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C. SEPTIC SYSTEM OPERATIONAL PARAMETERS AND COMPONENTS SSS§.3.7. Efficient operation and disposal field longevity are paramount to the landowner. Environmental protection is paramount to the FED. Calculations and a description of the wastewater management system structures to be installed for the commercial coach unify these two goals. SEPTIC TANKS Septic tanks store the accumulated sludge, scum and effluent (clear zone)volumes, which in turn affect treatment of nitrogen within septic tanks. Detention Time Calculation: Detention Time =2,000 gal proposed tank capacity x 0.30 (30%volume lost to sludge/scum accumulation) 1.5 (Peaking factor) x 206 + 120 = 326 gals/day(Total ADF) Detention Time= 1.2 days. The minimum acceptable detention time is 1.0 days. Therefore, a 2,000 gallon septic tank is suitable for sufficient detention time based upon an average daily flow of 326 gaWday. Since there is concern regarding the rapid permeability of the receiving soils, a second 2,000 gallon septic tank will be installed in series behind the first 2,000 gallon tank. This will allow for greater nitrogen decomposition of the influent on the order of 3%to 15%, and possibly higher. Each tank will be a standard two-compartment tank with effluent filters installed on both outlet tees. With a 4,000 gallon total septic tank capacity,the tanks could theoretically manage 800 gallons per day with sufficient hydraulic retention time (HRT). FILTER BED REQUIREMENT CALCULATIONS BASED ON SAN JOAQUIN COUNTY SEWAGE STANDARDS: Base Tank Capacity= 1,200 gals. Leachline Equivalent Requirement= 1,200 gallons BTC + 326 ADF x 0.200 Sand Soil Factor(SF)= 305 lineal feet of leachline (LFLL). Filter bed square footage= 305 LFLL x 3 (multiplier for sandy soils) =915 sq ft. However, calculating the filter bed area using the maximum ADF of 800 gals/day that the proposed two -2,000 gallon septic tanks can manage without exceeding the maximum hydraulic residence time (HRT) of one day= 1,200 gallons BTC + 800 gals ADF x 0.200 Sand Soil Factor(SF) =400 LFLL. 400 x 3 = 1,200 sq ft of filter bed. Therefore, a maximum-sized filter bed is proposed to be installed, with a west-southwest orientation of 12 ft wide and 100 ft long= 1,200 sq ft. The filter bed will operate under gravity and have four-inch dia. laterals, each three ft apart from the sides of the filter bed and laid with a grade of 2"/100 ft. A four-hole distribution box will be required with speed-levelers®installed. The 100%reserve area can easily be accommodated to the immediate south or west of where the proposed primary filter bed is to be installed. 9