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LOGE 1847: Jhamat SS/NLS Addendum Page 4 March 6, 2019 Table 1. Estimate of Deep Percolation of Rainfall for N. Stockton, CA. Month Average Rain- Average Potential Annual Potential Fall (inches) Evapotranspiration Deep Percolation of (inches) Rain (inches) January 3.43 1.24 2.19 February 2.94 1.96 0.98 March 2.71 3.41 None April 1.31 5.10 None May 0.61 6.82 None June 0.15 7.80 None July 0.03 8.06 None August 0.04 7.13 None September 0.27 5.40 None October 0.93 3.72 None November 1.93 1.80 0.13 December 2.92 0.93 1.99 Totals 17.24 53.37 5.29 Notes: CIMIS evapotranspiration information at wwwcimis.water.ca.gov/cimis/for ETo Zone 12. Rainfall from Lodi station (045032). Closest active station to Site was selected. • Reduced Rainfall: For this method, rainfall levels from the closest rain station are multiplied by a percentage based on a reasonable assumption from the literature. Because the Hantzsche and Finnemore model utilized a value of approximately 75 percent rainfall as the rate of recharge from percolating waters in the Chico area, that value is applied to local rainfall in the project area. The San Joaquin County Environmental Health Department recommended this approach in 2017, with the understanding that it would better characterize recharge within the County (personal communication with Rodney Estrada, Lead REHS, January 6, 2017). As discussed above, Lodi station (045032), the closest active station to the Site, reports the average total annual precipitation from January 1893 through January 2015 to be 17.24 inches (Table 1). Assuming 75 percent of this precipitation percolates to the aquifer (as Hantzsche and Finnemore did in Chico), the rate of recharge from percolating waters is calculated to be an average of 12.9 inches per year.