Laserfiche WebLink
Bird Road Facility Page 11 of 13 <br /> Project Number: E07183A <br /> November 30, 2007 <br /> 113.4.2 Denitrification Estimate <br /> 0 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 (NZ) to the atmosphere. <br /> Denitrification is expressed as a percentage, and the normally accepted range is 10 percent to <br /> 35 percent. Soils with higher clay content, moist soil conditions, high pH, and organic material <br /> denitrify by about 35 percent, and soils with high sand content and fast percolation rates are <br /> estimated to denitrify ata we rate, about 10 percent to 15 percent. <br /> A denitrification factor f 2S p rcent was selected for the Site because of the fine grained <br /> nature of the soils. <br /> ---_ II.3.5 Nitrate Loading Scenario <br /> A nitrate loading scenario was performed to determine the impact from the proposed project. <br /> The scenario utilizes variables discussed previously which represent the estimated <br /> conditions and uses socia d with this project. The following table presents two scenarios; <br /> the first scenario us .. 23.5 Cres in the equation ich�is the proposed roject area, and the <br /> second scenario use the t al property acreage 42.39 #res. Th owing tab presents a - <br /> summary of the nitrate ding calculation for the s' e, a resente in Plate 10. <br /> Table S. <br /> Summary of Nitrate Mass Balance Equation. <br /> F1Result 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 23.5 678 51.60 25% 2.52 <br /> I-; 1 4.0 42.39 678 51.60 25% 2.52 <br /> F1 *Maximum contamina lev (MCL)for nitrate in drinking water is 10 mg/L-N. <br /> F! II.3.6 Impact of Nitrate Loading toar ater Sources <br /> l <br /> Since the Site is relatively flat, 4e donot f esee percolating effluent affecting any surface / <br /> water resources. <br /> 11.4 Discussion of Nitrate Loading Results <br /> II.4.1 Total Nitrate Impact <br /> Based on the method and assumptions described, the result of the nitrate loading balance <br /> indicates that the proposed development on the proposed parcels should not cause a build up <br /> of nitrates in the aquifer above 10 mg/L-N. <br /> t ! <br /> fl <br /> 902 Industrial Way-Lodi,CA 95240-209.367.3701 -Fax 209.369.4228 ©2007 Neil O.Anderson&Associates,Inc <br />