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LOGE 1726: Phillips/Michael David NLS Addendum Page 5 September 20, 2017 • Contribution of Rainfall An estimate of the quantity and quality of rainfall was required for the nitrate loading analysis. The Hantzsche and Finnemore method utilizes the "average recharge rate of rainfall'in calculating potential nitrate impacts to the aquifer. Not all rainfall will percolate into the aquifer,- evapotranspiration, the sum of evaporation and plant transpiration, will significantly reduce percolating effluent, especially in summer months. Rainfall recharge (deep percolation of rain) is a significant factor in the nitrate loading estimate; however, data on rainfall recharge rates are not widely available. Hantzsche and Finnemore present average rainfall versus estimated rainfall recharge data for three locations in California: Table 2: Rainfall Data Cited by Hantzsche and Finnemore, 1992 Bolinas Mesa Area Chico Area Baywood/Los Osos Average rainfall 30.9 22.5 20.0 (in/yr) Estimated rainfall 14.4 16.8 12.0 recharge (in/yr) Rainfall recharge as 46.6% 74.7% 60.0% percentage of • average rainfall* *Calculated by Live Oak In these locations, the rainfall recharge is calculated to be 46.6, 60.0, and 74.7 percent of average rainfall. The Chico area is the most similar geologically to the current project area. For the purpose of this report, Live Oak has selected 75 percent of rainfall to represent the estimated rainfall recharge for the project area. Rainfall data for the Lodi area was obtained from the Western Regional Climate Center. The Lodi station (045032), the closest station to the Site, reports the average total annual precipitation from January 1893 through January 2015 to be 17.24 inches. By assuming 75 percent of this precipitation percolates to the aquifer, the value of 12.93 inches average recharge of rainfall is obtained. The nitrate concentration of rainfall was estimated to be 1 mg/L-N (Hantzsche and Finnemore, 1992). Quantity and Quality of Domestic Wastewater The estimated sewage flow rates for various uses are available from a number of references. The uses presented below were guided by the San Joaquin County On-Site Wastewater Disposal Standards (2003), Crites and Tchobanoglous (1998), and EPA (1980). The references indicate that 13 gallons for each employee is typical for an office worker, 3 gallons is typical for a bar customer, and 9 gallons is typical for a restaurant customer; these rates were used for the tasting room, winery, and caf6 (Crites and Tchobanoglous, 1998). For the special event customer, an intermediate flow rate of 5 gallons per customer was selected.