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reasonably be required to remove this contaminant should it occur in drinking water. The Maximum Contaminant Level Goal (MCLG) for DBCP is zero. The laboratory analytical results are attached as Appendix 5 of this report. Soil Profile and Geologic Information The Site is depicted on the Preliminary geologic map of Cenozoic deposits of the Bellota Quadrangle, California (Marchand and Bartow, 1979). The Site is depicted within map units of the Riverbank formation upper unit and middle unit, both described as "arkosic alluvium forming Mokelumne River terraces and alluvial fan; chiefly sand; probably glacial outwash" (Plate 7). The surface and near surface soils located at the Site are reported by the USDA Web Soil Survey to be composed of San Joaquin loam, thick surface (Plate 8) (USDA, 2018). 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 Reaction ability absorption Symbol (in) Classification mmhos/cm pH (in/hr) fields San 0-12: Loam; CL-ML, ML <2 5.6-6.5 0.6-2.0 Severe: Joaquin 12-26: Sandy clay loam; SC <2 6.1-7.3 0.2-0.6 cemented loam, thick 26-35: Clay loam, clay; CL <2 6.1-7.8 <0.06 pan, peres surface, 0- 35-60: Indurated --- --- --- slowly 2% slopes 240. 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 December 12, 2018, Live Oak excavated a shallow soil boring in the proposed septic disposal area of the Site for the purpose of conducting a percolation test. The boring was four inches in diameter, 3.40 feet deep, and was excavated by hand auger (Table 2). On December 28, 2018, Ford Construction excavated a deep soil boring adjacent to the shallow boring; Live Oak observed the procedure and logged the soil. Because of extreme cemented soil conditions encountered, the deep boring was dug by an excavator to a depth of 22.48 feet. A four-inch perforated PVC pipe was installed in native soil at the side and bottom of the pit for use in the percolation test. The location of the boring is indicated on Plate 9. The soil in the borings was similar to, but sandier than, that described by the Soil Survey. Sandy clay with road base was encountered to a depth of one foot, followed by sandy clay to a depth of three feet, followed by cemented silty sand to a depth of 22 LOGE 1848 Page 5