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• Soil Profile and Geologic Information The Site is mapped on the Geologic map of California: San Jose Sheet (Rogers, 1966). It is depicted within a map unit of Pleistocene nonmarine deposits (Plate 7). The surface and near surface soils located at the Site are reported by the Web Soil Survey (USDA, 2016) to be composed of the San Joaquin complex (Plate 8). The table below presents some selected properties of this soil: 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 San Joaquin 0-16 Loam; CL-ML ML <2 5.6-6.5 0.6-2.0 Severe: complex, 16-26 Clay loam, clay; CL <2 6.1-7.8 <0.06 cemented 0-1% 26-60 Indurated pan, peres slopes, 241 slow) 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 May 23 through June 3, 2016, Live Oak excavated soil borings on the two proposed parcel of the Site for the purpose of conducting percolation tests. A shallow boring was excavated on Parcel 1; both shallow and deep borings were excavated on Parcel 2. The borings were four inches in diameter, 3.30, 3.40, and 14.50 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 to that described by the Soil Survey. At location P1, sandy clay was encountered to a depth of 2.5 feet, followed by clayey sand to the full depth of the boring (3.4 feet). At location P2, sandy clay was encountered to a depth of 10 feet, followed by clayey sand to a depth of 13 feet, followed by sandy clay to the full depth of the boring (14.50 feet). The soil logs are presented on Plates 10 and 11. Discussion of Soil Lithology Based on the soil observed in the borings, there appears to be moderate potential for percolation at the test locations. 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 1608 Page 4