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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 2012 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 eight to 24 feet below mean sea level; ground water flows down to the west-northwest at a rate of approximately 6.7 to 8.3 feet per mile in the vicinity of the Site. 1 Given that the ground elevation of the Site is approximately 100 to 105 feet, based on J the County ground water maps the depth to ground water below the Site is estimated to range between 108 to 129 feet, depending on the season. 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. 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). Four nearby wells were identified at addresses located within approximately one mile of the Site. All of the wells had been tested for DBCP; it was not detected in any of the wells. The Maximum Contaminant Level (MCL) set by the US EPA for DBCP is 0.2 ug/L. Nitrate as NO3 was detected in all four wells at concentrations of 14.0 to 18.0 parts per million (ppm). The MCL for nitrate as NO3 is 45 ppm. On-Site Wells As indicated on the site map (Plate 3), two irrigation wells and one domestic well exist on the Site. An abandoned well is also located on the Site. Two well permits were on file at the San Joaquin County Environmental Health Department for the Site. The first permit, dated April 1975, is for pump repair at an irrigation well. A note on the second page of the permit indicates that "the abandoned well, if not put back into use within 5 years, will have to be properly sealed under a well permit from the San Joaquin Local Health District." The second permit, dated January 2012, is for pump replacement at the domestic well. LOGE 1307 Page 3