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No contribution from any irrigation or soil amendment is considered for the <br /> Hantzsche/Finnemore method. It is reasonably assumed that any irrigation or soil <br /> amendments would be applied at close to agronomic rates for a net balance of plant <br /> irrigation and nutrients. <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 Acampo area was obtained from the Western Regional Climate <br /> Center. The Elliott station (0450010), the closest active station to the Site, reports the <br /> • average total annual precipitation from July of 1926 through May of 2016 to be 18.27 <br /> inches. By assuming 75 percent of this precipitation percolates to the aquifer, the value <br /> of 13.7 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 /> Mr. Lenzi anticipates that the new property owners will wish to construct a three- or four- <br /> bedroom home on each new parcel of the Site. The existing house is not included in <br /> the analysis because it will be demolished. <br /> Crites and Tchobanoglous (1998) list a typical flow rate of 50 to 70 gallons per person <br /> per day for an individual residence. The San Joaquin County Enviromental Health <br /> Department has indicated that maximum flow and double occupancy within each <br /> bedroom should be considered for the nitrate loading assessment; as a result, a value <br /> of 140 gallons per bedroom per day has been selected (personal communication, <br /> January 6, 2017). <br /> The estimated flow values discussed here should not be used for the design and sizing <br /> of the septic system. The design and sizing of the septic system should utilize the San <br /> LOGE 1836 Page 7 <br />