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Confirmation Soil Sampling Work Plan Quik Stop Market No. 121 Page 2 Scope of Work The purpose of this investigation is to confirm (with updated samples)that the soil contamination in the vicinity of RW-1 and MW-4 has been remediated. CCI proposes to use a "Geoprobe" sampling rig to collect 2 soil samples from depths of approximately 6 and 14 feet at two selected areas near monitoring wells RW-1 and MW-4, located in the central portion of the site (Figure 2). The soil samples collected from the "Geoprobe" sample locations will be analyzed for total petroleum hydrocarbons as gasoline (TPHg), benzene, toluene, ethylbenzene and total xylenes (BTEX) and fuel oxygenates. In addition the soil samples will be tested for moisture content, porosity, and bulk density. Soil Sampling Using Geoprobe Sampling Rig Prior to commencing the field work, CCI will obtain the proper permits from the County to perform the proposed scope of work. CCI proposes to direct push two Geoprobe borings to depths of approximately 15 feet (capillary fringe). Soil samples will be collected at depths of 6 and 14 feet in each boring. The soil samples will be collected by using a 36-inch long, 2-inch diameter, closed piston sampling tube fitted with a 1.5 inch diameter stainless steel sampling tubes. Unlike split-spoon samplers, the piston sampler remains completely sealed while it is pushed or driven to the desired sampling depth. A piston stop-pin at the top of the sampler is removed by means of extension rods inserted in the probe rods after the sampler has been pushed or driven to the proposed sampling depth. This enables the piston to retract into the sample tube as it is pushed or driven to recover soil samples inside the sample chamber. Upon retrieval, the soil samples will be capped, labeled, logged on a chain-of-custody form and stored in a chilled ice chest containing water ice for preservation in the field and during transport to a state-certified laboratory. Upon completion of sampling at each location, bore holes will be sealed with Portland cement to the surface, allowed to settle, and topped-off with cold patch asphalt. Laboratory Analysis It is anticipated that up to up to four soil samples will be analyzed for petroleum compounds. The samples will be submitted to Entech Analytical Labs,Inc. (Entech),a state-certified laboratory located in Santa Clara, California, for chemical analysis. The laboratory reportedly employed methods approved by the RWQCB and the EPA. All samples will be analyzed for total petroleum hydrocarbons as gasoline (TPHg) using GC-MS and benzene, toluene, ethylbenzene and total xylenes (BTEX) and fuel oxygenates, using EPA Test Method 8260B. In addition, soil samples will be collected from the two boring locations and analyzed at a geotechnical soil laboratory for moisture content, porosity, and bulk density.