Laserfiche WebLink
New Moose Lodge Nitrate Loading Study Page 5 of 7 <br /> Our Project Number: E07175A <br /> November 5, 2007 <br /> Wei ted Average Calculation <br /> X468 gpd 5mg�L-N 39,780 gpd-mg/L-N <br /> ✓50 gpdm /L-N :;-- 250 gpd-mg/L-N <br /> 468 gpd + 50 gpd = 518 gpd <br /> X39,780 gpd-mg/L-N + 250 gpd-mg/L- —_4&,030-gpd-mg/L-N <br /> 40,030 gpd-mg/L-N / 518 gp77.3 mg/L-N ' <br /> i <br /> It is estimated that the average concentration for total nitrogen in waste water for the project is <br /> approximately 77.3 m L-N over the long term. <br /> 3.4.2 Denitrification Estimate <br /> Denitrification is an important process which occurs within the leach field whereby certain <br /> bacteria utilize the oxygen in the nitrate (NO3) and release nitrogen gas (N2) to the <br /> atmosphere. Denitrification is expressed as a percentage, and the normally accepted range is <br /> 10 percent to 35 percent. Soils with higher clay content, moist soil conditions, high pH, and <br /> organic material denitrify by about 35 percent, and soils with high sand content and fast <br /> percolation rates are estimated to denitrify at a lower rate, about 10 percent to 15 percent. <br /> A denitrification factor f 20 percent Was selected for the Site because of the fine grained <br /> nature of the soils. <br /> 1"3.5 Nitrate Loading Scenario <br /> A nitrate loading scenario was performed to determine the impact from the proposed project. <br /> The scenario utilizes the variables discussed previously which represent the estimated <br /> conditions and uses associated with this project. The following table presents a summary of the <br /> nitrate loading calculation for the site. <br /> Table 2. <br /> S mmary of Nitrate Mass Balance E uation. <br /> Result Average Effluent Leachfield Deep <br /> Parcel (Nc)* Acres(A) Daily Flow Concentration Denitrification Percolation <br /> (mg/L-N) (Q) (gpd) (Nw) (d) of Rainfall <br /> (mg/L-N) (R) (in) <br /> 1 4.2 22.02 518 77.3 20%.1-1 5.76 <br /> * Maximum contaminant level(MCL)for nitrate in drinking water is 10 mg/L-N. <br /> 3.6 Impact of Nitrate Loading to Nearby Water Sources <br /> Since the Site is relatively flat, we do not foresee percolating effluent affecting any surface <br /> water resources. <br /> '-'44 <br /> 902 Industrial Way-Lodi,CA 95240-209.367.3701 -Fax 209.369.4228 02007 Neil O.Anderson&Associates,Inc <br />