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CONCLUSIONS AND RECOMMENDATIONS In summary, the soil conditions examined near the proposed septic system drain field were found to be suitable for a standard septic system utilizing leach lines or a filter bed. A satisfactory soil percolation rate of 6.41 min/in was observed in the shallow soil zone. The soil in the test location was found to sandy silt. The depth of ground water based on recent aquifer levels is approximately 27 to 33 feet below ground surface. The ground -water flow is to the south at a rate of 4 to 7 feet per mile in the vicinity of the Site. Because of the percolation rate between 5.0 and 30.0 min/in encountered in the shallow test hole, the San Joaquin County Environmental Health Department will require an eight -foot separation from the bottom of the dispersal system to ground water. Based on the anticipated depth to ground water, no modifications to standard shallow septic systems should be required to fulfill this requirement. No wells are currently located on the Site, and no water sample was collected. A new domestic well will be drilled on the Site in the future; it is assumed that the well will be tested for water quality once construction is complete. Based on the methods and assumptions described, the nitrate loading calculations indicate that the use of an on-site septic tank and drain field system on the Site has the potential to cause a buildup of nitrate in the aquifer up to 5.2 mg/L-N for a four-bedroom house or 5.9 mg/L-N for a five -bedroom house, both well below the MCL of 10 mg/L-N. As a result, no nitrate mitigation is recommended at this time. LOGE 2103 Page 13