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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 a map unit of the Modesto Formation upper member. The unit represents <br /> "arkosic alluvium forming Mokelumne River alluvial fan; chiefly sand, becoming finer- <br /> grained toward fan toe; probably glacial outwash" (Plate 7). <br /> The surface and near surface soils located at the Site are reported by the USDA Web <br /> Soil Survey to be composed of Acampo sandy loam, 0 to 2 percent slopes (Plate 8) <br /> (USDA, 2009). The table below presents some selected properties of this soil: <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) Reaction ability absorption <br /> Symbol Classification mmhos/cm PH (in/hr) fields <br /> Acampo 0-19: Sandy loam; SM <2 6.1 - 7.8 2.0- 6.0 Moderate: <br /> sandy loam, 19-47: Sandy loam, fine sandy <2 6.6- 8.4 2.0-6.0 cemented <br /> 0-2% loam, coarse sandy pan <br /> slopes, loam; SM <br /> 101 47-49: Indurated; --- --- --- <br /> 49-60: Cemented, -- --- --- <br /> Note:The table descriptions do not necessarily reflect site-specific soil properties. <br /> See description of the map unit for composition and behavior characteristics of the map unit. <br /> Soil Borings <br /> On August 24, 2011, Live Oak excavated one shallow soil boring on the Site for the <br /> purpose of conducting a percolation test. The boring was four inches in diameter, 3.15 <br /> feet deep, and was excavated by hand auger. The boring location is indicated on Plate <br /> 2. <br /> The soil in the boring was within the range of what would be anticipated based on the <br /> Soil Survey data reviewed; silt with fine sand was encountered to a depth of 2 feet, <br /> followed by sandy silt for the remainder of the boring. The log for the soil boring is <br /> presented in Plate 9. <br /> i a <br /> Discussion of Soil Lithology <br /> Based on the soils observed in the boring, there appears to be moderate potential for <br /> percolation. Sandy soils generally have a much greater potential for percolation than <br /> fine-grained or cemented soils. However, a percolation test is the only accepted <br /> method for determining the suitability of the soils for a septic disposal area. Percolation <br /> test results are discussed in the following section. <br /> LOGE 1124 Page 5 <br />