Designation:E2717−11StandardPracticeforEstimatingtheEnvironmentalLoadofResidentialWastewater1ThisstandardisissuedunderthefixeddesignationE2717;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticeprovidesasetofinstructionsforestimat-ingtheenvironmentalloadofresidentialwater,asitisdischargedfromaresidence.Theenvironmentalloadiscalcu-latedbasedonthenumberandtypeoffixturesinthehome,thecommonhouseholdchemicalsused,andthenumberofpeopleinthehome.Whiletheformatisbroadlyappliedinternationally,theparametersstatedhereinreflectNorthAmericanaveragesandwouldneedtobemodifiedifusedelsewhere.1.1.1AveragesMethod—TheAveragesMethodprovidesanestimateoftheannualenvironmentalloadfortheaverageU.S.single-familyhomebasedon2000U.S.Censusand2007U.S.CensusDataandU.S.EPA⁄625⁄R-00⁄008characteriza-tionofresidentialwastewaterflows.1.1.2UniqueProductParametersMethod—TheUniqueProductParametersMethodprovidesanestimateoftheannualenvironmentalload,wherethehome/productparametervaluesarethesameasthoseusedfortheAveragesMethodexceptforestimatedamountsofchemicalcontaminantslistedinTable1oraveragetotalannualuseofproductsaslistedinTable1,orboth.1.1.3AdjustedAveragesMethod—TheAdjustedAveragesMethodprovidesanestimateoftheannualenvironmentalload,wherehome/productparametervaluesdifferfromthoseusedfortheAveragesMethod,exceptthatchemicalcontaminantsassociatedwithproductsdonotvary.(Table1remainsthesamefor:TypicalWaterContaminants,EstimatedAmountofContaminantinProduct(%),andthePercentWaste.)1.1.4Additional/AlternativeChemicalsMethod—TheAdditional/AlternativeChemicalsMethodprovidesanesti-mateoftheannualenvironmentalload,ofchemicalsusedthatarenotlistedinTable1.1.1.5TheUniqueProductParametersMethod,AdjustedAveragesMethod,andAdditionalChemicalsMethodmaybeusedincombinationwitheachother.1.2...
