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Denitrification is the only mechanism in the soil which can significantly reduce nitrate concentrations in percolating effluent. It is the biological and chemical 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 Report, the surface and subsurface soils suggest a low concentration of organic matter. However, since the soil moisture content becomes saturated at 7.5 feet below grade, anaerobic conditions are most likely prevalent. Additionally, the soil pH is alkaline at 7.8 which promotes a favorable environment for denitrification. As referenced earlier, soil samples retrieved from the surface to four feet were analyzed for clay content, measured by the hydrometer method(ASTM D-422). These samples were found to possess a clay content average of 41%. High clay content soil can translate to lower oxygen content (anaerobic conditions) of the subsurface soils. The cation exchange capacity (CEC) measures the potential for clay particles to adsorb NH4 ions, thus preventing nitrification. However, not all types of clays have this capability. The analyzed CEC can be considered moderately high which is representative of the indigenous clay fraction. The data obtained from the Soil Analysis Report indicates there are relatively favorable conditions for the denitrification process, a conservative estimate being a 20% reduction in NO3-N formation. The clogging mat which may form under the leachlines 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 will be as nitrate-nitrogen. Therefore, total NO3-N loading from the proposed project is calculated to be 28.3 lbs. x 40% reduction = 17 lbs. of NO3-N/yr. VII. CONCLUSIONS The project acreage consists of approximately 2.7 acres. This calculates to a yearly "per acre" contribution of nitrate-nitrogen from the Church of approximately 6.3 lbs. of NO3-N/ac/yr. It is our opinion the existing nitrogen content of the soil environment should not be considered since the organic matter(ENR-estimated nitrogen release) and soil nitrogen is currently low and will not be a significant factor if the project is developed. 7 Vaffey Ag?osearck