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February 24, 2020 BGG Job No. G123.02 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 Honcut sandy loam, Manteca fine sandy loam, and Veritas fine sandy loam soil series. These soil series in the upper 5 to 6 feet are reported to have 100%passing the No.4 sieve(sand-sized particles),contain 10 to 50 percent fines(silt-and clay-sized particles),and are nonplastic with a Plasticity Index of 10 or less. Cemented hardpan is reported between depths between 2 to 6 feet. The saturated hydraulic conductivity of the soil series varies between 2 to 6 inches per hour, with hardpan lenses that are reported as nearly impermeable. The Web Soil Survey report is contained in Appendix C. Soil Borings and Test Pits On January 22,2020,we performed a percolation test in the area of the proposed septic system leach field,as shown on Plate 2,Site Plan. Percolation testing was performed in accordance with current San Joaquin County Environmental Health Department percolating testing procedures; a permit was obtained prior to testing and a SJCEHD inspector was present for the final 30 minutes of the test to verify the procedures followed and the rate obtained. The results of the percolation test are contained in Appendix A. A record of the SJCEHD permit obtained is contained in Appendix B. On September 28,2019,BGG conducted a field exploration in the site vicinity,which consisted of excavating three test pits to depths of up to 5%2-feet below the ground surface (bgs), in the approximate locations shown on Plate 2, Site Plan. The test pits were excavated using a CAT 303.5E2 excavator and the soil was sampled with manually driven tube samplers. Materials encountered in the test pits were visually classified in the field and logs were recorded. The test pit logs showing soil classification and descriptions are contained in Appendix D. Based upon our field explorations, the general soil profile at the site can be characterized as a sequence of predominantly sandy and silty soils. The upper foot of soil consists of light to medium brown, loose to dense silty sand. Below the surface soil layer is 4 to 5 feet of brown and gray, medium dense to dense, silty sand to sand with silt which is occasionally cemented as hardpan. More detailed information of materials encountered in the exploratory test pits is included in the logs in Appendix D. Discussion of Soil Lithology Based on the soil observed in the test pits percolation test hole, there appears to be potential for percolation. Sandy soils generally have a greater potential for percolation than fine-grained (silts and clays)or cemented soils. Percolation testing is discussed in the following section. Percolation Testing Procedure Field percolation testing has been performed at the site in accordance with current SJCEHD percolation testing procedures. On January 22, 2020,we performed a percolation test in the area of the proposed winery septic system leach field,as shown on Plate 2, Site Plan.24-hours prior to testing,a manually powered auger was used to drill a 7-inch diameter boring to a depth of 41-inches bgs. The soils encountered were classified and logged,and approximately 2-inches of clean pea gravel was placed in the bottom of the boring. About 18-inches (vertically) of water was poured into the borehole and BAEZ GEOTECHNICAL GROUP Soil Suitability Study and Nitrate Loading Study-Zinc Nouse Winery Page 4