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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). Eight 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 detected in four of the eight at concentrations from 0.024 and 0.10 *ag/L. The Maximum Contaminant Level (MCL) set by the US EPA for DBCP is 0.2 pg/L; however, the MCL Goal (MCLG) is 0 µg/L. Nitrate as NO3 was detected in all eight wells at concentrations from 10.0 to 89.0 parts per million (ppm). The MCL for nitrate as NO3 is 45 ppm. On-Site Wells As indicated on the site map (Plate 3), one domestic well and one irrigation water well exist on the Site. Two well permits were on file at the San Joaquin County Environmental Health Department for the Site: • August 1978 permit for new irrigation well in almond orchard. (19642) • February 2006 permit for pump replacement at domestic well. (19654) The permits can be found in Appendix 4. Water Sample Live Oak collected a water sample from the irrigation well on December 18, 2013. The sample was to be analyzed for Nitrate and dibromochloropropane (DBCP) per San Joaquin County Environmental Health Department policy. As required by the laboratory, the sample was collected in a plastic container and two glass vials for nitrate and DBCP analysis, respectively. A trip blank was also utilized. The sample was placed on ice and transported under chain of custody to FGL Environmental, Stockton. Nitrate was detected at a concentration of 137 mg/L-NO3in the water sample. Nitrate is commonly detected in shallow ground water aquifers of the Central Valley. Application of fertilizers, livestock waste, and untreated septic tank waste can all contribute to nitrate in ground water. Nitrate is mobile and tends to accumulate in shallow ground LOGE 1328 Page 4