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LOGE 1847: Jhamat SS/NLS Addendum Page 5 March 6, 2019 • Regional Recharge from Percolating Waters: In 2018, the Eastern San Joaquin Groundwater Authority (ESJGA) commissioned a comprehensive ground-water model covering parts of San Joaquin County, northern Stanislaus County, and southern Sacramento County. In the model, percolating recharge waters throughout the Eastern San Joaquin Subbasin (portion of the model area) were evaluated; a value of 650,000 acre-feet was used for ground-water recharge throughout the subbasin. This value was derived after numerous model calibration runs. By dividing 650,000 acre-feet by the total acreage of the subbasin (772,376 acres), and converting to inches, a regional rate of recharge from percolating waters throughout the subbasin was found to be 10.1 inches per year. This value should be viewed as an average for the subbasin area. Calculated Rates of Recharge from Percolating Waters for Project Site The following table summarizes the values for rate of recharge from percolating waters obtained from the methods discussed above for the project Site: Table 2. Rates of Recharge from Percolating Waters for Site Method Result(in./yr.) Comment 100 Percent Rainfall 17.24 Likely overestimates recharge from percolating waters Evapotranspiration Reduction 5.29 Likely underestimates recharge from percolating waters Reduced Rainfall 12.9 Selected value Regional Recharge from Percolating Waters 10.1 Regional average; similar to selected value For this Site, the average rate of 12.9 inches per year of recharge from percolating waters obtained through the reduced rainfall method has been selected. This value compares favorably with the predicted rate of recharge from percolating waters throughout the Eastern San Joaquin Subbasin of 10.1 inches. The other two values most likely over- and under-estimate percolating recharge, as can be seen by comparison with the regional value generated by the subbasin model. The nitrate concentration of the recharge waters was estimated to be 1 mg/L-N (Hantzsche and Finnemore). Quantity and Quality of Domestic Wastewater Mr. Jhamat indicated that the proposed house will have five bedrooms. The land is currently vacant.