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Kennedy Jenks Consultants 2.2.2.3 2008 Soil Characterization Kennedy/Jenks advanced eleven borings to characterize soils and shallow groundwater beneath the 150-acre field and vineyard immediately north of the facility in September 2008. Of these borings, three borings located in each of the two soil units identified by the SCS were selected to provide samples to further characterize soil conditions. In many of the soil borings, the upper 8 to 9 feet consisted of silty sand, and in borings KB-4 and KB-6 the entire 10 feet of the boring consisted of silty or well-graded sand. The clay and silt soils logged in the soil borings were very stiff to stiff and typically had low to no plasticity. Although some soils were very stiff to stiff, no cemented 'hardpans' were observed. The soil boring logs and analytical results were included in the ROWD (Kennedy/Jenks 2008). s 2.2.2.4 Soil Chemistry Analytical results from the soil samples are summarized in Table 1. In general, the Guard clay loam has higher organic matter and pH but, because of lower salinity, these soils have lower concentrations of most ions. The combination of moderate sodium absorption ratio (SAR) and {r low electrical conductivity (EC) in the subsoil are likely to limit soil permeability and is related to the hard pan that is common in the area. This soil appears to have adequate nutrient status in the surface two feet. 9 The Devries sandy loam has higher EC throughout the soil profile and very high soil nitrate, approximately 700 pounds of nitrate-nitrogen per acre. The active root zone appears to be deeper than that of the Guard soil. a 2.2.3 Regional Geology La The Central Valley regional aquifer system of California is a 400-mile long, northwest-trending asymmetric trough, averaging 50 miles in width. The significant water-producing geologic units in the Central Valley are the unconsolidated to semi-consolidated non-marine sediments (, ranging in age from approximately 25 million years to the present. The west side of the trough is bounded by pre-Tertiary and Tertiary marine sedimentary rocks of the Coast Ranges. The east , side of the Valley is underlain by pre-Tertiary igneous and metamorphic rocks of the Sierra Nevada foothills (San Joaquin River Group Authority 1999 [SJRGA 1999]). The southern two-thirds of the Central Valley is referred to as the San Joaquin Valley. The San Joaquin Valley basin contains up to six vertical miles of unconsolidated sediment, of which the top 2,000 feet contain freshwater. As lakes filled and drained over the last 24 million years, laterally extensive clay units were deposited, forming barriers to vertical groundwater movement (SJRGA 1999). The most extensive is the Corcoran Clay of the Tulare Formation, 1 encountered at depths between approximately 100 and 400 feet bgs mainly west of the San Joaquin River (DWR 1967). Where present, the Corcoran Clay serves as a confining layer 'dividing upper unconfined aquifers from lower confined aquifers (SJRGA 1999). 2.2.4 Regional Hydrogeology The facility is located in the northern portion of the Tracy Subbasin (subbasin 5-22.15) of the San Joaquin Valley Groundwater Basin (DWR 2006). Water-bearing formations include (from Page 4 Monitoring Well Installation Work Plan t Sutter Home Winery, Lodi, California L g Ys goupladnn4obWM865005.0i subftma108 ri or lmw install wrk phttext dw