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v , <br /> A S S O C I A T E S I N C <br /> significant clay layer is encountered that appears to separate the shallow aquifer from the deeper <br /> water bearing zones. ATC estimates that the CPT boring will be advanced to approximately 100 <br /> feet bgs. If no significant clay layer is encountered to a depth of 100 feet bgs, the CPT boring will <br /> be advanced further if subsurface conditions allow it. <br /> Once a significant clay layer has been discovered and the boring is advanced into another sand <br /> layer, a Geoprobe boring will be advanced adjacent to the CPT boring and a discrete groundwater <br /> sample should be collected from the deeper aquifer. After the sample has been collected, both <br /> borings will be grouted to the surface. <br /> This task also includes mobilization to the site, advancing six direct push soil borings, and <br /> collecting at least two soil sample and one groundwater sample from each boring. These borings <br /> will be advanced to evaluate the lateral extent of petroleum hydrocarbon impacted groundwater. <br /> It is anticipated that several of the borings will be advanced at off-site locations. Proposed boring <br /> locations are shown on Figure 2. <br /> Six soil borings will be advanced employing direct push technology (DPT) utilizing a truck <br /> mounted Geoprobe® soil probing unit to first encountered groundwater, anticipated to be <br /> approximately 25 feet below ground surface (bgs). Drilling will be conducted by State licensed <br /> Fisch Environmental (C57 #683865). A field geologist will be present to log soil samples. <br /> Descriptions of soil types encountered and sample collection intervals will be recorded on boring <br /> logs. Soil samples will be collected at five-foot intervals. Each soil sample will be field screened <br /> with a Photoionization Detection (PID) meter or similar instrument and at least two soil samples <br /> from each of the six borings, based on field observations (i.e. odor, discoloration, PID readings), <br /> will be placed in a cooler with ice and submitted for laboratory analysis. <br /> Based on recent measurements of the on-site monitoring wells, the depth to groundwater for this <br /> area is estimated to be approximately 25 feet bgs. When groundwater is encountered, one <br /> groundwater sample will be collected from each boring at the depth groundwater is first <br /> encountered. A Geoprobe® Screen Point 15 Groundwater Sampler will be threaded onto the <br /> leading end of the Geoprobe when the groundwater is encountered. While the sampler is <br /> advanced, O-ring seals and an expendable drive point will provide a watertight system to ensure <br /> 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 /> wA14981\reports\v43.doc 3 <br />