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April 25;2001 <br /> Job Number:LGOI-048 <br /> Page 9 <br /> CThe Hantzsche and Fennemore' equation takes into account development area, soil <br /> denitrification factor, rainfall volume, rainfall mtiate concentration; the waste effluent quantity, <br /> and waste'effluent nitrate concentration. 'The formula, assumptions and calculations used for the <br /> analysis are shown on Plates 4 through 8. The units of nitrate used in the mass balance equation. <br /> are nitrate-N,whose maximum drinking water contaminate level is 10 mg/l. <br /> F11 Denitrification:is an iM ortant cess ro. in septic stems that normally occurs in the leach <br /> p p p Y Y <br /> line whereby certain bacteria utilize the oxygen in the nitrate(NOA and release nitrogen.gas (Nz) <br /> F". <br /> to the atmosphere: Denitrification is expressed as a percentage, and themormally accepted range' <br /> -i's 10 perceni.to 35 percent_- Soils with higher'clay content, tnoist 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 1.0 percent to 15 percent.Diue to <br /> e coni-non occurrence of dark colored (organic layer)-clayey surface soils, the denitrificationT <br /> ,,factor is estimated to be about'25 ercent. ' <br /> An estimate of the,quantity and quality of effluent is required for the analysis therefore , <br /> the following information was used in,the calculation. The deep percolation of rain was. <br /> F: estimated to be 2.45 inches and'the calculation is shown on Plate 4. The nitrate concentration of <br /> rain fail.was-estimated to be 0.17 mg/L-N.' <br /> p <br /> Nitrates from Se tic S 's#em <br /> The.quantity of effluent waste water was estimated to be 50 gallons per person per day. A <br /> home was estimated to include as many as 5 persons so the daily total is about 250 gallons (See <br /> Table 5). The average nitrate concentration of the typical residential septic waste is normally <br /> F considered to be 45 mg/L-N.' <br /> Table 5. <br /> Total Estimated`Effluent. <br /> (see worksheets in Appendixfor calcidations) <br /> Categoity Quantity People Daily effluent quantity for each analysis i <br /> Residence 50 gallons/daylperson 5 50 gallons/day/person x 5 people=250 gallons/day <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 />