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Soil Profile and Geologic Information <br /> The Site is mapped on the Geologic Map of California, San Jose sheet (Rogers, 1966). <br /> It is depicted within map units of recent Great Valley fan deposits and Pleistocene <br /> nonmarine material (Plate 7). <br /> The surface and near surface soils located at the Site are reported by the USDA Web <br /> Soil Survey to be composed of Capay clay and EI Solyo clay loam (Plate 8) (USDA, <br /> 2009). The table below presents some selected properties of these soils: <br /> Table 1. Selected Properties of On-Site Soils (USDA, 1992) <br /> Soil Name Depth Unified Soil Salinity Soil Perme- Septic tank <br /> and Map Reaction ability absorption <br /> Symbol (in) Classification mmhos/cm <br /> y pH (in/hr) fields <br /> Capay Clay, 0-20: Clay: CH, CL <2 6.6- 8.4 0.06 - 0.2 Severe: <br /> 0-2% 20-60: Clay, silty clay: CL, CH <2 6.6- 8.4 0,06 - 0.2 peres slowly <br /> slopes, 118 <br /> EI Solyo 0-10 Clay loam: ML, CL <2 6.6-7.8 0.2-0.6 Severe: <br /> clay loam, 10-60 Silty clay loam, silty <4 7.4-8.4 0.06-0.2 peres slowly <br /> 0-2% clay: ML, MH, CL, CH <br /> slopes, 156 <br /> Note: The table descriptions do not necessarily reflect site-specific soil properties. <br /> `See description of the map unit for composition and behavior characteristics of the map unit. <br /> Soil Borings <br /> On December 21, 2011, Live Oak excavated one shallow soil boring on the proposed <br /> homesite parcel of the Site for the purpose of conducting a percolation test. The boring <br /> was four inches in diameter, 3.20 feet deep, and was excavated by hand auger (Table <br /> 2). The location of the boring is indicated on Plate 9. <br /> The soil in the boring was similar to, though less clayey than, that described by the Soil <br /> Survey. Silt with fine sand was encountered to the full depth of the hole, partially <br /> cemented conditions were encountered. The log for the soil boring is presented in Plate <br /> 10. <br /> Discussion of Soil Lithology <br /> Based on the soil observed in the boring, there appears to be moderate potential for <br /> percolation in the test location. Sandy soils generally have a much greater potential for <br /> percolation than fine-grained or cemented soils. However, a percolation test is the only <br /> accepted method for determining the suitability of the soils for a septic disposal area. <br /> Percolation test results are discussed in the following section. <br /> LOGE 1134 Page 5 <br />