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r reduction of nitrate to volatile gases, such as nitrous oxide and nitrogen gas. Favorable soil conditions for denitrification are: 1.)High organic matter content of the underlying soils, 2.)High soil moisture content(anaerobic conditions) and 3.)Alkaline soil pH. As noted on the Soil Analysis ~' Re o the surface and subsurface soils suggest a low concentration of organic matter and a slightly p � alkaline pH. The per capita ingestion and excretion of nitrogen can be considered reasonably constant with minor variations. Although there are several estimates of nitrogen inflows based upon per capita intake LI of total nitrogen per day, a conservative estimate is 17 grams N/capitalday. Concerning effluent outflows, most literature evaluates nitrogen discharged from septic systems in concentration units of mg NIL (milligrams of nitrogen per liter of effluent). There are several estimates of nitrogen effluent concentrations, however, the conservative average is generally regarded as 62 mg NIL. If a projected maximum wastewater flow of 1,400 gallons is used, the following calculations illustrate the potential nitrate loading per year: 1,400 gallons/day = 5,300 L/day X 62 mg NIL= 0.329 kg N/day X 365 days/year= 120 kg N/yr or 263.9 lbs. N/yr. The data obtained from the Soil Analysis Report suggests there are only slightly favorable �- conditions for the denitrification process, a conservative estimate being a 20% reduction in NO3-N i formation. The clogging mat which will form under the Ieachlines and at the bottoms and sides o _ the seepage pits should theoretically remove another 20% of NO3-N. Although it is impossible to predict an exact concentration of NO3-N loading, a safe assumption is 40% reduction of the total N loading ill be as nitrto-nitro en. Therefore,total NO3-N loading from the proposed project is calculated to be 263.9 lbs. - 40% reduction = 158.3 lbs. of NO3-N/yr. The project acreage consists of approximately 3.9 acres. This calculates to a yearly "per acre" M contribution of nitrate-nitrogen from the Kingdom Hall of approximately 40.6 lbs. of NO3-Nlac/yr. The existing nitrogen content of the soil environment should not be considered since the organic matter(ENR-estimated nitrogen release) and soil nitrogen is low and will not be a significant factor when the project is developed. This low impact also applies to fertilization programs of on-site �- landscaping. �.. The projected nitrate-nitrogen contribution of 40.6 lbs. NO3-N/ac/yr can be considered significant Lpotential impact. The following calculation quantifies the anticipated impact from nitrogen reported as nitrate exclusively: 40.6 lbs, x 4.4 (conversion factor) = 178.6 lbs. NO3/ac/yr. 7 Na(&y Ag Pgsearck i ,