Laserfiche WebLink
F1April 29,2005 <br /> NOA Project Number: E05040A <br /> the long-term average concentration for total nitrogen in waste water is estimated to be 45 mg/.L-N. <br /> ri <br /> 4.4.2 Denitrification Estimate <br /> FJq <br /> Denitrification is an important process which occurs within the leach field whereby certain bacteria <br /> utilize the oxygen in the nitrate (NO3) and release nitrogen gas (N� to the atmosphere. <br /> Denitrification is expressed as a percentage, and the normally accepted range is 10 percent to 35 <br /> 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 at a lower rate, about 10 percent to 15 percent. <br /> ii <br /> A denitrification factor of 15 percent was selected for the Site. <br /> 4.5 Nitrate Loading Scenario <br /> A nitrate loading scenario was performed to determine the impact from the'proposed project. The <br /> ri scenario utilizes the variables discussed previously which represent the estimated conditions and <br /> uses associated with this project. The following table presents a summary of the nitrate loading <br /> calculation for each parcel. <br /> Table 2. <br /> Summag of Nitrate Mass Balance Analysis. <br /> Result <br /> Average Daily Effluent Leachfield Deep <br /> Acres Flow(Q) Concen- Percolation of <br /> I { Plate {Nc)'� (A) (Table 3) tration(Nw) Denitrifi- Rainfall(R) <br /> I E (mg/L-N) cation(d) <br /> + (gpd) (mg/L-N) (Plate 9) (in.) <br /> 10 8.3 9.81 630 45 15% 3.54 <br /> (Parcel 8) <br /> 11 8 3 9.81 630 45 15% 3.54 <br /> t (Parcel 9) <br /> 12 8.3 9.81 630 45 15% 3.54 <br /> (Parcel 10) <br /> 13 8.3 9.81 630 45 15% 3.54 <br /> (Parcel 11) <br /> 14 T6 9.81 560 45 15% 3.54 <br /> (Parcel 12) <br /> (17ar1113) 8.3 9.81 630 45 15% 3.54 <br />` <br /> Fill <br /> 16 <br /> (Parcel 14) 8.3 9.81 630 45 15% 3.54 <br /> 5 <br /> F <br />