SR0081894 SSNL - Laserfiche WebLink

Home Browse Search

collected in a clean, dry, stainless steel bowl, then decanted into a plastic container and placed on ice for transport. Nitrate was detected in the May 17 sample at a concentration of 0.4 mg/L-N and in the May 19 sample at a concentration of 0.2 mg/L-N. The laboratory analytical results are attached as Appendix 6 of this report. Live Oak then averaged the concentrations of the two samples, for a value of 0.3 mg/L-N to represent the nitrate concentration of rain. 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 The Mussis have no plans to develop the Site, and there are currently no structures on the Site. Based on the assumption of the nitrate loading method that only septic systems should be considered for the calculation, the wastewater flow from the proposed future use of the Site will be zero. Nevertheless, for the purposes of this study, a theoretical five-bedroom house and three-bedroom second unit dwelling are assumed for each parcel. These are considered so that, should the Mussis at some point in the future decide to build on the land, nitrate loading will have been addressed. 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 Norm 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). The first theoretical house on each parcel will have five bedrooms, which would result in a flow value of 300 gpd using the new method. The second theoretical house will have three bedrooms, which would result in a flow value of 200 gpd using the new method. The maximum daily flow for each parcel is thus estimated to be 500 gpd. A typical residential concentration of 35 mg/L of nitrate as N was selected for the theoretical residences (Crites and Tchobanoglous, 1998). LOGE 20-08 Page 10