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• Soil Profile and Geologic Information The Site is mapped on the Geologic Map of the San Francisco-San Jose Quadrangle (Wagner, et. al., 1991). It is depicted within a map unit of the Riverbank formation (Plate 7). The surface and near surface soils located at the Site are reported by the Web Soil Survey (USDA, 2018) to be composed of Exeter sandy loam and Madera sandy loam (Plate 8). The table below presents some selected properties of these soils: Table 1. Selected Properties of On-Site Soils (USDA, 1992) Soil Name Depth Unified Soil Salinity Soil Perme- Septic tank and Map (in) Classification mmhos/cm Reaction ability absorption Symbol pH (in/hr) fields Exeter 0-26: Sandy loam; SM, SC- <2 6.1-7.3 0.6-2.0 Severe: sandy loam, SM cemented 0-2% 26-33: Sandy clay loam, clay <2 6.6-7.8 0.6-2.0 pan, peres slopes, 157 loam, loam; CL, SC slowly 33-60: Indurated --- --- Madera 0-19 Sandy loam; SM <2 5.6-7.3 2.0-6.0 Severe: sandy loam, 19-23 Sandy clay loam; SC <2 6.1-7.3 0.2-0.6 cemented • 0-2% 23-29 Clay, clay loam; CL, CH, <2 6.6-8.4 <0.06 pan, peres slopes, 193. Sc slowly. 29-60 Indurated <2 --- --- Note: The table descriptions do not necessarily reflect site-specific soil properties. See description of the map unit for composition and behavior characteristics of the map unit. Soil Borings In September and October of 2018, Live Oak excavated shallow soil borings on three proposed parcels parcel of the Site, as well as shallow and deep borings on the final proposed parcel, for the purpose of conducting percolation tests. The borings were four inches in diameter, 3.02, 3.02, 3.35, 3.36, and 8.76 feet deep, and were excavated by hand auger (Table 2). The locations of the borings are indicated on Plate 9. The soil in the borings was similar overall to that described by the Soil Survey, but was found to vary substantially across the Site. In boring P1, silty sand was encountered to approximately 2.5 feet below ground surface, followed by cemented sand with silt to the full extent of the hole. In boring P2, sandy clay was encountered to approximately 1.6 feet below ground surface, followed by cemented, silty sand to the full depth of the hole. In boring P3, clayey, partially cemented sand was encountered to approximately one foot below ground surface, followed by cemented, sandy clay to approximately 3.5 feet, followed by silty sand to approximately 4.8 feet, followed by clayey sand to the full depth of the hole. In boring P4, sandy clay was encountered to approximately 2.5 feet below • LOGE 1809 Page 4