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27 April 2020 AdvancedGeo Project No. 20-5084 AnEmplopee Owned Company Page 13 of 15 RESIDENTIAL: The Hantzsche / Finnemore (Nr) equation for residential home application: Nr = IxNw (1-d) + RxNb = (I+R) Definitions.- Nr efinitions:Nr = The average concentration of nitrate-nitrogen in the recharged wastewater parts per million of nitrate-nitrogen. I = Volume rate of wastewater entering the soil averaged over the gross developed area (acres) in inches per year. The total wastewater volume for proposed project will be 150 gpd (existing system) + 150 gpd (proposed system) x 365 days of proposed operation _ (150 + 150) x 365 days - 7.48 gallons per cubic foot = 14,639 cubic feet of wastewater. Does not account for evapotranspiration likely to occur. NW = Total nitrogen concentration of wastewater at 45 mg/L-N based on the average discharge. Accounting for the loss of mg/L-N in the septic tank at 15% = 45-15%= 38.25 and the loss from the biomat at 10% 38.25 - 10% = 34.425 mg/L-N d = Fraction of nitrogen concentration removed from the wastewater due to denitrification within the soil (30 percent for clay loam soils). R = Estimated Deep percolation / average rainfall recharge rate per year: 3.12 inches. Nb = Background nitrate-nitrogen concentration of rainfall recharge: 1.0 mg/I. The Nb is an average value determined for San Joaquin County by the EHD. EXISTING HOME AND PROPOSED HOME CALCULATIONS (COMBINED): Nr = I x Nw (1-d)+ R x Nb _ (I+R)Assumptions: I = 109,500 gallons = 14,639 cubic feet wastewater _ [(2.01 acres x 43,560 feet') _ 12 inches] = 2.00 inches/year NW = 34.425 mg/L-N d = 30 percent denitrification R = 3.12 inches/year Nb = 1.0 milligram per liter Nr = [2.00 inches/year x 34.425 mg/L-N (1-0.30)] + (3.12 inches/year x 1.0 milligram per liter) _ (2.00 inches/year + 3.12 inches/year) Nr = 51.31 = 5.12 = 10.0 Nr = 10.0 ppm nitrogen (NO3_N)