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The surface and near surface soils located at the Site are reported by the USDA Web Soil Survey to be composed of Devries sandy loam, drained, 0 to 2 percent slopes (Plate 12) (USDA, 2013). The table below presents some selected properties of this soil.. Table 1. Selected Properties of On-Site Soils (USDA, 1992) Soil Name Depth Unified Soil Salinity Soil Perme- Septic tank and Map (in) Class Reaction ability absorption Symbol Classification mmhos/cm pH (in/hr) fields Devries 0-13 Sandy loam; SM <2 6.6-8.4 2.0-6.0 Severe: sandy loam, 13-28 Sandy loam, fine sandy <2 6.6-8.4 2.0-6.0 Cemented drained, loam; SM Pan 0-2% 28-80 Indurated --- --- --- slopes, 149 Note: The table descriptions do not necessarily reflect site-specific soil properties. * See description of the map unit for composition and behavior characteristics of the map unit. Soil Borings On March 22 and 24, 2016, Live Oak excavated shallow and deep soil borings on the Site for the purpose of conducting percolation tests. The borings were four inches in diameter, 3.30 and 11.50 feet deep, and were excavated by hand auger. The location of the borings, near the septic disposal area of the church, is indicated on Plate 13. The current project includes an expansion of the existing church septic system; the 2016 percolation test was conducted within 100 feet of the expansion area. The soil in the borings was within the range of what would be anticipated based on the Soil Survey data reviewed. At the percolation test location, silty sand was encountered to a depth of nine feet, followed by fine to medium sand to the full depth of the boring. The log for the soil borings is presented in Plate 14. Discussion of Soil Lithology Based on the soil observed in the borings, there appears to be moderate potential for percolation of the surface soils, and good potential for percolation of the deeper soils. Sandy soils generally have a much greater potential for percolation than fine-grained or cemented soils. However, a percolation test is the only accepted method for determining the suitability of the soils for a septic disposal area. Percolation test results are discussed in the following section. Percolation Test One shallow and one deep percolation test were conducted on the Site; the soil borings discussed above were used for the percolation test holes (Plate 13). Percolation test procedures conformed to San Joaquin County Environmental Health Department policy. LOGE 1917 Page 6