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Soil Suitability / Nitrate Loading Study Cherokee Memorial Park Vineyard Chapel Addition Ŷ Lodi, California March 5, 2021 Ŷ Terracon Project No. NA207102 Responsive Ŷ Resourceful Ŷ Reliable 11 Gallons per day (GPD). Gallons per 8 hour day (GPD8). Gallons per 9 hour day (GPD9). Employee Effluent 13 gpd / 8 hours per day = 1.625 gallons per hour x 9 hours = 14.625 gpd (GPD9) Visitor Effluent 2 gpd. Visitors are assumed to be onsite less than 8 hours per day. Special Events Effluent (600 events per year / 365 days per year = 1.64 events per day x 40 visitors per day = 65.6) The maximum daily flow rate for the existing facility operations is approximately 1,316 gpd. The proposed Vineyard Chapel addition is anticipated to add approximately 525 gallons of effluent per day for a combined maximum daily flow rate of approximately 1,841 gpd for the facility. 1.4 Groundwater Information 1.4.1 Groundwater Depth and Gradient In 2014, groundwater was not encountered within our borings which were drilled between 3.05 and 3.07 feet bgs (Section 1.1). Based on a review of Well Completion Report for the onsite well located on the northern portion of the site, groundwater was encountered at 70 feet bgs in the year 2016. According to the California Department of Water Resources Sustainable Groundwater Management Act (SMGA)Data Viewer, in Fall 2019 depth to groundwater was reported between approximately 80 to 90 feet bgs. In Spring 2020 depth to groundwater was reported between 60 to 70 feet bgs. Groundwater flow direction was reported to the southeast. The groundwater flow direction and the depth to shallow, unconfined groundwater, if present, would likely vary depending upon seasonal variations in rainfall and other hydrogeological features. Without the benefit of on-site groundwater monitoring wells surveyed to a datum, groundwater depth and flow direction beneath the site cannot be directly ascertained. 1.4.2 Potential Groundwater Contamination Issues Potential groundwater contamination can occur from a number of sources including historical petroleum hydrocarbon use, agricultural activities, dairies, septic systems, and storm water infiltration. As per EHD requirements nitrate as N and 1,2-dibromo-3-chloropropane (DBCP) have been included as part of the SSS discussion. Identifying potential groundwater contamination other than nitrates and DBCP is beyond the scope of work for this report. The presence of nitrates is not uncommon in shallow groundwater aquifers in San Joaquin County and other parts of the Central Valley. Nitrate in groundwater occurs as a result of the application of fertilizers, livestock waste, and untreated septic tank waste. Nitrate is mobile and often accumulates in the shallow groundwater zones. In the early 1900s, natural levels of nitrate in groundwater were measured in forty-three (43) wells throughout the Sacramento Valley by Kirk Bryan (1923). It was thought that groundwater at that time was close to “natural” conditions. Based on the work by Bryan, it is estimated that under “natural” conditions, groundwater concentration containing nitrate is no more than about 13.5