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Use Data dated February 20, 2019. According to the nitrate map (Plate 9), three wells within a half-mile radius of the subject Site have been tested for nitrate. Nitrate was detected in two of these wells at a concentration between 0.1 and 5.0 mg/L-N, and in the third at a concentration between 5.1 and 10.0 mg/L-N. According to the DBCP map (Plate 10), one well within a half-mile radius of the Site has been tested for DBCP; it was detected at a concentration between 0.01 and 0.2 ug/L. The Maximum Contaminant Level (MCL) set by the US EPA for nitrate is 10 mg/L-N; the MCL for DBCP is 0.2 ug/L. On-Site Wells Two domestic wells are currently located on the Site, one to serve the house and one to serve the nursery building. Two well permits were identified for the Site from among the files of the San Joaquin County Environmental Health Department: • November 2001 permit for new domestic well at new house (23601). • July 2004 permit for new domestic well (at the nursery). These permits have been included in Appendix 4 of this report. Water Sample Live Oak collected a water sample from the proposed wine cellar well on March 22, 2019. The sample was analyzed for nitrate and dibromochloropropane (DBCP) per San Joaquin County Environmental Health Department policy. Because of discrepancy between the test results and prior testing on the Site (see below), a second sample was collected from the same well on April 29, 2019 and analyzed for nitrate. As required by the laboratory, the first sample was collected in a plastic container and two glass vials for nitrate and DBCP analysis, respectively. Trip blanks were also utilized. The second sample was collected in a plastic container. The samples were placed on ice and transported under chain of custody to FGL Environmental, Stockton. Nitrate was detected in the first sample at a concentration of 12.1 mg/L-N; it was detected in the second sample at a concentration of 7.8 mg/L-N. DBCP was not detected in the water sample. The laboratory analytical results are attached in Appendix 5 of this report. Mr. Roddan indicated that the nursery well had not been run for several months prior to the March 22 sampling due to a wet winter. Irrigation from the well began in April. As a result, it is the opinion of Live Oak that the second water sample is more representative of typical water conditions on the Site. As part of a previous investigation of the Site, Live Oak collected a water sample from the domestic well at the house on July 12, 2017 (Live Oak, 2017). Nitrate was detected LOGE 1908 Page 4