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Soil Profile and Geologic Information <br />The Site is depicted on the Preliminary geologic map showing Quaternary deposits of <br />the Lodi quadrangle, California (Marchand and Atwater, 1979). The Site is depicted <br />within map units of the Modesto formation lower member (alluvial deposits from the <br />Mokelumne River) and Modesto formation upper member (foothill -derived alluvial silt, <br />clay, and minor sand) (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 Jacktone clay (Plate 9) (USDA, 2022). The table below <br />presents some selected properties of this soil: <br />Table 1. Selected Properties of On -Site Soils (USDA, 1992) <br />Soil Name <br />Depth <br />Unified Soil <br />Salinity <br />Soil <br />Perme- <br />Septic tank <br />and Map <br />(in) <br />Classification <br />mmhos/cm <br />Reaction <br />ability <br />absorption <br />Symbol <br />y <br />pH <br />(in/hr) <br />fields <br />Jacktone <br />0-22 <br />Clay; CL, CH <br /><2 <br />6.6-8.4 <br />0.06-0.2 <br />Severe: <br />clay, 0-2% <br />22-34 <br />Clay loam, clay, silty <br /><2 <br />7.9-9.0 <br />0.06-0.2 <br />cemented <br />slopes, <br />clay; CL, CH <br />pan, peres <br />180 <br />34-37 <br />Indurated <br />--- <br />--- <br />--- <br />slowly <br />37-46 <br />Loam, clay loam; CL- <br /><2 <br />7.9-9.0 <br />0.2-0.6 <br />ML, CL <br />46-60 <br />Cemented <br />--- <br />--- <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 July 26, 2022, Live Oak excavated a shallow boring on the Site for the purpose of <br />conducting a percolation test. In consultation with Mr. Judge, a location where a small <br />office/shop/storage building could be constructed in the future was selected. The boring <br />was four inches in diameter, 2.50 feet deep, and was excavated by hand auger (Table <br />2). The location of the boring is indicated on Plate 10. <br />The soil in the boring was sandier and less clayey than that described by the Soil <br />Survey. Sandy silt was encountered to the full depth of the hole. The soil log is <br />presented on Plate 11. <br />Discussion of Soil Lithology <br />Based on the soil observed in the boring, there appears to be good 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 />LOGE 2236 Page 5 <br />