPracticefor(AnalyticalProcedure)DeterminingTransmissivity,StorageCoefficient,andAnisotropyRatiofromaNetworkofPartiallyPenetratingWells1ThisstandardisissuedunderthefixeddesignationD5850;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thispracticecoversananalyticalprocedurefordeter-miningthetransmissivity,storagecoefficient,andratioofverticaltohorizontalhydraulicconductivityofaconfinedaquiferusingobservationwelldrawdownmeasurementsfromaconstant-ratepumpingtest.Thispracticeusesdatafromaminimumoffourpartiallypenetrating,recommendedtobepositionedobservationwellsaroundapartiallypenetratingcontrolwell.1.2TheanalyticalprocedureisusedinconjunctionwiththefieldprocedureinTestMethodD4050.1.3Limitations—Thelimitationsofthetechniquefordeter-minationofthehorizontalandverticalhydraulicconductivityofaquifersareprimarilyrelatedtothecorrespondencebetweenthefieldsituationandthesimplifyingassumptionofthispractice.1.4Units—Thevaluesstatedininch-poundunitsaretoberegardedasthestandard.TheSIunitsgiveninparenthesesaremathematicalconversions,whichareprovidedforinformationpurposesonlyandarenotconsideredstandard.Thereportingofresultsinunitsotherthaninch-poundshallnotberegardedasnonconformancewiththisstandard.1.5AllobservedandcalculatedvaluesshallconformtotheguidelinesforsignificantdigitsandroundingestablishedinPracticeD6026,unlesssupersededbythisstandard.1.6Theproceduresusedtospecifyhowdataarecollected/recordedorcalculatedinthisstandardareregardedastheindustrystandard.Inaddition,theyarerepresentativeofthesignificantdigitsthatgenerallyshouldberetained.Theproce-duresuseddonotconsidermaterialvariation,purposeforobtainingthedata,specialpurposestudies,oranyconsider-ationsfortheuser’sobjective;anditiscommonpracticetoincreaseorreducethesignificantdigi...
