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' Drill Report Permit No. 07-390-SB January 8, 2008 1 A photoionization detector (PID) was used to screen soil samples from regular depth intervals for t the presence of volatile organic compounds (VOCs). Soil samples were transferred from the hand auger or core barrel into plastic bags, which were subsequently sealed. Once allowed to equilibrate, PID readings were taken from the head space of the bags and recorded on the boring log. These ' measurements were recorded on the boring logs included in Appendix A- A minimum of three soil samples were collected from each soil boring. Soil sample intervals ' selected for chemical analysis were typically collected by transferring soil from either the hand auger or acetate liners into laboratory-supplied glass jars. In some instances, the shallowest soil sample was collected from the sidewall of the soil boring just below the gravel base rock using a clean, ' decontaminated hand trowel. Soil sample intervals showing evidence of impact were preferentially selected for analytical testing. If no indication of impact was observed, soil samples were collected at pre-determined depth intervals as outlined in the Workplan Summaries. In the upper 10 feet of ' each boring, soil samples submitted for analytical testing were generally collected from approximately 0.5 (or just below base rock), 5 and 10 feet bgs. ' Following sample collection,the sample containers were labeled, logged on a chain-of-custody form, and immediately placed on ice in a cooler for transport to the laboratory. The location at which soil samples were collected at each soil boring is shown on the boring logs (Appendix A). At the end of ' the investigation, soil samples were transported by laboratory courier to Calscience Environmental Laboratory of Garden Grove, California for analyses. ' Upon completion of each borehole to the target depth, the borehole was backfilled with cement grout. For borings drilled in areas covered with gravel base rock, cement grout was backfilled to a few inches below the surface and surrounding gravel base rock was used to backfill the boring to the ' surface. Soil cuttings from the soil borings and decontamination water were placed in United Nations (LN- rated 55-gallon drums and staged on-site at a designated location approved by an on-site PG&E representative. A representative sample was collected from each drum for analytical testing to profile the waste for subsequent disposal off-site. ' Analytical Program All soil samples submitted to the laboratory for analysis were analyzed for one or more of the ' following: • Extractable total petroleum hydrocarbons (TPI quantified by carbon chain range using ' U.S. Environmental Protection Agency(EPA) Method 8015M; • Polychlorinated biphenyl (PCBs) using EPA Method 8082; and, • CAM 17 metals using EPA Methods 6010B and 7471A. 1 TERRA PACIFIC GROUP Page 2 1