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A y Soil Profile and Geolo is Information The Site can be found on the Geologic Map of California, San Jose sheet (Rogers, 1966). It is depicted within a map unit of Pleistocene nonmarine deposits (Plate 8). The surface and near surface soils located at the Site are reported by the USDA Web Soil Survey to be composed of Capay clay, wet, 0 to 2 percent slopes, and Vernalis clay loam, wet, 0 to 2 percent slopes (Plate 9) (USDA, 2009). 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 5alini Soil Perme- Septic tank and Map tY Reaction ability absorption Symbol (in) Classification mmhoslcm pH (in/hr) fields Capay Clay, 0-20: Clay; CH, CL <4 6,6-8.4 0.06 -0.2 Severe: wet, 0-2% 2044: Clay, silty clay: CH, CL <4 6.6- 8.4 0,06-0.2 peres slowly slopes, 121 44-60: Silty clay loam, clay <4 6.6- 8.4 0.06 -0.2 loam: CL Vernalis 0-9: Clay loam; CL <2 6.6-8.4 0.2- 0.6 Severe: clay loam, 9-47: Loam, silt loam, clay <2 7.4-8.4 0.6-2.0 peres slowly wet, 0-2% loam; CL, CL-ML slopes, 47-60: Stratified sandy loam to <2 7.9-8.4 0.6-2.0 269 clay loam; CL, CL-ML 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 On April 21, 2011, Live Oak excavated one shallow soil boring on each proposed parcel the Site (four borings total) for the purpose of conducting percolation tests. The borings were four inches in diameter, with depths of 3.28, 3.45, 3.23, and 3.50 feet. They were excavated by hand auger. The boring locations are indicated on Plate 2. The soil in the borings was similar to that described above by the Soil Survey; brown lean clay was observed to the maximum depth of the borings (3.5 feet). Cemented conditions were encountered at approximately 2.7 feet below ground surface. The log for the soil borings is presented in Plate 10. Discussion of Soil Lifhology Based on the soils observed in the borings, there appears to be moderate potential for percolation. Sandy soils generally have a much greater potential for percolation than fine-grained or cemented soils. However, a percolation test is the only accepted method for determining the suitability of the soils for a septic disposal area. Percolation test results are discussed in the following section. LOGE 1116 Page 5