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• The laboratory analytical results are attached as Appendix 5 of this report. _Soil Profile and Geologic Information The Site is mapped on the Preliminary geologic map showing Quaternary deposits of the Lodi quadrangle, California (Marchand and Atwater, 1979). It is depicted within a map unit of Holocene alluvium, described as "channel, levee, and floodplain deposits; chiefly silt and clay with fine sand along principal drainageways" (Plate 8). The surface and near surface soils located at the Site are reported by the Web Soil Survey (USDA, 2018) to be composed of Columbia fine sandy loam, drained (Plate 9). 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) Classification mmhos/cm Reaction ability absorption Symbol pH (in/hr) fields Columbia 0-12. Fine sandy loam, SM, <2 6.1 - 7.8 2.0 -6.0 Moderate: fine sandy SC-SM flooding, loam, 12-60: Stratified sand to silt <2 6.1 - 7.8 2.0 - 6.0 peres drained, 0- loam, SM slowly. • 2% slopes, 130 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 January 10, 2018, Live Oak excavated a shallow soil boring on each proposed parcel of the Site for the purpose of conducting percolation tests. The borings were four inches in diameter, 3.02 and 3.12 feet deep, and were excavated by hand auger (Table 2). The locations of the borings are indicated on Plate 10. The soil in the borings was much more clayey than that described by the Soil Survey. At location P1, silty, organic clay was encountered to a depth of 2.5 feet, followed by silty sand. At location P2, organic clayey silt was encountered to a depth of 1.5 feet, followed by silty, organic clay to a depth of 3.0 feet, followed by silty clay to the full depth of the hole and adjacent 10-foot ground-water boring. The soil logs are presented on Plates 11 and 12. Discussion of Soil Lithology Based on the soil observed in the borings, there appears to be moderate to good potential for percolation at the test locations. Sandy soils generally have a much • greater potential for percolation than fine-grained or cemented soils. However, a LOGE 1801 Page 5