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CONCLUSIONS AND RECOMMENDATIONS In summary, the soil conditions examined near the church septic system expansion area appear to be suitable. Satisfactory soil percolation rates of 14.7 min/in (at 3.30 feet deep) and less than 3.1 (at 11.50 feet deep) were observed at the test location. Ground water is anticipated to be encountered approximately 47 to 49 feet below ground surface at the Site. The ground-water flow direction is toward the southeast or east at a rate of approximately 4.5 to 10 feet per mile in the vicinity of the Site. The 1983/1999 high ground-water level for the area was approximately 35 feet below ground surface. Because of the percolation rate between 1.0 and 5.0 encountered in the deep test hole, the San Joaquin County Environmental Health Department will require a 20-foot separation from the bottom of the dispersal system to ground water. The Site is located within a "shallow only" septic zone per current San Joaquin County Environmental Health Department policy. Future construction should be restricted to shallow systems; based on the anticipated ground-water depth, no modification to standard systems should be required. The on-site domestic water well was tested for nitrate and DBCP. DBCP was not detected in the sample. Nitrate was detected in the water sample at a concentration of 9.0 mg/L-N, below the US EPA's Maximum Contaminant Level (MCL) of 10 mg/L-N. Live Oak previously sampled the domestic well on March 22, 2016, before construction of the church facility; nitrate was detected at a concentration of 11.4 mg/L-N, and DBCP was not detected. The decreased nitrate concentration between 2016 and 2019 suggests that the existing church septic system has not contributed to elevated nitrate levels in the ground water; nitrate in the area may derive from other sources. Based on the current development and proposed expansion, the use of on-site septic tanks and drain field systems on the Site is not expected to cause a buildup of nitrate in the aquifer above 3.3 mg/L-N. This level falls well below the US EPA drinking water recommendation of 10 mg/L-N. We believe the Site suitable for development with the use of standard septic systems utilizing leach lines or a filter bed. Based on the favorable result of the nitrate loading calculation, no nitrate mitigation is recommended. LOGE 1917 Page 15