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G,701 caf£eeluncs Inc Page 4 SrteCha�actenzation Report Valentine(Castle Motors) Pioject No 723 2 Novembei 30 2001 Well o. Dia creep Slot and Packrans Urout Sea Seal ' - - sap - 2- sur ace-1_4 A 2-foot silt trap was placed on the bottom of the casing to aid in well development A ' surface seal was achieved by pumping a neat cement grout via a tremae tube (augmented with <4% bentonite) to the surface The well was secured with a locking watertight cap encased in flush mounted traffic-rated well box ' 30 RESULTS OF INVESTIGATION ' The analytical results and field observations are discussed below Tabular summaries of all soil analytical data are included in Appendix A, and the boring logs are included in Appendix B A site map with soil boring and monitoring well locations is included as Figure 2 3.1 Analytical Results Soil Sample Analysis • Low levels of BTEX were detected in all three of the soil samples submitted for analysis 0 Low levels of TPH-G were detected in two soil samples submitted for analysis • None of the oxygenated fuel compounds were detected in these samples ' O The 127-foot soil sample collected from SB-201 was obtained using the SiinulProbe' Tool This is the deepest soil sample obtained thus far in the investigation and it had an obvious petroleum hydrocarbon odor With the heaving/loose sands present at higher ' intervals, it cannot be definitively stated that the soil in the sampler was not slough in the bottom of the boring Table l in Appendix A is a full summary of all soil analytical data collected at the site 3.2 Geology and Field Observations ' The following section discusses the subjective field observations and geology documented during this investigation based on the interpretations of the field geologist • The site exhibits a primarily clayey geology The lithologic units explored in this investigation between 108 — 117 feet bgs were typically brown silts and clays The clays ranged from plastic and soft to hard depending on moisture content ' • It is suspected that sands are present in the 117 — 127 feet bgs interval This is supported by the sand-mud plug found on the sampler tip during sampling attempts in this interval The drilling mud was not viscous enough to preclude flushing the sand out ' of the sampler tube during the removal of over 100 feet of drill rod to retrieve the samplers 0 SJC PHS/EHD staff member Mr Jeffery Wong visited the site on Wednesday, October 24, 2001 When he assessed the slow progress of the drilling he directed GTI staff to 1