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B. CALCULATED NITRATE-NITROGEN LOADING NLS§ 3.3,3.4,3.5,3.6. 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 unknown at this time. These include: 1.) Variability in wastewater flows,nitrogen concentrations and dilution effects that may occur, 2.) Impact from upgradient nitrate sources, 3.) Changes in groundwater directional flow and elevation, 4.) Denitrification potential within the soil environment and within the confined and/or unconfined aquifers, and 5.) Potential landscape uptake of nitrogen. Various scientific methods exist to estimate nitrate-nitrogen loading. This Study uses the Hantzsche/Finnemore Formula to predict the average resultant concentration of nitrate-nitrogen in effluent recharge water from a conventional septic system. As calculated below, the property has been assessed on a total areal loading basis correlated with the total number ofpeople on-site every week of the year. These two factors primarily estimate the average resultant concentration of nitrate-nitrogen in the effluent, along with an est of ogen concentr he recharge water. The effluent concentration of exceed 10 ppm 'trate-ni gen(45 ppm as; nitrate). Wastewater researchers place the nitrogen reduction occurring in septic tanks at 10%to 20%. From the May 8, 2003 Symposium "Onsite Wastewater Treatment-Nitrogen Removal,"Dr. Stuart Oakley of California State University Chico states that "approximately 20% of the total nitrogen generated is removed in the septic tank" (Ref. 11). As noted below, this estimate of 20% is used for nitrogen reduction occurring in the septic tank. PREDICTED NITRATE-NITROGEN LOADING FROM A COMPLETELY BUILT-OUT PROJECT USING AN E.H.D.APPROVED SEPTIC SYSTEM: HANTZSCHEIFINNEMORE EQUATION INw(1 - dl + RNb Nr= (I +R) Where: Nr = Resultant average concentration of nitrate-nitrogen in recharge water-(ppm NO;N) I = Volume rate of wastewater entering the soil averaged over the gross developed area in inches per yr Nw = Total nitrogen concentration of wastewater in mg N/L d = Fraction (%)of nitrate-nitrogen loss first in the septic tank and then due to denitrification in the soil environment. R = Average recharge rate of rainfall - inches per yr NLS§3.2 l/ Nb = Background nitrate-nitrogen concentration of rainfall recharge, exclusive of wastewater influences (ppm NO3-N)- Values O3 N).Values and Assumptions: I= 810 gals ver meeting d x 52 meetings/yr(every Saturday)=42,120 pals=total W W/vr=5.631 cuff =0.78 in. 2.0 Ac x 43,560 sq ft/Ac x(111/12 in.) .0$3➢333 9