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Appendix A <br />BOD and TSS are categorized into five strength classes, as shown in Table A-1. <br /> <br />Table A-I <br />Wastewater Strenoth Classes <br />Strength Class BOD SS <br /> (mg/I) (mg/I) <br /> <br />Low Strength & Residential L 150 150 <br />Medium Strength M 300 300 <br />High Strength H 500 500 <br />Very High Strength VH 700 700 <br />Super High Strength SH 900 900 <br /> <br />For each development type, the contributed pounds per unit is determined based on the dry season <br />average flow requirement and the assigned strength class, as demonstrated below for a single family <br />dwelling unit. <br /> <br />Strength Dry Season Concentration Pounds/I Pounds per Unit <br />Class Average Flow (mg/I) (lbs/unit) <br /> Requirement <br /> (mgd) <br /> <br />L 239/1,000,000 X 150 x 8.345 = .299 pounds/unit <br /> <br />The resulting 0.299 is shown in Table 1, as the BOD and TSS capacity requirements for a single family <br />dwelling unit. Appendix D in the SDC methodology provides the estimated pounds per unit for <br />various development types, based on similar calculations. The assignment of strength classification to <br />each development type is based on industry reference data. <br /> <br /> <br />