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TABLE 2 PERCOLATION TEST RESULTS WITH CORRESPONDING APPLICATION RATES IN GALLONS / FT2 / DAY 36 INCH PERC TEST 50.0 min/inch / 0.467 gallons/f 2/day 8 FT PERC TEST 17.9 min/inch / 0.729 gallons/fe/day 20 FT PERC TEST 125.0 min/inch / 0.786 gallons/f 2/day Application Rates adapted from Waste Quality Control for Siting, Design, Operation and Maintenance of On-site Wastewater Treatment Systems, based on the Pere Rate. D. GROUNDWATER INFORMATION NLS§ 2.1, SSS§ 4.1. Groundwater depths and elevations throughout San Joaquin County are illustrated on maps published by the County Flood Control and Water Conservation District. The 1999 Lines of Equal Depth Map illustrates the water table to be approximately 25 ft. 1999 is regarded as one of the highest (shallowest) depths to groundwater on record. The Spring 2018 Lines of Equal Depth Map illustrate an approximate 30 ft depth to the water table revealing a drop in water table elevation due to pumping and limited recharge during serious drought periods. Consequently, sufficient distance exists between the soil-effluent interface and the highest anticipated depth to groundwater, which must be five ft based on the perc test results. From the Spring 2018 Lines of Equal Elevation Maps, groundwater directional flow is in a north- northwesterly direction. NLS§ 2.2,3.1, SSS§ 2.1, 4.2. As referenced, properties to the north, south, east and west are currently in open land, commercial/industrial, the town of French Camp, and agricultural. Considering this area was farmed for decades, there is a potential for nitrate contamination of the underlying groundwater from nitrogen fertilizer applications and residual organic matter decomposition. NLS§ 2.3, SSS§ 4.3, 4.4, 4.5, 4.6. Since the facility is classified as a Small Public Water System, a water sample was not obtained from the onsite active domestic wells pursuant to EHD requirements. The EHD does require however, a California Drinking Water Watch document, found in Appendix D. Calculation,on the Alkalinity Requirement for Nitrification The nitrate-nitrogen loading calculations are contingent upon the environmental factors required for nitrification to occur. These conditions include soil pore-space oxygen content, soil temperature, pH, electrical conductivity, organic matter, cation exchange capacity, and alkalinity. Alkalinity in wastewater effluent is derived from the water source, in addition to the introduction of wastes. Nitrification consumes approximately 7.1 mg of alkalinity for every mg of ammonia- nitrogen (NH4-N) oxidized. Nitrification of the NH4-N concentration of 67.4 mg NIL, as determined from the septic tank analysis, would require: 67.4 mg/L x 7.1 mg CaCO3 = 479 mg/L alkalinity. The alkalinity in the effluent wastewater was tested at 472 mg/L. Page -4- Chesney Consulting