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The following calculation illustrates that a 1,200 gallon septic tank will allow sufficient influent hydraulic residence time(HRT)within the septic tank and promote nitrogen decomposition. A Polylok TM PL-122 effluent filter must be installed on the outlet tee of the septic tank. Detention Time: Detention Time= 1.200 gal septic tank capacity x 0.80(20%volume lost to volume of sludge/scum accumulation) 2 (Daily Peaking factor)x 495 gals/day Detention Time=1.0 days. The minimum acceptable detention time is 1.0 day. Therefore,a 1,260 gallon septic tank is suitable for ample detention time given the extremely high ADF,and will all or greater nitrogen decomposition. f B. LEACBLINE AND FILTER BED REQUIREMENT CALCULATION BASED ON SAN JOAQUIN COUNTY SEWAGE STANDARDS FOR COMMERCIAL SEPTIC SYSTEMS: Base Tank Capacity(BTC)= 1,200 gal. Leachline Equivalent Requirement= 1,200 gallons BTC +495 ADF x 0.200 sand Soil Factor(SF)=339 lineal feet of leachline(LFLL) required. Filter Bed Requirement: 339 LFLL x 3 (sandy soils)= 1,017 sq ft. Primary disposal area designated on the Site Plans: 20 ft N-S x 50 ft E-W = 1,000 sq ft calculated filter bed disposal area. The secondary disposal area(100% Replacement Area)is also designated to be the same area at 1,000 sq ft and is proposed to be directly south of the primary area. When failure occurs, approximately ten parking stalls must be removed and the replacement disposal area installed. These 10 removed parking stalls will then be relocated to south of the entrance driveway where there are 14 proposed spaces and area for 15 additional parking stalls. Consequently, ample area exists for the 100% replacement area and for the relocation of parking stalls. The filter bed should be installed as high in elevation as possible to take advantage of evapotranspiration, consequently,the septic tank must be installed as high in elevation as possible. Therefore, influent lines from the break room sink and restrooms must come through the tops of the building footings and not under the footings. The project plumber and septic system contractor must coordinate to ensure this occurs. The Plan Dimensional View of the filter bed, as proposed, is found in Appendix A. The proposed operation of the wastewater management system is as follows: Graywater from sinks and blackwater from toilets will flow into a 1,200 gallon,two compartment septic tank. As referenced, a PolylokTM PL-122 effluent filter must be installed on the outlet tee of the septic tank. Effluent will gravity flow west to a distribution box (D-box) at the east-center of the primary filter bed. The D-box must be level and be installed with Tuff Tite® Speed LevelersTM to achieve optimum and equal effluent distribution. Equalized effluent volumes will gravity flow west into three separate perforated leachlines,which should be installed as level as possible. 10