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paper, only "average recharge rate of rainfall" was considered. For the Chico area, Hantzsche and Finnemore present an average rainfall of 22.5 inches per year and an estimated recharge of 16.8 inches per year. Based on San Joaquin County Environmental Health Department policy (personal communication, March 18, 2019), the recharge input for the Hantzsche and Finnemore equation should be derived from average monthly precipitation of rainfall and evapotranspiration rates for the area; the data should be obtained from the California Irrigation Management Information System (CIMIS), preferably from stations located within San Joaquin County. Recharge is calculated by first determining whether the average monthly precipitation exceeds average monthly potential evapotranspiration. If so, then the difference is the percolating recharge water into the aquifer. Runoff and stream infiltration drainage are not factored into the calculation. This approach likely under-estimates recharge to the aquifer and, consequently, over-estimates nitrate loading. For the project Site, the local percolation and evapotranspiration rates are presented in Plate 12. The Site is located closest to the CIMIS Station at Staten Island (station 242). Data for the Staten Island station were available for the past three years; based on the calculation shown, the estimated rate of recharge from percolating waters for the Staten Island station is determined to be 12.60 inches. A statistical error of 49 percent is associated with this value. The nitrate concentration of the recharge waters was estimated to be 1 mg/L-N (Hantzsche and Finnemore). Quantity and Quality of Domestic Wastewater According to Mr. Brum, the proposed new home will be four bedrooms in size. Crites and Tchobanoglous (1998) list a typical flow rate of 50 to 70 gallons per person per day for an individual residence. The San Joaquin County Enviromental Health Department has indicated that maximum flow and double occupancy within each bedroom should be considered for the nitrate loading assessment; as a result, a value of 140 gallons per bedroom per day has been selected (personal communication, January 6, 2017). The estimated flow values discussed here should not be used for the design and sizing of the septic system. The design and sizing of the septic system should utilize the San Joaquin County Environmental Health Department's On-Site Wastewater Treatment Systems Standards (2017), which incorporate peak and surge flow factors. The estimates used in the On-Site Wastewater Treatment Systems Standards may be greater than those discussed here. LOGE 1918 Page 6