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Geological Technics Inc. • • Page 5 Geoprobe Investigation Project No. 425.2 September 18,2008 2.1 Additional Site Characterization GTI proposes to advance up to Fifteen (15) geoprobes to 40 feet bgs. The locations of the proposed geoprobes are shown in Figure 2. The boreholes will be drilled using direct push technology operated by a licensed well driller. The anticipated depth to groundwater is approximately 12 feet below ground surface, based on existing monitoring wells. We propose to test groundwater at the depth intervals of the 17 to 22 and 32 to 37 that are called Zone A and Zone B in this report respectively. 2.1.1 Soil and Groundwater Sampling Procedure Up to Fifteen (15) direct push boreholes will be advanced in the proposed locations indicated in Figure 2. Soil samples will be collected continuously to 40 ft bgs depth. The boreholes will be drilled with a direct push rig owned and operated by a driller with a C57 license. The rig advances a direct push coring tool with a pneumatic hammer to a selected depth. Upon reaching that depth, a coring tool is opened and advanced further to fill the core barrel. The soil sample enters an acetate cylinder contained in the coring tool. Upon filling, the coring tool is pulled from the hole and the cylinder is removed. The cylinder is then cut and the selected interval is capped with plastic end caps and placed on ice for shipment to the laboratory. The remainder is used for geologic logging. A boring log providing sediment description using the USO and other field observations will be maintained by a geologist working under the supervision of a professional geologist. Up to three soil samples from each borehole will be submitted to the laboratory for analysis. GTI anticipates the analysis of the capillary fringe sample will be adequate however, field observations may warrant additional soil depths to be analyzed. Upon reaching the capillary fringe in each borehole, a hydropunch-type groundwater- sampling tool will be advanced into the groundwater and a groundwater sample will be collected from each borehole. The samples are collected using small diameter poly tubing with a Waterra type check-ball and gently transferred into VOA vials. The VOA vial is capped, inverted, tapped, and checked for headspace bubbles. The vial will be uniquely labeled and placed on ice for shipment to the laboratory. Clean non-latex nitrile gloves will be worn at all times in handling of the sample and sampling equipment. Since only selected soil samples collected will be submitted for laboratory analysis, a screening process will be used to gather additional information on the subsurface geology.