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LOGE 1844: Farris NLS Addendum Page 5 <br /> March 5, 2019 <br /> ground-water model covering parts of San Joaquin County, northern Stanislaus <br /> County, and southern Sacramento County. In the model, percolating recharge <br /> waters throughout the Eastern San Joaquin subbasin (portion of the model area) <br /> were evaluated; a value of 650,000 acre-feet was used for ground-water <br /> recharge throughout the subbasin. This value was derived after numerous model <br /> calibration runs. By dividing 650,000 acre-feet by the total acreage of the <br /> subbasin (772,376 acres), and converting to inches, a regional rate of recharge <br /> from percolating waters throughout the subbasin was found to be 10.1 inches per <br /> year. This value should be viewed as an average for the subbasin area. <br /> Calculated Rates of Recharge from Percolating Waters for Project Site <br /> The following table summarizes the values for rate of recharge from percolating waters <br /> obtained from the methods discussed above for the project Site: <br /> Table 2. Rates of Recharge from Percolating Waters for Site <br /> Method Result (in./yr.) Comment <br /> 100 Percent Rainfall 12.21 Likely overestimates recharge from <br /> percolating waters <br /> Evapotranspiration Reduction 2.43 Likely underestimates recharge from <br /> percolating waters <br /> Reduced Rainfall 9.2 Selected value <br /> Regional Recharge from Percolating Waters 10.1 Regional average; similar to selected <br /> value <br /> For this Site, the average rate of 9.2 inches per year of recharge from percolating <br /> waters obtained through the reduced rainfall method has been selected. This value <br /> compares favorably with the predicted rate of recharge from percolating waters <br /> throughout the Eastern San Joaquin subbasin of 10.1 inches. The other two values <br /> most likely over- and under-estimate percolating recharge, as can be seen by <br /> comparison with the regional value generated by the subbasin model. <br /> The nitrate concentration of the recharge waters was estimated to be 1 mg/L-N <br /> (Hantzsche and Finnemore). <br /> Quantity and Quality of Domestic Wastewater <br /> Ms. Farris plans to construct a three-bedroom home on the Site. The land is currently <br /> vacant. <br /> Crites and Tchobanoglous (1998) list a typical flow rate of 50 to 70 gallons per person <br /> per day for an individual residence. The San Joaquin County Enviromental Health <br /> Department has indicated that maximum flow and double occupancy within each <br />