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Vestar Development Company D47223.01 March 7, 2006 Page 2 the site is found within the Central Valley regional aquifer system, an unconfined aquifer system within the older alluvium and deeper deposits. The direction of regional groundwater flow and depth of first encountered groundwater underlying the site have not been assessed.However, according to a map published by the San Joaquin County Flood Control and Water Conservation District entitled Lines of Equal Elevation of water in wells, Spring 2003,the depth to first encountered groundwater underlying the site is estimated to be 20 feet below site grade, and the groundwater flow gradient in the vicinity of the site trends west. 2.3 Project History: Information obtained by Twining during the performance of a Phase I Environmental Site Assessment (Phase 1) indicated that the site has remained in mixed agricultural/residential use since at least 1937. The site has been primarily used for agricultural and rural residential since at least 1937. Two irrigation canals were noted along the eastern and western edges of the site, north of Henry Long Boulevard from 1937 to 1998. The irrigation canal observed near the eastern edge of the site is no longer noted in the 1998 aerial photograph. The 1983 aerial photograph revealed two structures located near the northern edge of Henry Long Boulevard, in the northern portion of the site. The structure surrounded by a chain-linked fence located in the central portion of the site,north of Henry Long Boulevard, is the location of an on-site natural gas well. In addition, a plastic aboveground storage tank(AST)was observed in the area of the on-site natural gas well the contents and purpose of this AST are unknown. According to the Phase I the adjacent properties have been primarily agricultural and rural residential land. However,the property located east of the site,south of Henry Long Boulevard,was previously used as a non-permitted asbestos dumpsite. 3.0 PURPOSE AND SCOPE The purpose of the proposed work scope is to assess the subsurface soil conditions beneath the site in the areas of concern noted in the Phase I (adjacent to the former asbestos dumpsite, adjacent to the on-site natural gas well, and in the area beneath the plastic AST). The following work is proposed to achieve the above referenced objective: • Obtain drilling permits from San Joaquin County Department of Environmental Health- (SJCDEH); • Mark the site for Underground Service Alert (USA) at least 48 hours prior to drilling; • Using a Direct Push Geoprobe® drill-rig, drill up to nineteen (19) soil borings at 50 foot intervals along the boundaries directly adjoining the former asbestos dumpsite. In addition, one soil boring will be drilled adjacent to the on-site natural gas well and another soil boring will be drilled adjacent to the plastic AST. The soil borings will be drilled to a total depth of 15 feet below site grade(bsg),with soil samples retained for analysis at five foot intervals, from surface to 15 feet bsg; • The surface, 5-foot, and 10-foot soil samples collected from the soil borings along the boundary with the former asbestos dumpsite will be analyzed for asbestos by polarized light microscopy with point count confirmation using California ARB Method(CARE 435). The 15 foot samples will be placed on hold pending results from the upper samples;