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WASTEWATER CHARACTERISTICS NLS§31 To quantify the anticipated nitrogen concentration of the septic tank effluent for use in the nitrate loading calculations, wastewater sources referenced above will be assessed. As referenced, all fecal matter will be picked up by hand and not washed into the septic system. This procedure will greatly reduce the nitrogen within the d in the subsequent effluent disposal. Using a very conservative standard concentration olCl13 m total nitrogen for influent from the employee restroom use and applying this volume as only 14%of the total ADF, brings this concentration down to 16 mg/L total N. The kennel wash-downs and dog bathing will contribute the next highest nitrogen concentration, which is indeterminable but can be considered to be a very low concentration due to the dilution effect from the addition of wash water. However mg/L total N will also be used for calculation purposes, for a total nitrogen loadi of 32 m The remaining sources (washing machine, dishwasher, dog bathing will contribute no nitrogen and account for 75%of the total wastewater volume). Table 5 below illustrates the analyses from various sources and documents using 113 mg/L as the nitrogen concentration from other commercial septic system effluent. TABLE 5 Laboratory Crites and Crites and U.S.E.P.A. ANALYTE Analysis of Tchobanoglous: Tchobanoglous: Commercial Septic With Effluent Filter Without Effluent Filter System Effluent Ammonia Nitrogen 103 mg/L 40 mg/L 40 mg/L 6-18 ing)I (NH,-N) Organic Nitrogen 10 mg/L 28 mg/L 28 mg/L 30-82 mg/L Nitrate BDL BDL BDL BDL Total Nitrogen 113 mg/L 68 mg/L 68 mg/L 35-100 mg/L Total Suspended Solids 72 mg/1, 80 mg/L 30 mg/L 200-290 mg/1. (TSS) Biochemical Oxygen 21 mg/I, 180 Ing/I. 130 mg/L 200-290 mg/L Demand(BOD:) PH 7.7 N/A N/A N/A Total Alkalinity 983 m;/I. 60-120 mg/L 60-120 mg/L N/A B. CALCULATED NITRATE-NITROGEN LOADING NLS§31 The calculated or estimated nitrate-nitrogen impact to the soil and ultimately to the groundwater is difficult to determine due to the number of variables involved. These variables include 1.)Variability in wastewater flows, nitrogen concentrations and dilution effects that may occur, 2.)Impact from previous on- site operations causing nitrate soil concentrations,3.)Upgradient nitrate sources from agricultural farmland, 4.)Changes in groundwater directional flow and elevation, 5.) Denitrification potential of the underlying soil, and 5.) Rainfall recharge. Various scientific methods are used to estimate nitrate-nitrogen loading. This study uses the Hantzsche /Finnemore Formula to predict the average concentration of nitrate-nitrogen in effluent recharge water. 8