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Sources of Nitrate <br /> Septic systems and dairies have been found to be the most significant sources of nitrate <br /> in ground water. Orchards that require fertilization in sandy soils are also a significant <br /> source of nitrate contamination in shallow or sandy aquifers in San Joaquin County. <br /> Contribution of Rainfall <br /> An estimate of the quantity and quality of rainfall was required for the nitrate loading <br /> analysis. The Hantzsche and Finnemore method utilizes the "average recharge rate of <br /> rainfall" in calculating potential nitrate impacts to the aquifer. Not all rainfall will <br /> percolate into the aquifer; evapotranspiration, the sum of evaporation and plant <br /> transpiration, will reduce percolating effluent, especially in summer months. <br /> Rainfall recharge (deep percolation of rain) is a significant factor in the nitrate loading <br /> estimate; however, data on rainfall recharge rates are not widely available. For the <br /> Chico area, Hantzsche and Finnemore present an average rainfall of 22.5 inches per <br /> year and an estimated rainfall recharge of 16.8 inches per year; the recharge rate is <br /> calculated to be 75 percent of the average rainfall. Because the Chico area is similar <br /> geologically to San Joaquin County, for the purpose of this report Live Oak has selected <br /> 75 percent of rainfall to represent the estimated rainfall recharge for the project area. <br /> Rainfall data for the north Lodi area was obtained from the Western Regional Climate <br /> Center. The Lodi station (045032), the closest active station to the Site, reports the <br /> average total annual precipitation from January of 1893 through January of 2015 to be <br /> 17.24 inches. By assuming 75 percent of this precipitation percolates to the aquifer, the <br /> value of 12.9 inches average recharge of rainfall is obtained. <br /> The nitrate concentration of rainfall was estimated to be 1 mg/L-N (Hantzsche and <br /> Finnemore). <br /> Quantity and Quality of Domestic Wastewater <br /> The proposed project is the construction of a new winery in three phases. According to <br /> the project application, two employees will work in the winery seven days per week, and <br /> two additional employees will work in the tasting room Thursday through Sunday; an <br /> estimated 20 customers per day are anticipated when the tasting room is open. An <br /> existing two-bedroom house is also located on the Site. <br /> LOGE 1841 Page 9 <br />