SITE INFORMATION AND CORRESPONDENCE

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%,I %./ Al Olsen, R.E.H.S Laurie A. Cotulla, R.E.H.S June 10, 2003 Page 4 immediately adjacent to the parking lot.5 The Women's Center UST and the UST on the Property share common trenches because the Property and the Women's Center were at one time under common ownership. On May 22, 2002, San Joaquin County was on-site to supervise the collection of soil samples from the trenches excavated to expose the underground pipes and the removal of contaminated soil. These release investigation activities, performed under the supervision of the County, commenced corrective action at the Site. In conjunction with the investigation, a water sample was collected from an abandoned water well on the Property to determine if the well had been impacted by petroleum hydrocarbons.? Further investigation of the lateral and vertical extent of the release were outlined for the County's approval on June 3, 2002 and supplemented on June 5, 2002. The County approved the proposed investigation activities on June 7, 2002. On June 10, 2002 and June 11, 2002, the County was again on-site to supervise the collection of a grab water sample and soil samples in the vicinity of the UST and below the underground piping beneath the concrete basement floor of the 1916 building. These results were provided to the County in a report dated July 3, 2002'. The July 3, 2002 report noted that the soil sample collected from a boring adjacent to the UST at a depth of 15.5 bgs was contaminated by hydrocarbon constituents; but no deeper soil samples, including one collected a depth of 16 feet bgs, had detectable concentration of these contaminants. Condor concluded that soil contamination in the vicinity of the UST is restricted to depths shallower than 1.6 feet bgs. As the bottom of the UST is at 13 feet bgs, the contamination appeared to be constrained to a narrow depth range. .Because tight clays, which are characteristic of the typical soils in the vicinity of the Property, impede contaminant mobility, Condor concluded that the contamination resulted in a highly localized zone of impacted soil in the vicinity of the UST. The grab water sample frorn this same soil boring also had detectible concentrations of hydrocarbon constituents. However, Condor concluded that this sample represents cross-contamination of the sample during advancement of the boring because (i) Groundwater at the Site is greater than 30 feet bgs; (ii) the laboratory analytical results indicate that no soil samples collected at the Site from deeper than 15.5 feet bgs were impacted by hydrocarbon contamination; (iii) and tight clay soils restrict the movement of contaminants though the subsurface. 5 A water line pipe also was grouped with the other underground pipes. Soil samples were also collected in the parking lot adjacent to the UST on the Women's Center property ("Women's Ccnter UST") and the Women's Center authorized the Warwicks to test for contamination beneath the Women's Center UST. The results of these samples were summarized in the Underground Pipe Investigation and Removal Report dated June 24,2002. No detectible levels of hydrocarbons were present in the samples collected from the excavated trenches; however, the soil samples taken adjacent to the Women's Center UST contained petroleum hydrocarbon compounds and semi-volatile organic compounds above reporting levels. "We concede that the wrong terminology was used in labeling this report as a Phase 11 Site Assessment Report. DO WN E Y I B R A N D ATTORNEYS LLP