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PHYSICAL SETTING Topography The elevation of the Site, according to a United States Geological Survey topographic map, is approximately 45 feet above mean sea level (Plate 4). The Site is relatively flat. Geology The Site is mapped on the Preliminary geologic map of Cenozoic deposits of the Bellota quadrangle, California (Marchand, D.E., and Bartow, J.A., 1979). It is depicted within a map unit of Holocene alluvium, composed of channel and levee deposits (Plate 5). Soil Analysis Chemical and Physical Properties of the Soil 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 (Plate 6). The table below presents some selected properties of this soil type: 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 Columbia, fine Fine sandy loam; SM, Moderate: sandy loam, 0-12: SC-SM <2 6.1 - 7.8 2.0 -6.0 flooding, drained, Stratified sand to silt peres 0-2% slopes, 12-60: loam; SM <2 6.1 - 7.8 2.0 - 6.0 slowly. 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. The soil encountered on the Site was significantly more clayey than that described by the Soil Survey. On November 13, 2018, Live Oak excavated shallow soil borings on both proposed parcels of the Site for the purpose of conducting percolation tests. The borings were four 3.16 and 3.37 feet deep; silty clay was encountered to the full depth of each boring. Mass Transport Soil Properties The soil type will allow limited infiltration of water through the surface soils. LOGE 1916 Page 2