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Soil Profile and Geologic Information <br /> The Site is depicted on the Preliminary Geologic map of Cenozoic Deposits of the <br /> Bellota Quadrangle, California (Marchand and Bartow, 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 terraces and alluvial fan; chiefly sand with <br /> minor gravel and silt; 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 Tokay fine sandy loam, 0 to 2 percent slopes (Plate 8) <br /> (USDA, 2013). The table below presents some selected properties of this soil: <br /> Table 1. Selected Properties of Onsite Soils(USDA, 1992) <br /> Soil Name Depth Unified Soil Salinity soil Perme- Septic tank <br /> and Map (in) Classification mmhoslcm Reaction ability absorption <br /> Symbol pH (In/hr) fields <br /> Tokay fine 0-19 Fine sandy loam; SM <2 6.1 -7.8 2.0-6.0 Slight <br /> sandy loam, 19-45 Fine sandy loam, sandy <2 6.1 -7.8 2.0-6.0 <br /> 0-2% loam; SM <br /> slopes, 256. 45-60 Fine sandy loam, sandy <2 6.1 -8.4 2.0-6.0 <br /> loam, coarse sandy <br /> loam; SM <br /> Note:The table descriptions do not necessarily retied 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 February 20, 2013, 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, 3.25 C5 yr s) <br /> feet deep, and was excavated by hand auger. The location of the boring is indicated on l <br /> Plate 9. <br /> The soil in the boring was within the range of what would be anticipated based on the <br /> Soil Survey data reviewed; sandy silt was observed the entire depth of the boring. The (5-3) <br /> log for the soil boring is presented in Plate 10. <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 1301 Page 5 <br />