Laserfiche WebLink
r <br /> August 15,2003 <br /> Job Number:LG03-221 <br /> Page 10 <br /> Please refer to Plate 8 for details regarding the deep percolation of rain. The nitrate <br /> concentration of rain fall was estimated to be 1 mg/L-N by Hantzshe and Finnemore(1991). <br /> 7.4 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 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. Due to the sandy soils which <br /> exist on the site, the denitrification factor is estimated to be about 15 percent. <br /> 7.5 Nitrate Loading Scenarios <br /> One nitrate loading scenario was performed to determine the impact from the winery septic <br /> — systems and deep percolation of rain water. For each scenario, the previously described <br /> assumptions were unitized in the Hantzshe and Finnemore equation. <br /> Table 6. <br /> Summary of Nitrate Mass Balance Analysis. <br /> Scenario Result Acres Average Effluent Leachfield Deep Percolation <br /> (Ne)* (A) Daily Concen- Denitrifi- of Rainfall(R) <br /> Flow(Q) tration cation(d) (Plate 8) <br /> (Table 5) (Nw) <br /> Standard Septic 1.1 mg/L-N 39.0 28 gpd 45 mg/L-N 15% 6.84 in <br /> _ <br /> System(Plate 9) <br /> * Maximum contaminate level(MCL)for Nitrate in drinking water is 10 mg/L-N. Estimate does not include the <br /> contribution from agriculture. <br /> As a result of the nitrate loading balance, it is estimated that septic wastewater generated from <br /> the proposed small winery facility will not cause a build up on nitrate above 10 mg/L-N. The Nc <br /> value was estimated to be 1.1 mg/L-N which is well below the nitrate maximum contaminate <br /> level (10 mg/L-N) for drinking water established the U.S. Environmental Protection Agency. <br /> ?pE RSO <br /> 1 <br /> ► r <br /> � Z w <br /> Q A <br /> 1 r <br /> SSOL♦ <br />