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i Soil Sampling ( Soil samples will be collected using a piston-type sampler.The sampling tool is pushed in the j 'closed'position to the desired sample interval. The inner cone tip portion of the sampler is then retracted approximately 12-inches,leaving a hollow soil sampler containing two inner 1.125-inch diameter by 6-inch long stainless steel soil sample tubes. The hollow sampler is advanced 12 inches,filling the sample tubes with soil.The sample tool is then retrieved.Soil samples will be prepared for the laboratory by covering each end of the tubes with a Teflon sheet and polyethylene cap. The samples will be labeled,placed in ziplock bags,and placed in XA j an ice-filled cooler. e Subsurface soil samples will be collected at each significantly different lithologic unit encountered vertically from the 5 borings installed around the former tank and pump area. Soil samples will, be analyzed for TPH-gas,benzene,toluene,ethylbenzene,xylenes (BTEX), oxygenates (MTBE, TAME,DIPE,ETBA,and TBA),hulk density,specific gravity and total organic carbon(TOC). To prevent cross-contamination from occurring between samples,a separate hole will be required for each soil sample collected below 50 ft bgs,the approximate depth to the top of the impacted groundwater. Groundwater Samples Grab groundwater samples will be collected from 7 boring locations using a HydropunchT' sampler or equivalent sampling equipment. Upon reaching the appropriate depth for sampling, the sampling device will be lowered to the bottom of the boring and advanced an additional 4 to 5 feet into the undisturbed portion of the aquifer. Groundwater samples will be extracted from the sampling device using a small diameter bailer and transferred to appropriate sample containers. Sample bottles to be analyzed for volatile organic compounds will be filled to overflowing so that no air bubbles are present within the bottle. All relevant information(e.g.,boring designation,volume of water extracted, time of sampling) will be recorded in a field notebook. Groundwater samples will be collected at each significantly different lithologic unit encountered vertically. The depth of the deepest sample will be dependent upon on how deep the CPT rig can push the sample rods.It is anticipated that CPT rig will be able to push to 130 ft bgs. The maximum depth of the groundwater samples collected from the two downgradient borings will be approximately 70 feet bgs. The shoulder of Highway 4 is approximately 30 feet below the elevation of the site, therefore,70 ft bgs corresponds to a site depth of approximately 100 ft } bgs. Monitoring data from piezometers NP-1-70',-80' and-90' indicate the maximum concentrations of petroleum hydrocarbons are detected at 80 ft bgs.Therefore, accounting for �( the slightly downward vertical gradient,70 ft bgs is an appropriate depth to intercept the downgradient plume, if it exists at this location. To prevent cross-contamination from occurring between samples,a separate hole will be required for each groundwater sample collected. All groundwater samples will be analyzed for TPH-gas and BTEX by EPA Method 8015/8020, and Methyl-tert-Butyl Ether (MTBE),tent-Amyl Methyl ether(TAME),Di-isopropyl ether i (DIPE),Ethyl-tert-butyl ether(ETRE),and tert-Butanol (TBA)by EPA Method 8260,in a state- certified laboratory. SFO/CABERNETIGRoUPs/EBGIoELMONTE/Puwr_33/WORKPuw_CPT.00c 5