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within a map unit of the Modesto formation upper member described as "foothill -derived <br />alluvial silt, clay and minor sand following distributaries across lower fans; abundant <br />volcanic detritus" (Plate 8). <br />The surface and near surface soils located at the Site are reported by the USDA Web <br />Soil Survey to be composed of Rioblancho clay loam, drained (Plate 9) (USDA, 2022). <br />The table below presents some selected properties of this soil. <br />Table 1. Selected Properties of On -Site Soils (USDA, 1992) <br />Soil Name Soil Perme- Septic tank <br />and Map Depth (in) Unified Soil Salinity Reaction ability absorption <br />Symbol Classification mmhos/cm pH (in/hr) fields <br />Rioblancho <br />0-16 <br />Clay loam; CL <2 <br />7.4-8.4 0.2-0.6 Severe: <br />clay loam, <br />16-28 <br />Loam, Clay loam; CL- <2 <br />7.4-8.4 0.2-0.6 cemented <br />drained, 0- <br />ML, CL <br />pan, peres <br />2% slopes, <br />28-39 <br />Sandy loam, loam, <2 <br />7.9-8.4 0.6-2.0 slowly <br />226 <br />silt loam; SC -SM, <br />SM, CL -ML, ML <br />39-80 <br />Cemented --- <br />--- --- <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 March 21, 2022, Live Oak excavated a shallow soil boring in the proposed septic <br />repair area of the Site for the purpose of conducting a percolation test. The boring was <br />four inches in diameter, 2.25 feet deep, and was excavated by hand auger. At the <br />request of Mr. Wert, Central Valley Septic was retained to drill a deep boring on the <br />same day. This boring was 6.74 feet deep, 12 inches in diameter, and was completed <br />with a Spiradrill LHD 50. Central Valley also completed a soil profile boring nearby to a <br />depth of 13.5 feet. <br />The location of the borings is indicated on Plate 10. <br />The soil in the boring was similar to, though sandier than, that described by the Soil <br />Survey. Sandy clay was encountered to three feet below ground surface (bgs), followed <br />by clayey silt to four feet, silt to six feet, and very fine sand with silt to the full depth of <br />the hole. <br />In the soil profile boring, the very fine sand with silt continued to eight feet, followed by <br />sandy silt to nine feet, fine sand with silt to 11 feet, and fine to coarse sand with silt to <br />13.5 feet bgs. The soil log is presented on Plate 11. <br />LOGE 2218 Page 6 <br />