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GEOMATRIX results are presented in Appendix A. Petroleum hydrocarbon-affected soil was found in two areas along the northeast edge of the site from the ground surface to a depth of approximately 31.5 feet bgs; the vertical and lateral extent of petroleum hydrocarbon-affected soil was not defined. Petroleum hydrocarbons were attributed to releases from the former OVP and TCE in shallow soil were attributed to releases from a drainpipe from the site building. Monitoring wells MW-1 and MW-2 were installed within petroleum hydrocarbon-affected soil and monitoring wells MW-3 and MW-4 were installed in a cross-gradient direction from the petroleum hydrocarbon-affected soil. Groundwater quality downgradient of the petroleum hydrocarbon-affected soil was not assessed during these investigations. 3.0 FIELD ACTIVITIES Geomatrix developed a work plan to further define the lateral and vertical extent of residual petroleum hydrocarbon and TCE in soil and groundwater quality downgradient of the affected soil. Depth to groundwater measurements were collected on June 1, 1999 to confirm the groundwater flow direction. Depth to groundwater ranged from 30.12 to 32.23 feet bgs, and the groundwater gradient was to the northeast,which is consistent with previously measured gradients (Figure 2). Approximately 0.02 feet (0.24 inches; slightly more than a sheen) of separate-phase petroleum hydrocarbons were measured in MW-1; this thickness is significantly less than that which had been previously reported. Seven soil boring were advanced on November 9 through 11, 1999 by Gregg Drilling and Testing Inc. (Gregg Drilling) under Geomatrix supervision using a hollow stem auger drill rig. Five of the borings (GMX-1, GMX-2, GMX-3, GMX-4 and GMX-5) were advanced on-site and two of the borings (GMX-6 and GMX-7) were advanced off-site (Figure 3). Prior to boring activities, Geomatrix notified Underground Service Alert and an underground utility survey was performed at each soil boring location by Cruz Brothers Sub-Surface Locators, Inc., of Milpitas, California. All drilling and soil sampling equipment was steam cleaned prior to use. The soil borings were advanced to depths ranging from.29.5 to 51.5 feet bgs. A continuous soil core was collected E from each boring and logged by a Geomatrix geologist according to Unified Soil Classification System (USCS) as presented in the American Society of Testing and Materials (ASTM) Standard D2488-90. Per RWQCB request; two soil samples were collected for chemical analysis from GMX-1 at depths of 10.5 and 21.0 feet bgs. One soil sample was collected for chemical analysis from soil borings GMX-2 through GMX-7 at depths ranging 1:1D0C_SAFL-1500M5380150IL GW RP'r.DOC 2