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r�� V. CONCLUSIONS AND RECOMMENDATIONS NLS§4.1. The nitrate loading calculations show the resultant effluent from the proposed project will theoretically possess a nitrate-nitrogen concentration at 63% of the Federal nitrate Maximum Contaminant Level (MCL) of 45 ppm as nitrate or 10 ppm nitrate as nitrogen. A total nitrogen concentration that was used in the calculations was derived from the actual sampling of effluent from a septic tank installed for the Holly Commerce Center in 2017. This total nitrogen concentration provides a very accurate representation of future nitrogen loading from the project since it is assumed that the proposed A&B Warehouse Buildings will operate under similar conditions as the existing Holly Commerce Center. With regard to the Hantzsche/Finnemore Equation which was used to calculate the nitrate loading for this study, and focusing on the volume rate of wastewater entering the soil ayeraged over the gross developed area in inches per yr,the area typically used is the APN. The APN is the legally defined area for any referenced property. Although the APN area may be very small or very large, to 'rom a"unit of land,"use of the APN is the most applicable loading sources from any specific APN should be analyzed and A APN is 110.35 acres. It has been subsequently decided to only itprint of the buildings into account for the nitrate loading 10 acres. As noted in the loading calculations, by lowering the ) ac), the results reveal an average concentration of nitrate-nitrogen ;%of the MCL. sere determined to be very high in nitrogen concentration at 146 ncentration may be attributable to a lack of a dilution effect caused . By conserving water with these fixtures, an apparent increase in 1. However,the total nitrogen contribution from the proposed property remains under the nitrate MCL. A. SSS§ 5.4, 6.8. The shallow soils underlying the four proposed effluent disposal areas show a mediocre permeability at an average of 38 min/in, translating to an acceptance rate of approximately 0.43 gallons/ftZ/day. Perc testing in the proposed effluent disposal location for Building A- South showed a very slow percolation of 125 min/in, which is deemed an anomaly. Uniformly applying the effluent through equal distribution by laying the perforated drain pipe level over the entire filter bed area will allow optimum effluent management by the receiving soils and prevent soil saturation throughout the vadose zone. Taking only nitrate-nitrogen into account(not TN, TKN or NH4), we find the following: The soil nitrate-nitrogen concentration was determined to be approximately 10 ppm at the 36" depth. The water table concentration of nitrate was measured at 109 ppm. This nitrate concentration must be converted to nitrate-nitrogen for comparison purposes with the soil concentration: Page -9- Chesney Consulting