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USGS topographic maps indicate several wells in the vicinity located between one and two miles west, north, and east of the RV Park; the nearest located over one mile east of the site. SOILS Five soil trenches were dug on June 2, 2005 to investigate the soil profile. A summary of soils found in the soil trenches is provided in Table 5. The location of the soil profiles is provided on Figure 2. The trenches were dug to a depth of at approximately 100 inches. The near surface soil consisted of a heavy clay loam to a depth of 21 to 46 inches. Underlying soil consisted of sandy loam, loam, sand and hardpan. In addition, four monitoring wells were constructed in Iate May and early June 2007. The location of the monitoring wells is provided in Figure 2. Near surface sediments were dominated by silts and sandy silts to approximately 35 to 40 feet below ground surface (bgs). Sand units, less than five feet thick, were observed interbedded with the silt in monitoring wells MW -2, MW -3, and MW -4. Wet sands and silty sands, including layers of sandy silt to silt less than five feet thick, were encountered between 40 to 50 feet bgs. The Soil Survey of San Joaquin County, California [ I ] reports that the rate of water intake of soils at the site ranges between 1.0-1.5 in/hr (15-22 gpd/ft2). GROUNDWATER In this section a description of current groundwater conditions at the proposed subsurface dispersal site is provided. Consideration is given to groundwater quality and depth. Four shallow monitoring wells are installed at the RV Park on May 31 and June 1, 2007. Groundwater beneath the site is located in a shallow, unconsolidated aquifer. Groundwater Depth Groundwater levels were measured in June 2007 and August 2007. Groundwater was encountered at depths ranging from 35.21 to 38.17 feet bgs, in June, and 41.40 to 46.71 feet bgs in August. A summary of groundwater elevations is provided in Table 6. Based on groundwater elevation measurements, groundwater flowed to the north to northwest in July 2007, and to the northwest in August 2007. Groundwater Quality Groundwater samples were collected from the monitoring wells in June 2007 and August 2007, and from the domestic well in June 2007. The results of the sampling events are presented in Table 7. Specific conductance (EC) concentrations ranged from 780 to 940 µmho/cm in samples collected from the monitoring wells in June 2007. EC was detected in the domestic well at a concentration French Camp — Report of Waste Discharge 5 SAB027102 July 2008 n:Lsab0271021documentslrwdlfrencheamprwdjuly rev final.doc