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CONCLUSIONS AND RECOMMENDATIONS <br />In summary, the soil conditions examined on each parcel of the Site were found to be <br />suitable for septic systems utilizing leach lines and seepage pits. Satisfactory soil <br />percolation rates of 2.45 min/in (Parcel 1) and 4.0 min/in (Parcel 2) were observed in <br />the deep soil zone at the test locations. The soils in the test locations were found to be <br />sands, silts, and clays. <br />Based on maps reviewed, the depth of ground water based on recent aquifer levels is <br />approximately 75 to 85 feet below ground surface. The ground -water flow is to the <br />northeast at a rate of approximately three feet per mile in the vicinity of the Site. <br />A water sample was collected from the domestic well on the Site as part of this <br />investigation. Nitrate was detected in the sample at a concentration of 9.7 mg/L-N, <br />below the MCL of 10 mg/L-N. DBCP was not detected in the sample. <br />Based on the methods and assumptions described, the nitrate loading calculation <br />indicates that the use of on-site septic tanks and drain field systems on the Site has the <br />potential to cause a buildup of nitrate in the aquifer up to 2.3 mg/L-N (existing <br />development on Parcel 1), 0.15 mg/L-N (no development Parcel 2), or 5.6 mg/L-N (two <br />houses, Parcel 2), well below the maximum drinking water standard of 10 mg/L-N. <br />Based on the result of the nitrate loading calculation, no nitrate mitigation is <br />recommended at this time. <br />LOGE 2150 Page 17 <br />