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r�� <br /> B. CALCULATED NITRATE-NITROGEN LOADING <br /> NLS§3.4,3.5,3.6. The calculated nitrate-nitrogen impact to the soil and potentially to the <br /> groundwater is difficult to determine due to the large number of variables involved and variables <br /> unknown at this time. These include: 1.) Impact from agricultural upgradient nitrate sources, 2.) <br /> Variability in wastewater flows, effluent nitrogen concentrations and dilution effects, 3.) Changes in <br /> groundwater directional flow and elevation, 4.) And of significant importance is not only the <br /> denitrification potential of the indigenous clay loam soils,but equally important is the diminished <br /> nitrification potential within this soil environment at the soil effluent interface. The small pore <br /> space within this soil significantly reduces oxygen content, thus impeding nitrification. <br /> The Hantzsche/Finnemore Formula is used below to predict the average concentration of nitrate- <br /> nitrogen in effluent recharge water from the proposed wastewater management system. The <br /> calculations are based on a total areal loading basis of 36 acres, correlated with the annually projected <br /> wastewater flows of 17,555 gpy. <br /> HANTZSCHEIFINNEMORE EQUATION <br /> INN,(1 - d) +R Nb <br /> Nr= (I+R) <br /> Where: <br /> Nr = Resultant average concentration of nitrate-nitrogen in recharge water-(ppm NO3-N) <br /> I = Volume rate of wastewater entering the soil averaged over the gross developed area in inches per yr <br /> Nw = Total nitrogen concentration of wastewater in mg N/L <br /> d = Fraction(%)of nitrate-nitrogen combined loss in the high clay content soil due to: <br /> 1.) Prevention of nitrification and 2.)The denitrification of nitrate molecules that may form. <br /> R = Average recharge rate of rainfall-inches per yr NLS§3.2 <br /> Nb = Background nitrate-nitrogen concentration of rainfall recharge,exclusive of wastewater influences <br /> (ppm NO3-N)- <br /> Values and Assumptions: <br /> I= 17,555 gals=total WW/X=2,347 cu ft =0.0177 in/yr <br /> 36.46 Ac x 43,560 sq ft/Ac x(1 ft/12 in) <br /> Nw= 62 mg N/L <br /> d = Assume 25%due to the high percentage of clay loam soil at the soil-effluent interface. <br /> R = 10 in/yr. <br /> Nb= Assumed to be 0.1 ppm NO3-N <br /> 0.0177 in/W(62 mg N/Q (1 -0.25)+(10 in/yr x 0.1 mg/L) <br /> Nr = (0.0177 in/yr+ 10 in/yr) <br /> Nr = 0.182 ppm as nitrate-nitrogen(NO3-N), 0.82 as nitrate(NO3) <br /> Pa e-6- <br /> Chesney Consulting <br />