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The details of the nitrate loading calculations are included in Plates 15 through 18. The <br />results of the calculations are presented in the following table. <br />Table 6. Result of Nitrate Loading Calculations <br />Variable Value Units Description <br />Nc <br />(Parcel A — <br />no new development) <br />4.5 mg/L-N Long-term average concentration of <br />percolating effluent, Parcel A <br />Nc <br />(Parcel A — <br />two homes) <br />8.6 mg/L-N Long-term average concentration of <br />percolating effluent, Parcel A (two homes) <br />Nc Long-term average concentration of <br />(Parcel B — 0.2 mg/L-N percolating effluent, Parcel B <br />no development) (no development) <br />Nc <br />(Parcel B — <br />two homes) <br />1.7 mg/L-N Long-term average concentration of <br />percolating effluent, Parcel B (two homes) <br />The US EPA recommended MCL for nitrate in drinking water is 10 mg/L-N. In a worst- <br />case situation, the maximum buildup of nitrates in the aquifer from the use of septic <br />systems on the Site is predicted to be 4.5 mg/L-N for the existing home on Parcel A, 8.6 <br />mg/L-N for two homes on Parcel A, 0.2 mg/L-N for no development on Parcel B, and 1.7 <br />mg/L-N for two homes on Parcel B. The results of the nitrate loading estimates for each <br />parcel are well below than the maximum drinking water standard. <br />Discussion of Nitrate Loading Results <br />Total Nitrate Impact <br />Based on the method and assumptions described, the results of the nitrate loading <br />estimates indicate that the proposed parcel split on the Site should not cause a buildup <br />of nitrates in the aquifer over 10 mg/L-N. Because of the favorable result of the nitrate <br />loading calculations, no nitrate mitigation is recommended at this time. <br />LOGE 2121 Page 14