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Soil Profile and Geologic Information <br /> The Site is depicted on the Geologic map of the San Francisco-San Jose quadrangle, <br /> California (Wagner, et al., 1991). The Site is depicted within a map unit of Holocene <br /> alluvial fan deposits (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 Vernalis clay loam (Plate 8) (USDA, <br /> 2018). 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 pH (in/hr) fields <br /> Capay Clay, 0-20: Clay; CH, CL <4 6.6 - 8.4 0.06 - 0.2 Severe: <br /> wet, 0-2% 20-44: Clay, silty clay: CH, CL <4 6.6 - 8.4 0-06 - 0.2 peres slowly <br /> slopes, 121 44-60: Silty clay loam, clay <4 6.6 -8.4 0.06 - 0.2 <br /> loam: CL <br /> Vernalis 0-9: Clay loam; CL <2 6.6 - 8.4 0.2 - 0.6 Severe: <br /> clay loam, 9-47: Loam, silt loam, clay <2 7.4 - 8.4 0.6 - 2.0 peres slowly <br /> wet, 0-2% loam; CL, CL-ML <br /> slopes, 47-60: Stratified sandy loam to <2 7.9 - 8.4 0.6 - 2.0 <br /> 269 clay loam; CL CL-ML <br /> Note: The table descriptions do not necessarily reflect site-specific soil properties. See description of the map unit for <br /> composition and behavior characteristics of the map unit. <br /> Soil Borings <br /> On December 11, 2018, Live Oak excavated shallow soil borings in the proposed septic <br /> disposal area and one hundred percent replacement area of the Site for the purpose of <br /> conducting percolation tests. The borings were four inches in diameter, 3.05 and 3.08 <br /> feet deep, and were excavated by hand auger (Table 2). The locations of the borings <br /> are indicated on Plate 9. <br /> The soil in the borings was similar to that described by the Soil Survey. Sandy clay was <br /> encountered to the full depth of each the hole. The soil log is presented on Plate 10. <br /> Discussion of Soil Lithology <br /> Based on the soil observed in the borings, there appears to be some potential for <br /> percolation. Generally speaking, sandy soils 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 1846 Page 4 <br />