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FHantzschelf <br /> innemore Equation <br /> W ,(1 - d) +RNh <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 loss due to denitrification in the soil <br /> R = Average recharge rate of rainfall- inches per yr NLS§3.2 <br /> Nb= Background NO3 N concentration of rainfall recharge, exclusive of wastewater influences(ppm NO,-N) <br /> Values and Assumptions <br /> I= 2,360 gpd x 365 d/yr = 861,400 gals=total WW/yr= 11,516 cu ft = 11.3 in. <br /> 2.81 Ac x 43,560 sq ft/Ac x(1 ft/12 in.) <br /> Nw = mg N/L=25.3 TKN. <br /> d = Assume 25%as explained on Page 3 of the Phase I Report. <br /> R = 14 in/yr. <br /> Nb= Assumed to be 0.1 ppm NO3-N. <br /> 11.3 in6j(25.3 mg N/L) (1 - .25)+(14 in/yr x 0.1 mg/L) <br /> Nr = (11.3 in/yr+ 14 in/yr) <br /> Nr = 8.5 ppm as nitrate-nitrogen(NO3-N)or 38 ppm as nitrate(NO3) <br /> The estimated nitrate loading concentration in the recharge effluent is calculated to be under the <br /> Maximum Contaminant Level (MCL) limit for nitrate in drinking water. <br /> Crites/Tchobano-lour Formula <br /> LN = LW CNF <br /> where: <br /> LN = nitrate-nitrogen loading in lbs/ac-day <br /> LW = wastewater loading in gals/ac-day=2,360 gals/day 2.81 ac = 839.9 gals/ac-day <br /> CN = TKN nitrogen concentration determined to be 25.3 mg/L <br /> F= Conversion factor: 8.34 lbs/[106 gal-(mg/L)] <br /> LN= 839.9 gals/ac•day x 25.3 mg/L x (8.34)(106)= 0.181bs N/ac•day x 365 days/yr= <br /> 64.7 lbs N/ac/yr. <br /> Page 6 of 11 <br /> Chesney Consulting <br />