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F erage Daily Flow(ADF) in gpd is based on numbers specified on Page 2 of the Administrative e Permit, as noted in Appendix B: erage Number of Employees Per Shift= 13 erage Number of Customers Per Shift= 1 Average Deliveries Per Shift= 1 Employees/Customer/Deliveries per Work Shift= 15 Industrial buildings with no food cafeteria are set at 15 gals/person/day: 15 x 15 =225 gpd ADF. The ADF is added to the Base Tank Capacity (BTC) of 1,200 gals. This number is multiplied by the Leach Line Soil Factor(LLSF) for a loam soil structure of 0.250, based on the soil test results discussed on Page 3, to calculate the Lineal Feet of Leachline (LFLL). This number is multiplied by the Filter Bed Soil Factor (SF) of 3.5 (loam soil in-between sand and clay)to arrive at the filter bed area required: 1,200+ 225 = 1,425 x 0.225 (LLSF) = 321 LFLL x 3.5 (SF)= 1,122 ftz filter bed area. The filter bed area is proposed to be 16' x 37' with double depth drain rock(24" depth) = 592 ft'. (16+16+37+37 = 106' x 2' =212 ftz). 592 ft' +212 ftz = 804 ft2 = floor+ sidewall application area. In addition, 2 - 36" dia. seepage pits are to be installed at the north end of the filter bed. The application area of each seepage pit= 195 ftz. 804 ftz+ 195 ftz+ 195 ftz = 1,194 ftz z 1,122 ftz. Alternatively, under Section 9.7.3 of the EHD OWTS Standards, "Dispersal field application rates for engineer designated systems may also be determined using Table 3: Application Rates as Determined from Stabilized Percolation Rates as published in the Water Quality Control Policy..." The following are the disposal area calculations based on the obtained application rate as determined by the perc rate: The average acceptance rate for the three perc tests = 0.330 gallons/ftz/day. 225 gpd ADF- 0.330 gallons/ftz/day= 682 ftz required acceptance area. Therefore, double depth drain rock in the filter bed will provide sufficient acceptance area. The 100%reserve/replacement area is identical to the primary disposal area and is directly north of it, with a 10 ft separation distance between the two disposal areas. D. OPERATIONS AND MAINTENANCE PLAN Under Section 1.12.1 of the SJC OWTS Standards, an engineered OWTS "shall be operated and maintained pursuant to an Operations and Maintenance Plan (OMP) compiled by the OWTS engineer." The septic tanks and pump system, including the audio/visual alarm, should be inspected and tested yearly by a qualified professional. The tanks must be pumped, also if determined by a qualified professional. Showers should be limited to 10 minutes during each use. A timer should be made available in each shower stall to ensure this time limit is adhered to. The filter bed area must be barricaded so this area cannot be driven over or parked upon. Railroad ties, or other types of barriers such as parking blocks or a fence can be used to prevent vehicular traffic over the filter bed. Page -7- Chesney Engineering, Inc.