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Various scientific methods exist to estimate nitrate-nitrogen loading. This study will use the Hantzsche/Finnemore Formula to predict the average resultant concentration of nitrate-nitrogen in effluent recharge water. As referenced above and calculated below, the subject parcel has been assessed from the nitrate loading standpoint on an areal loading basis correlated with the total number of anticipated people (employees and customers)per workday. These two factors primarily dictate the average resultant concentration of nitrate-nitrogen in the recharge water, which should not exceed 10 ppm nitrate-nitrogen(45 ppm as nitrate). The following calculations demonstrate that the resultant effluent recharge water from the subject parcel will not exceed 10 ppm NO3-N. CALCULATED NITRATE LOADING FROM THE ANTICIPATED NUMBER OF PEOPLE THAT WILL BE ON THE SUBJECT PROPERTY DAILY = HANTZSCHEIFINNEMORE EQUATION INAI - dib Nr= (I +R) Where: Nr= Resultant average concentration of nitrate-nitrogen in recharge water- (ppm NO3-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 due to denitrification in the soil R = Average recharge rate of rainfall - inches per yr Nb= Background nitrate-nitrogen concentration of rainfall recharge, exclusive of wastewater influences (ppm NO3-N) Values and Assumptions I =47 people x 15 gals/person/d x 260 work d/yr= 183,300 gals=total WW/yr=24,505 cu ft= 0.89 in/yr 7.55 Ac x 43,560 sq ft/Ac x (I ft/12 in) Nw= 103 mg N/L d = Assume 20% due to a fine-grained soil R = 13 in/yr. Nb= Assumed to be 0.1 ppm NO3-N 0.89 in/yr(103 mg N/L) (1 - 0.20) + (13 in/yr x 0.1 mg/L) Nr = (0.89 in/yr+ 13 in/yr) Nr = 5.4 ppm as nitrate-nitrogen(NO3-N) or 23.9 ppm as nitrate (NO3) 10 Chesney Consulting