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LOGE 2211 Page 13 CONCLUSIONS AND RECOMMENDATIONS In summary, the soil conditions examined near the proposed septic system drain fields were found to be suitable for standard septic systems utilizing leach lines with seepage pits. A satisfactory soil percolation rate of 31.25 min/in was observed in the shallow soil zone at the test location. The soil in the test location was found to be clay. The depth of ground water based on recent aquifer levels is approximately 76 to 83 feet below ground surface. The ground-water flow is to the east at a rate of approximately 12 to 30 feet per mile. Because no wells are present, no water sample was collected as part of this investigation. Based on maps reviewed, nitrate does not appear to be a problem in the area; DBCP is present in some nearby wells at levels below the MCL. Based on the methods and assumptions described, the nitrate loading calculation for each parcel of the Site indicates that the use of an on-site septic tank and drain field system has the potential to cause a buildup of nitrate in the aquifer up to 10.4 mg/L, roughly equivalent to the maximum drinking water standard of 10 mg/L-N. Due to the conservative nature of the calculation, depth to water, clay soil type, and lack of known nitrate exceedances in the area, it is the opinion of Live Oak that the project is unlikely to lead to nitrate levels in excess of the MCL. Septic system construction should follow the San Joaquin County On-Site Wastewater Treatment Systems Standards (2017) where applicable.