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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 spring and fall of 2011 were the most recent available from this source. According to an analysis of these maps (Plates 5 and 6), ground water elevation ranges from approximately seven to 15 feet above mean sea level: ground water flows down to the north-northeast at a rate of approximately seven to 10 feet per mile in the vicinity of the Site. Given that the ground elevation of the Site is approximately 50 to 55 feet, based on the County ground water maps the depth to ground water below the Site is estimated to range between 35 to 47 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, 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. Several cattle facilities are located in the area. Live Oak reviewed the EHD's Water Well Data Table dated March 10, 2009 for nearby addresses that have been tested for nitrate and dibromochloropropane (DBCP). Five nearby wells were identified at addresses located within approximately 1.25 miles of the Site. Four of the wells had been tested for DBCP; it was detected in only one)of the four at a concentration of 0.27 pg/L. The Maximum Contaminant Level (MCL}-sit by the US EPA for DBCP is 0.2 ug/L. Nitrate as NO3 was detected in all five wells at,_ _ concentrations of 11.0 to 51.4 parts per million (ppm). The MCL for nitrate as NO3 is 45 ppm. On-Site Wells As indicated on the site m (P ate 3), three wells are located on the Si ovide irrigation water, while t third rovides both irrigation water and water to ttie sales office. Two well permit on file at the San Joaquin County Environmental Health Department for the S(te: • December 1977 permit for new irrigation well. This well appears to be located near the center of the Site. LOGE 1226 Page 3