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rTr�B7. CALCULATED NITRATE-NITROGEN LOADING The calculated nitrate-nitrogen impact to the soil and ultimately to the groundwater is difficult to determine due to the large number of variables involved, and variables unknown at this time. These variables include: 1.) Future installation methods and design of the on-site septic system for a future project, 2.)Impact from upgradient nitrate sources, 3.)Variability in wastewater flows, nitrogen concentrations and dilution effects from effluent and stormwater recharge, 4.) Changes in groundwater directional flow and elevation, 5.)Denitrification potential within the soil environment and within the confined and unconfined aquifers and 6.) Potential landscape uptake of nitrogen. Various scientific methods exist to estimate nitrate-nitrogen loading. This study uses the k Hantzsche/Finnemore Formula to predict the average resultant concentration of nitrate-nitrogen in effluent recharge water. As calculated below, the property has been assessed on a total areal loading basis correlated with the total number ofpeople on-site everyday of the year. These two factors primarily dictate the average resultant concentration of nitrate-nitrogen in the recharge water, which cannot exceed 10 ppm nitrate-nitrogen (45 ppm as nitrate). As referenced, the current water table nitrate concentration has been measured at 71 ppm N031 which should be considered the baseline. Depending upon the interpretation of the Porter-Cologne Water Act, it is assumed that the nitrate concentration of the resultant septic system effluent e cannot exceed this current water table concentration of 71 ppm NO3. The following Calc a i ns d onstrate t esul t effluent recharge water from a proposed future project will not exce d 10 ppm NO3-N, o 45 ppm 03. This is a 37% = reduction in nitrate concentration between the recti gc effl t and the a 'sting w ter table nitrate concentration. PREDICTED NITRATE- TROGEN LOADING OM A COMPLETELY BUILT- OUT PROJECT USIN AN E.H.D. APPROVED S PTIC SYSTEM. THE MAXIMUM NUMBER OF PEOPLE PN 213-270-14 1.03 Acres AN SUPPORT WITHOUT EXCEEDING THE M.C.L. OR NITRATE (10 PP NO3-N) = HA NTZS CHEIFINNEMORE EQUATION f +R Nb Nr= (I+ R) Values and Assumptions: I=7 eo Ie Maximum x 15 als/ erson/d x 365 d/ r=38 325 als=total WWI =5 124 cu ft= 1.38 in/yr 1.03 Ac x 43,560 sq ftlAc x (1 fU12 in) Nw= 103 mg NIL d = Assume 20% due to fine-grained soil R = 10 in/yr. Nb= Assumed to be 0.1 ppm NO3-N 11 Chesney Consulting