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The surface and near surface soils located at the Site are reported by the USDA Web <br /> Soil Survey to be composed of Hollenbeck silty clay (USDA, 2026) (Plate 12). The table <br /> below presents some selected properties of this soil type: <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 (in) Class <br /> Reaction ability absorption <br /> Symbol Classification mmhos/cm pH (in/hr) fields <br /> Hollenbeck 0-10 Silty clay; CH, CL <2 6.6-8.4 0.06-0.2 Severe: <br /> silty clay, 10-37 Clay, silty clay; CH, CL <2 6.6-8.4 0.06-02 peres slowly <br /> 0-2% slopes, 37-42 Silty clay loam, clay <2 6.6-8.4 0.2-0.6 <br /> 173 loam; CL <br /> 42-60 Cemented --- --- --- <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 April 27, 2026, Live Oak excavated a shallow soil boring on the Site for the purpose <br /> of percolation testing. The boring was four inches in diameter, 3.24 feet deep, and was <br /> excavated by hand auger. The location of the boring is indicated on Plate 13. <br /> The soil in the boring was similar to, though more organic than, that described by the <br /> Soil Survey. Organic, silty clay was encountered to a depth of three feet below ground <br /> surface, followed by clay to the full depth of the boring. The soil log is presented on <br /> Plate 14. <br /> Discussion of Soil Lithology <br /> Based on the soil observed in the boring, there appears to be limited potential for <br /> percolation in the shallow soil zone. Sandy soils generally have a much greater <br /> potential for percolation than fine-grained or cemented soils. However, a percolation <br /> test is the only accepted method for determining the suitability of the soils for a septic <br /> disposal area. Percolation test results are discussed in the following section. <br /> Percolation Test <br /> A shallow percolation test was conducted near the proposed septic disposal area for the <br /> new ADU. The soil boring discussed above was used for the percolation test hole. <br /> Percolation test procedures conformed to San Joaquin County Environmental Health <br /> Department policy. <br /> LOGE 2620 Page 5 <br />