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Nitrate was detected in the May 17, 2019 sample at a concentration of 0.4 mg/L-N, in the May 19, 2019 sample at a concentration of 0.2 mg/L-N, and in the March 16, 2020 sample at a concentration of 0.2 mg/L. Live Oak then averaged the concentrations of the three samples, for a value of 0.27 mg/L-N to represent the nitrate concentration of rain. The analytical reports are attached as Appendix 6. Because the San Joaquin County Environmental Health Department has requested that local and recent data be utilized wherever possible, the concentration of the Lodi rainwater been selected for use in the nitrate loading calculation. Quantity and Quality of Domestic Wastewater Mr. Ackerman indicated that the existing home has two bedrooms, and the existing apartment has one bedroom. Crites and Tchobanoglous (1998) list a typical flow rate of 50 to 70 gallons per person per day for an individual residence. In the past, San Joaquin County Environmental Health Department has requested that the flow rate be calculated as 140 gallons per bedroom per day to reflect maximum usage. On March 4, 2020, however, Michael Kith, Lead Registered Environmental Health Specialist at the San Joaquin County Environmental Health Department, stated that he has conferred with Norman Hantzsche (author of the 1992 paper discussed previously), and they have arrived at a new method to determine flow from residential sources. He indicated that wastewater flow from a single-family residence should be calculated as 100 gallons per day (gpd) for the first bedroom and 50 gpd for each additional bedroom; additional residences should be calculated in the same manner (personal communication, March 4, 2020). Using this method, the main house would contribute 150 gpd, and the apartment would contribute 100 gpd. The maximum daily flow for the Site is then estimated to be 250 gpd. A typical residential concentration of 35 mg/L of nitrate as N was selected for the proposed residence (Crites and Tchobanoglous, 1998). 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 On-Site Wastewater Treatment Systems Standards 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 20-15 Page 11