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14� S E C 0 R Confrimation Soil and Groundwater Sampling Work Plan 7-Eleven Store #21756 July 27, 2007 Page 3 PERMITTING AND UTILITY CLEARANCE SECOR will obtain the necessary soil boring permit from the SJCEHD. Prior to conducting subsurface work at the site, Underground Service Alert (USA) will be contacted to delineate subsurface piping near the site with surface markings. In addition, a private utility locator service will be contracted to clear the area surrounding the proposed monitoring well locations. DIRECT PUSH SOIL BORING INSTALLATION Soil Boring, Soil Sampling and Analysis SECOR will supervise the advancement GP-7 at the location shown on Figure 2. Boring GP-7 will be advanced using a truck-mounted rig equipped with a 2-inch diameter Macro Core®sampling device to a total depth of approximately 30 feet bgs. Soil samples collected at 15, 20, 25 and 30 feet bgs will be submitted for laboratory analysis. The soil samples will be analyzed TPHg, BTEX, MtBE, TBA, tert-amyl-methyl ether (TAME), ethyl-tert-butyl ether (EtBE), diisopropyl ether (DIPE), 1,2-Dichloroethane (1,2-DCA) and 1,2- Dibromoethane (EDB) by Environmental Protection Agency (EPA) Method 8260B. Soil samples will be collected using the 2-inch diameter inner liner from the sampling device that will be sealed with Teflon® sheeting and plastic caps, labeled and placed on ice in an insulated container for delivery to Kiff Analytical located in Davis, California. Down-hole sampling equipment will be cleaned between each sampling interval. Each soil sample will be screened for hydrocarbon vapors using a portable photoionization detector (PID). Soils encountered during drilling will be logged using the Unified Soil Classification System by a SECOR field geologist, working under the supervision of a California registered geologist. All soil generated through drilling will be placed in Department of Transportation (DOT) approved 55-gallon drums on site pending characterization and disposal. Water generated by steam cleaning will be contained in a steam-clean trailer and temporarily stored on site in DOT approved 55-gallon drums. Groundwater Sampling and analysis Based on recent depth to water measurements in the onsite groundwater monitoring wells, groundwater is expected to be encountered in GP-7 at approximately 17.5 feet bgs. A grab groundwater sample will be collected from GP-7 by placing a temporary poly vinyl chloride (PVC) 0.75-inch-diameter 0.02-inch-slot well screen within the direct push rods after collecting the soil sample at 20 feet bgs. The rods will then be raised to a point above the current depth to water and water will be allowed to enter the casing. Prior to collection of a water sample, the depth to water will be measured in the temporary casing. The water sample will be collected by lowering a clean disposable bailer or W'-diameter stainless steel bailer through the temporary casing to groundwater. The groundwater will be bailed from the casing, decanted from the bailer into 40-m1 VOA vials, and sealed with Teflon®-lined caps. Each VOA vial will be checked to ensure no air bubbles are present, 21756 Confirmation GP 7-27-07.doc SECORlntemational,Inc.