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IV. SE:Tthe�opnerational <br /> ITEM OPERATIONAL PARAMETERS AND COMPONENTS <br /> The plan parameters and the operational components of the wastewater treatment <br /> and disposal system for this project will be provided by the engineer-of-record,Mr. Paul Schneider,PE, <br /> V.P. of Siegfried Engineering, Inc. <br /> V. CONCLUSIONS AND RECOMMENDATIONS <br /> NLS§4.1. The nitrate loading calculations show the resultant effluent from the proposed project <br /> will theoretically possess a nitrate-nitrogen concentration well below the Federal nitrate Maximum <br /> Contaminant Level (MCL) of 45 ppm'as nitrate or 10 ppm nitrate as nitrogen. A total nitrogen <br /> concentration that was used in the calculations was derived from the actual sampling of effluent <br /> from a septic tank installed for the Holly Commerce Center in 2017. This total nitrogen <br /> concentration provides a very accurate representation of future nitrogen loading from the project <br /> since it is assumed that the E&E Building will operate under similar conditions as the existing <br /> Holly Commerce Center. <br /> The septic tank effluent analyses were determined to be very high in nitrogen concentration at <br /> 146 mg/L TKN. This high nitrogen concentration may be attributable by a lack of a dilution effect <br /> caused by waterless and low flow fixtures. By conserving water with these fixtures, an apparent <br /> increase in nitrogen concentration has resulted. However,the total nitrogen contribution from the <br /> proposed sanitary sewer septic system to serve the subject property remains under the nitrate MCL. <br /> And of significance is that by developing this Parcel, thus creating impermeable surfaces of <br /> buildings, dock areas, parking lots, etc.,this will"cap"the soil surface and prevent further <br /> migration of nitrate within the high nitrate laden soil from entering the groundwater due to rainfall. <br /> SSS§ 5.4, 6.8. The shallow soils underlying the proposed effluent disposal area show a slow but <br /> acceptable permeability at 50 min/in, translating to an acceptance rate of 0.311 gallons/W/day. <br /> Uniformly applying the effluent through equal distribution by laying the perforated drain pipe level <br /> over the entire filter bed area will allow optimum effluent management by the receiving soils and <br /> prevent soil saturation throughout the vadose zone. <br /> Taking only nitrate-nitrogen into account(not TN, TKN or NH4),.we find the following: The soil <br /> nitrate-nitrogen concentration was determined to be 189 ppm at the 24" depth, approximately 0.8 ft <br /> above the water table. The water table concentration of nitrate was measured at 85 ppm. This <br /> nitrate concentration must be converted to nitrate-nitrogen for comparison purposes with the soil <br /> concentration: 85 ppm nitrate= 19 ppm nitrate-nitrogen. Therefore, a decrease in nitrate-nitrogen <br /> concentration from 189 ppm in the soil to 19 ppm in the top water table occurs in a distance of <br /> approximately 1.5 ft; a 90% decrease. This decrease can be attributable primarily to denitrification <br /> because of anaerobic conditions within the phreatic zone along with a carbon substrate, and the <br /> lack of sufficient alkalinity. <br /> LPage-9- <br /> Chesney Consulting <br />