Laserfiche WebLink
( "kTC <br /> A S S O C I A T E S I N C . <br /> water bearing zones or to a maximum depth of 150 feet. For estimating purposes, ATC is <br /> assuming the CPT boring will be advanced to approximately 120 feet bgs. <br /> Three Geoprobe0 soil borings will be advanced to the first groundwater surface, approximately <br /> 80 to 85 feet below ground surface (bgs). Proposed boring locations are shown on Figure 2. The <br /> three borings will be advanced using truck mounted GeoprobeO narrow diameter, direct push <br /> technology. Drilling will be conducted by a State-licensed (C57) drilling company. A field <br /> geologist will be present to log all soil samples. Descriptions of soil types encountered and <br /> sample collection intervals will be recorded on boring logs. Soil samples will be collected at <br /> five-foot intervals, field screened with a Flame Ionization Detection (FID) meter, and an <br /> estimated four soil samples from each of the borings will be submitted for laboratory analysis. <br /> Soil sample selection will be based on FID measurements and field observations (i.e. odor and <br /> soil discoloration). <br /> One groundwater sample will be collected from each boring at the depth of approximately 80 to <br /> 85 feet bgs. A GeoprobeO 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 <br /> tubing with a check valve attached to one end will be inserted down the casing until it is <br /> immersed in groundwater. Water will then be pumped through the tubing and to the ground <br /> surface by oscillating the tubing up and down. <br /> Following soil and groundwater sample collection, the borings will be backfilled with neat <br /> cement grout to the ground surface. All drill cuttings, if any, will be stored on-site in a 5-gallon <br /> container pending laboratory results. <br /> Placement of BorinLys <br /> One CPT soil boring will be located between the former Tank #1 and Tank #3 locations to <br /> further evaluate the vertical extent of impacted groundwater and subsurface soil lithology. <br /> A total of three GeoprobeO soil borings will be located adjacent to the former UST locations to <br /> further determine the lateral extent of petroleum affected soil and groundwater. These borings <br /> will be located approximately 10 to 20 feet to the north, southeast, and southwest of the former <br /> UST pit location to further define the lateral extent of soil and groundwater contamination in <br /> these directions. Monitoring well MW-1, installed by ATC in 1999, defines the lateral extent of <br /> soil and groundwater contamination to the northwest of the former USTs. <br /> wA14885\repoM\wkpin.doc 4 <br />