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CONCLUSIONS AND RECOMMENDATIONS • <br /> In summary, the soil conditions examined near the proposed septic system drain field <br /> appear to be suitable, though shallow ground water was encountered which may <br /> necessitate a modified septic system. <br /> A satisfactory soil percolation rate of 10.9 min/in was observed at the test location. <br /> Based on the current project, the use of on-site septic tanks and drain field systems on <br /> the Site is not expected to cause a buildup of nitrate in the aquifer above 1.13 mg/L-N <br /> with typical use, or 1.63 mg/L-N with the maximum potential occupancy. These levels <br /> fall well below the US EPA drinking water recommendation of 10 mg/L-N. <br /> A water sample was collected from the domestic well on the Site. Neither nitrate nor <br /> DBCP was detected in the sample. <br /> Live Oak encountered ground water at a depth of 3.6 feet below ground surface in the <br /> proposed septic system area. Because of recent heavy rains, it is unclear whether the <br /> water encountered was true ground water or may represent downward-percolating <br /> rainwater. <br /> We believe the Site suitable for the use of septic systems utilizing leach lines or a filter <br /> bed. The San Joaquin County On-Site Wastewater Disposal Standards (2016) • <br /> indicates that a percolation rate between 5 and 30 min/in requires eight feet minimum <br /> separation from the bottom of the dispersal system to ground water. <br /> Two options exist for the proposed septic system. The project could proceed with an <br /> engineered septic system designed for the shallow ground water encountered. It may <br /> also be possible to wait several months for excess rainwater to recede and retest the <br /> depth to groundwater prior to designing the septic system. <br /> Based on the satisfactory result of the nitrate loading calculation, no nitrate mitigation is <br /> recommended. <br /> LOGE 1708 Page 18 • <br />