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April 17, 2019 BGG Job No. G001.05 Conservation District(SJCFCWCD)to determine the ground water levels near the Site. Recent data indicates that ground water at the site is approximately 4Qto 45 fe&t below ground surface(bgs)and ground water flows predominantly toward the northeast. Previous subsurface explorations at the Delicato Winery facility have encountered ground water between 35 to 40 feet bgs. A detailed evaluation of these and other factors,which may be responsible forgroundaater fT'uctuations,was beyond the scope of this study. Potential Ground Water Contamination Issues The Soil Suitability Study is not intended to serve as an investigation into groundwater contamination sources, and no such investigation was conducted. Many sources can contribute to ground water contamination, including underground storage tank leaks, agricultural applications, dairy activities, septic systems, and storm water infiltration. Agricultural activities and the use of septic systems in the area are known groundwater contamination sources with the potential for impact to the site. BGG reviewed the SJC EHD Water Well Data Table dated March 10,2009 for nearby addresses that have been tested for nitrate and dibromochloropropane (DBCP), identified groundwater contaminants in San Joaquin County. The Maximum Contaminant Level(MCL)established by the US EPA for nitrate as NO3 is 45 mg/L(10 mg/L-N)and the MCL for DBCP is 0.2 µg/L. For wells identified within approximately 1 mile of the subject site, the following summarizes the reported results: �� • Nitrate was detected in the wells identified, at concentrations of 25.0 to 48.0 mg/L-NO3. f-- • DBCP was not detected. Vr Wells Onsite �I-1p C No wells are currently located at the guard station site. No well permit wsr ere identified for the Site from among files at the San Joaquin County Environmental Health Department. Water Sample A water sample was not collected for this study. SOIL PROFILE AND GEOLOGIC SETTING The site is shown on the Geologic map of the San Francisco-San Jose quadrangle of California (Wagner, et al., 1991)to be underlain by alluvial fan deposits of the holocene age. According to the USDA Web Soil Survey,the site is mapped as being mantled by the Veritas Fine Sandy Loam soil series. This soil series in the upper 4 or 5 feet is reported to have 100%passing the No.4 sieve(sand-sized particles),contain 35 to 50 percent fines(silt-and clay-sized particles),and is nonplastic with a Plasticity Index of 10 or less. Cemented hardpan is reported at a depth of 4 to 5 feet. The saturated hydraulic conductivity of the soil series varies between 2 to 6 inches per hour, with underlying hardpan at depth that is nearly impermeable. The Web Soil Survey report is contained in Appendix A. BAEZ GEOTECHNICAL GROUP Soil Suitability Study and Nitrate Loading Study-DFV Guard Station Page 3