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!XSia GEOMAT IX south of the site. On October 12 and 13,2000,borings GMX-30 through GMX-33 were advanced in the vicinity ofboring GMX-26,where petroleum-affected soil was encountered during the May 2000 investigation. In addition,boring GMX-29 was advanced on site within the area of known affected soil and a grab groundwater sample was collected to assess TPH concentrations in groundwater in this area;a previous grab groundwater sample from this area(GMX-6)was only analyzed for BTEX, MTBE and PAHs. Boring locations are shown on Figures 2 and 3. In both investigations,if petroleum hydrocarbon affected soil was encountered,a sample of the most visibly affected soil was collected for chemical analysis(excluding boring GMX-29,where soil samples from nearby borings had previously been analyzed). If no petroleum hydrocarbon affected soil was observed,a soil sample was collected from near the top of the water table and a grab groundwater sample was collected(excluding boring GMX-27 because it was located upgradient of affected soil). 4.0 FIELD AND ANALYTICAL METHODS Geomatrix contracted with Precision Sampling,Inc.(Precision)ofRichmond,California to advance the soil borings during the May and October 2000 investigations. Prior to conducting field activities, Geomatrix obtained a boring permit from the SJCPHS;Cruz Brothers Sub-Surface Locators,Inc.of Milpitas,Cahfamia,performed an underground utility clearance at each boring location;and Underground Service Alert(USA)was notified. Drilling and soil sampling equipment was steam cleaned prior to use. Soil borings were advanced by Precision using a hydraulically-driven,direct-push drive sampler equipped with a 2.5-inch-insidediameter steel drive casing containing a 1.6-inch-insidediameter core barrel. A continuous soil core was generated from each boring and logged according to Unified Soil Classification System(USCS)as presented in the American Society of Testing and Materials (ASTM)Standard D2488-90. Boring logs are presented in Appendix B. No petroleum hydrocarbon affected soil was observed in borings GMX-25,GMX-27,GMX-30, GMX-31 or GMX-33. One soil sample was collected from these borings at a depth above the water table. Petroleum hydrocarbon affected soil was encountered in boring GMX-26 between 6 and 8.5 feet bgs and in boring GMX-32 between 5.5 and 11.5 feet bgs;soil samples were collected from these borings where the most visibly affected soil was observed(at 8 and 9 feet bgs,respectively). Although petroleum hydrocarbon affected soil was observed at boring GMX-29(7 to 16.5 feet bgs), no soil samples were collected because this boring was advanced to collect a grab groundwater sample only. Soil samples were collected in clean stainless steel sleeves,sealed with Teflon sheets, '`SF3�EPMATA\DOC SAFE\6000S� 7.003WOMBOSOILGWR OV00 .DOC 4