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Table 1. Selected Properties of On-Site Soils (USDA, 1992) <br /> Soil Name Depth Unified Soil Salinity Soil Perme- Septic tank <br /> and Map /cm Reaction ability absorption <br /> Symbol (in) Classification mmhos 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 /> 8-30% 7-16: Gravelly loam, gravelly <2 5.1 - 6.5 0.2 - 0.6 pan <br /> slopes, clay loam; CL, CL-ML, <br /> 221 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 May 4, 2026, Live Oak excavated a shallow soil boring on the Site for the purpose of <br /> percolation testing. The shallow boring was four inches in diameter, 1.57 feet deep, and <br /> was excavated by hand auger. Based on preliminary percolation test results in the <br /> shallow soil boring, Central Valley Septic Services was retained to excavate a deep <br /> boring as well; this boring was drilled on June 1, 2026 with a Spiradrill LHD 50. The deep <br /> boring was 12 inches in diameter and 24.87 feet deep. 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. Gravelly silt <br /> was encountered to 1 foot below ground surface, followed by silty gravel with sand to <br /> approximately 9 feet, followed by sandy gravel with silt to approximately 15 feet, <br /> followed by gray clay to approximately 20 feet, followed by sandy silt to the full depth of <br /> the 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 some potential in the deep soil zone. Sandy <br /> soils generally have a much greater potential for percolation than fine-grained or <br /> cemented soils. However, a percolation test is the only accepted method for <br /> determining the suitability of the soils for a septic disposal area. Percolation test results <br /> are discussed in the following section. <br /> Percolation Test <br /> A shallow and deep percolation test was conducted near the proposed septic disposal <br /> areas for the new homes. The soil borings discussed above were used for the <br /> LOGE 2622 Page 5 <br />