Laserfiche WebLink
September 20,2002 <br /> Job Number: LG02-261 <br /> Page 9 <br /> Table 5. <br /> Total Estimated Daily Usage of Septic System. <br /> Category Effluent usage People Effluent quantity per category <br /> for each per day <br /> category <br /> New 3-bedroom home 75 gals 4 4 people* 75 gal/person-day=300 gal/day <br /> 2-bedroom,second dwelling unit 75 gals 3 3 people* 75 gaUperson-day=225 gal/day <br /> Average Daily Flow: 525 !1! /da <br /> Denitrification is an important process in septic systems that normally occurs in the leach <br /> line whereby certain bacteria utilize the oxygen in the nitrate (NO3) and release nitrogen gas (N2) <br /> to the atmosphere. Denitrification is expressed as a percentage, and the normally accepted range <br /> is 10 percent to 35 percent. Soils with higher clay content, moist soil conditions, high pH, and <br /> organic material denitrify about 35 percent and soils with very high sand content and fast <br /> percolation rates are estimated to denitrify at a lower rate, about 10 percent to 15 percent. Due to <br /> the sandy soils, the denitrification factor is estimated to be about- 0 er=t. <br /> An estimate of the quantity and quality of rainfall was required for the analysis. The deep <br /> percolation of rain was estimated to be 6.84 inches and the calculation is shown on Plate 8. The <br /> nitrate concentration of rain fall was estimated to be 0.17 mg/L-N.' <br /> Nitrates from Agriculture <br /> Leaching losses of nitrate fertilizer occur when soils have more incoming water(rain or <br /> irrigation)than the soil can hold. As water moves through the soil, the nitrate (NO3")that is in <br /> soil solution moves along with the water. Ammonium (NH4`) forms of N have a positive charge <br /> and are held by the negative sites on the clay in the soil; therefore,NH4' forms of N leach very <br /> little. In sands where there is very little clay, ammonium forms of N can leach. Coarse-textured <br /> sands and some muck soils are the only soils where ammonium leaching may be significant. <br /> One way to minimize N leaching and denitrification is to minimize the time the N is in the soil <br /> before plant uptake. This cuts down on the time when conditions are favorable for losses.' <br /> .- Proper management of agricultural property significantly reduces the potential nitrate impact to <br /> ground water. <br /> ' Vitosh,M. L.,J. W.Johnson and D. B.Mengel,July 1995.Tri-state Fertilizer Recommendations for <br /> Corn, Soybeans,Wheat and Alfalfa,Extension Bulletin E-2567. <br /> ?OE ASO <br /> Z <br /> O � <br /> SSS O G♦ <br />