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• Ground Water Information Depth and Gradient Live Oak reviewed ground-water elevation information available from the San Joaquin County Flood Control and Water Conservation District to determine the ground-water levels near the Site. Data from the fall of 2014 and spring of 2015 were the most recent available from this source (Plates 6 and 7). According to an analysis of these maps, the ground-water elevation is approximately 46 to 54 feet below mean sea level; the ground-water flow is to the northeast at a rate of approximately four to five feet per mile. Given that the ground elevation of the Site is approximately 55 feet above sea level, (y 1) based on the County ground water maps the depth to ground water below the Site is estimated to range between 101 to 109 feet. Potential Ground Water Contamination Issues The Soil Suitability Study is not intended to be an investigation into ground-water contamination sources, and no such investigation was conducted. Many sources can contribute to ground water contamination, including leaking underground storage tanks, agricultural activities, dairies and cattle ranches, septic systems, and storm water infiltration. Agricultural activities and the use of septic systems in the area are known • ground-water contamination sources with the potential to impact the Site. Live Oak reviewed the San Joaquin County Environmental Health Department's Water Well Data Table dated March 10, 2009 for nearby addresses that have been tested for nitrate and dibromochloropropane (DBCP). Three wells were identified at addresses within approximately one-quarter mile of the subject Site. All the wells had been tested for DBCP; it was not detected in any. All the wells had been tested for nitrate; it was detected in two of the wells at concentrations of 5.9 to 21.0 mg/L-NO3. The Maximum Contaminant Level (MCL) set by the US EPA for nitrate as NO3 is 45 mg/L (equivalent to 10 mg/L-N). The MCL for DBCP is 0.2 µg/L. On-Site Wells A domestic well and an irrigation well are located on the Site. One well permit was identified for the Site at the San Joaquin County Environmental Health Department. The permit, dated January 1983, was for a new domestic well. The notes indicate that water was previously pumped from the irrigation well to the storage tank in the water tower. This permit is included in Appendix 4 of this report. Water Sample Live Oak collected a water sample from the domestic well on the Site on January 31, i 2017. The sample was analyzed for nitrate and dibromochloropropane (DBCP) per San • Joaquin County Environmental Health Department policy. LOGE 1706 Page 3