Laserfiche WebLink
30 June 2022 AdvancedGeo <br /> Project No. 22-6900 An Employee-Owned Company <br /> Page 13 of 15 <br /> (acres) in inches per year. The total wastewater volume for proposed project will be <br /> 200 gpd (existing system) + 200 gpd (proposed system)x 365 days of proposed operation <br /> = 400 x 365 days = 7.48 gallons per cubic foot = 19,519 cubic feet of wastewater. Does <br /> not account for evapotranspiration likely to occur. <br /> NW = Total nitrogen concentration of wastewater at 45 mg/L-N based on the average <br /> discharge. Accounting for the loss of mg/L-N in the septic tank at 15% = 45-15%= 38.25 <br /> and the loss from the biomat at 10% 38.25 - 10% = 34.425 mg/L-N. <br /> d = Fraction of nitrogen concentration removed from the wastewater due to denitrification <br /> within the soil (30 percent for loamy soils). <br /> R = Estimated Deep percolation / average rainfall recharge rate per year: 2.99 inches. <br /> Nb = Background nitrate-nitrogen concentration of rainfall recharge: 1.0 mg/I. The Nb is <br /> an average value determined for San Joaquin County by the EHD. <br /> EXISTING AND PROPOSED HOME CALCULATIONS: <br /> Nr = I x Nw (1-d) + R x Nb = (I+R) <br /> Assumptions: <br /> = 146,000 gallons = 19,519 cubic feet wastewater - [(2.00 acres x 43,560 feet') - 12 <br /> inches] = 19,519 = 7,260 = 2.69 inches/year <br /> NW = 34.425 mg/L-N <br /> d = 30 percent denitrification <br /> R = 2.99 inches/year <br /> Nb = 1.0 milligram per liter <br /> Nr = [2.69 inches/year x 34.425 mg/L-N (1-0.30)] + (2.99 inches/year x 1.0 milligram per <br /> liter) _ (2.69 inches/year + 2.99 inches/year) <br /> Nr = 67.81 - 5.68 = 11 .93 <br /> Nr = 11 .93 ppm nitrogen (NO3_N) <br /> 9.7. IMPACT OF NITROGEN LOADING FROM SITE PROJECT TO <br /> DOWNGRADIENT WATER SOURCES <br /> The recharging of groundwater is the most likely potential feature that could impact future <br /> nitrogen loading. Since the subject property is flat, AGI does not anticipate percolating <br /> effluent will affect any nearby water sources. Based on the volume of wastewater to be <br /> generated and the depth to groundwater (150-160 feet bsg), the potential vertical <br /> migration would not likely degrade the local groundwater. A total of 11.93 ppm of <br /> additional nitrogen is estimated to be added to the site over the long term through <br />