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26 January 2007 AGE-NC Project No. 01-0839 ' Page 2 of 12 cone penetrometer testing. Lithologic data was collected from an initial CPT sounding utilizing a ' piezoeone (cone penetrometer with pore pressure measurement) tip; an adjacent twin boring was then advanced to collect soil and grab ground water samples from selected depths. ' 2.1. ADVANCEMENT OF CPT BORINGS ' The CPT investigation utilized a 25-ton,truck-mounted CPT drill rig equipped with 2-inch diameter hollow-stem rods.A hydraulic ram was utilized to advance a piezocone attached to the hollow-stem ' rod assembly to a total depth of 100 feet below surface grade(bsg)in sounding CPT-1 and 150 feet bsg in sounding CPT-2; a piezocone illustration is provided in Appendix C. Sounding CPT-1 was advanced approximately 20 feet east of monitoring well MW-1;sounding CPT-2 was advanced near ' the northeast corner of the current UST location(Figure 2). The soil parameters of piezocone tip resistance, sleeve friction, and pore water pressure were ' continuously measured as the piezocone was advanced to depth. Utilizing the soil parameters, a computerprogram interpreted general lithology types based on the CPTSoil Behavior Classification System (Robertson, P.K., Campanella, R.G, Gillespie, D., and Greig, J., 1986) and displayed the ' interpreted lithologies on a continuous CPT boring log. The CPT interpretive log is provided in Appendix C. ' 2.2. GRAB GROUND WATER AND SOIL SAMPLE COLLECTION AND ANALYSIS ' Grab ground water samples and a single soil sample were collected in a twin boring advanced adjacent to the initial CPT soundings. The samples were collected utilizing 1.75-inch diameter hollow-stem rods fitted with a HydroPunch ground water sampling assembly,which was pushed to specified sampling depths by the CPT drill rig; diagrams of the sampling assemblies are illustrated in Appendix C.Ground water and soil samples were collected from specified depth intervals(zones) ' based on CPT lithologic data acquired from the initial CPT sounding indicating favorable conditions for sampling. ' Ground water samples were collected using a HydroPunch sampling assembly pushed to specified zones, then withdrawn approximately 3 feet to expose an inlet screen; the interior of the sampling tool filled with water and a'/<-inch outer diameter stainless steel bailer was lowered and utilized to extract a ground water sample. Each ground water sample was transferred into three laboratory-supplied 40-milliliter(ml) volatile organic analysis (VOA) vials. A grab ground water sample was collected from the CPT-1 boring location between 88 feet and 85 feet bsg. Ground water samples were collected from the CPT-2 boring location at the following ' Advanced GeoEnvironmental,Inc.