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GEOMATRIX Samples were collected at five-foot intervals from each boring using a Modified California drive sampler (2.5-inch diameter by 18-inches in length). Soil cores were logged by a Geo- matrix geologist according to the Unified Soil Classification System (USCS) as presented in the American Society of Testing and Materials (ASTM) Standard D2488-90. Recovered soil was screened for organic vapors using a Photoionization Detector (PID). Boring logs are ® included in Appendix B. ® A minimum of four soil samples were collected for laboratory analysis from each boring (GMX-8, GMX-9, and GMX-1B). Soil samples were collected at depths of approximately 5 and 10 feet bgs in each boring to evaluate the presence of petroleum constituents in shallow soil. Soil samples were also collected from each boring from approximately 30 feet bgs. This depth correlates to the vadose zone/groundwater interface and the depth at which petroleum impacted soil was identified during previous investigations. Additionally, a soil sample was collected from the terminus of each boring to confirm the vertical extent of affected soil, if pre- sent(i.e., the sample was collected from a depth where field observations/measurements do not indicate the presence of petroleum constituents). No affected soil was encountered in GMX-9 and, therefore, a terminus sample was collected near the bottom of the boring. Terminus sam- ples were collected from depths of 88.5, 59.5, and 90-feet bgs in borings GMX-8, GMX-9, and GMX-1B,respectively. An additional sample was collected at a depth of 55.0 feet from GMX-8 due to field indications (i.e., PID readings above background) that petroleum hydro- carbons may be present at this depth. Soil samples were collected in 6-inch stainless steel sleeves, sealed with Teflon sheets,plastic end caps, and silicon tape. Soil samples were labeled, sealed in plastic bags, and placed imme- diately in an ice-cooled chest for subsequent delivery to the analytical laboratory, Friedman and Bruya, Inc. (F&B), of Seattle, Washington (a State-of-California certified laboratory), under Geomatrix chain-of-custody procedures. Soil cuttings are stored on-site in labeled 55-gallon steel drums pending proper disposal. Following sampling, cement grout was placed in the boreholes from the bottom to the ground surface with a tremie pipe. Grouting was performed under the supervision of a SJC-PHS inspector. 4.2 MONITORING WELL SAMPLING As per the request of the RWQCB, field activities described herein were coordinated to coin- cide with groundwater monitoring activities at the WFS Vernalis facility. On May 20, 2002, \\oakI\deptdata\Doc_Safc16000s\6447.001\ReportlUS Can Soi1GW Rpt.doc 6