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too long. Consequently, only effluent will flow to the new 2,000 gal tank from this unit. The second residential unit near the intersection of Durham Ferry and Hwy 33 will connect to a new 2,000 gal tank, as will the residential unit directly to the north. Influent from the northernmost two- story garage will also flow to the new 2,000 gal tank. This 2,000 gal tank will be directly in- between and to the east of the two main residential units. Effluent discharging from the 2,000 gal tank(with a Polylok® filter on the outlet),will travel north and connect to a new 1,200 gallon tank that will also serve the restrooms of the Prayer and Mediation Center. The second chamber of this tank will be the pump chamber with a BioTube® filter vault with an alternating duplex pump system to pressurize effluent to the new filter bed. The filter bed will be constructed directly to the west of the 1,200 gal tank as a double-depth filter bed disposal field of 800 sq ft. The 100%reserve replacement area is denoted on the Site Plans as directly west of the primary filter bed. B. SEPTIC TANKS Septic tanks store the accumulated sludge, scum and effluent(clear zone)volumes, which in turn affect treatment of nitrogen within the tanks. Detention time will be individually calculated for each of the three new tanks to be installed, and demonstrates that when the Max ADF is applied to each tank, there is still sufficient detention time: Detention Time Calculation for each of the three new septic tanks: Detention Time=2 00 gal tank capacity x 0.70(30%volume lost to sludge/scum accumulation) \_ 2,5.{Peaking factor)x 300 MAX gals/day(ADF) Detention Timq= 1,200 gal (2) tank capacity x 0.90(10%volume lost to sludge/scum accumulation 2.5 (Peaking factor)x 300 MAX gals/day(ADF) Detention Time= 1.9 days for the 2,000 gal tank and 1.4 days for the two 1,200 gal tanks to be installed. The minimum acceptable detention time is 1.0 day. r—C. PRESSURIZED FILTER BED SIZING CALCULATIONS Base Tank Capacity(BTC)= 1,200 gal. The anticipated maximum daily flow of 300 gallons may occur on any given day of the week, 365 days per year. There will be days where no wastewater flow occurs. This ADF parameter is unknown. However, the calculations are based upon the 300 gals ADF occurring seven days per week, 365 days per year. Leachline Equivalent Requirement= 1,200 gallons BTC +300 MAX ADF x 0.250 clay Soil Factor (SF) =375 lineal feet of leachline,,(LFLL) required. 375 x 4 (Clay Soil -Filter Bed Soil Factor)_ -1,500 sq. ft. filter bed area required., Due to area constraints, a double depth filter bed will be constructed and increased in area to 14 ft wide by 57 ft long= 798 sq ft(1,600 sq ft). The total depth of the filter bed will be 39 inches as illustrated on the Project Plans. Page -9-