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The surface and near surface soils at the Site are reported by the USDA Web Soil <br /> Survey to be composed of Redding gravelly loam (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 /> Redding 0-7: Gravelly loam; SC, SC- <2 5.1 -6.5 0.6-2.0 Severe: <br /> gravelly loam, SM, GC, GM-GC cemented <br /> 2-8% slopes, 7-16: Gravelly loam, gravelly <2 5.1 -6.5 0.2 -0.6 pan <br /> 220. clay loam; CL, CL-ML, <br /> GC, GM-GC <br /> 16-22: Clay, clay loam; CH, <2 5.1 -6.5 <0.06 <br /> CL <br /> 22-60: Indurated --- --- --- <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 February 25, 2026, Live Oak excavated shallow and deep soil borings on the Site <br /> for the purpose of percolation testing. The borings were four inches in diameter, 1.84 <br /> and 7.64 feet deep, and were excavated by hand auger. The location of the borings is <br /> indicated on Plate 13. <br /> The soil in the borings was similar to that described by the Soil Survey. Sandy silt with <br /> clay was encountered to four feet below ground surface, followed by sandy clay to <br /> seven feet below ground surface, followed by clayey coarse sand to the full depth of the <br /> hole. The soil log is presented on Plate 14. <br /> Discussion of Soil Lithology <br /> Based on the soil observed in the borings, there appears to be limited potential for <br /> percolation in the shallow soil zone, but greater potential starting at around seven feet <br /> below ground surface. 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 /> Percolation Test <br /> A shallow and deep percolation test was conducted near the proposed septic disposal <br /> area for the new ADU. The soil borings discussed above were used for the percolation <br /> LOGE 2611 Page 5 <br />