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I• VYATCo <br /> A S S O C I A T E S I N C . <br /> sample from each boring will be submitted for laboratory analysis. Soil sample selection will be <br /> based on PID measurements and field observations (i.e. odor and soil discoloration). <br /> One groundwater sample will be collected from each boring at the depth groundwater is first <br /> encountered, approximately 14 feet bgs. A Geoprobe® Screen Point 15 Groundwater Sampler <br /> will be threaded onto the leading end of the Geoprobe when the groundwater is encountered. <br /> While the sampler is advanced, O-ring seals and an expendable drive point will provide a <br /> watertight system to ensure sample integrity. <br /> When the tool has been advanced to the desired depth, extension rods will be sent downhole to <br /> brace the bottom of the sample screen as the tool casing is retracted. When the casing is <br /> retracted, up to 41-inches of screen with slot sizes of 0.004 inches will be exposed. Teflon tubing <br /> with a check valve attached to one end will be inserted down the casing until it is immersed in <br /> groundwater. Water will then be pumped through the tubing and to the ground surface by <br /> oscillating the tubing up and down. <br /> Following soil and groundwater sample collection, the borings will be backfilled with neat cement <br /> grout to the ground surface. All drill cuttings, if any, will be stored on site with existing <br /> stockpiled soil pending laboratory results. <br /> Soil and Groundwater Remediation <br /> Based on results of the previous investigation, the extent of the surface spill appears to be limited. <br /> In an effort to expedite remediation of the impacted soil and groundwater, ATC proposes to <br /> further excavate the vertical extent of impacted soil in the vicinity of the surface spill. An <br /> excavator will be used to remove the impacted soil. Excavated soil will be visually inspected and <br /> monitored with a PID for the presence of petroleum hydrocarbons. The excavated soil will be <br /> stockpiled on site pending characterization. <br /> Due to high the groundwater elevation, groundwater is expected to fill the excavation to a depth <br /> less than 14 feet bgs. One saturated volume of water will be extracted from the excavation using <br /> a vacuum truck. Depending on the rate of recharge, a second saturated volume may be extracted <br /> from the excavation. The groundwater will be transported off site for disposal at an appropriate <br /> facility. brj 4"4_t Qt <br /> Confirmation soil and groundwater samples will be collected for laboratory analysis. The <br /> excavation will then be backfilled to the ground surface using clean fill material. <br /> Sample Analysis <br /> Selected samples will be immediately placed on ice and delivered under chain-of-custody <br /> documentation to Sequoia Analytical, a State-certified laboratory, for analysis. Samples will be <br /> w:\822544orkplan.doc 3 <br />