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• <br /> ' 3a ADDITIONAL <br /> ' Blaes plans to use direct-push soil sampling methods at up to six soil bonng locations and install up to eight <br /> additional groundwater monitoring wells adjacent to the existing monitor wells The proposed locations of <br /> ' the soil borings and monitoring wells are shown on Figures 2 and 3 Data collected from these additional <br /> assessment activities will further define the extent of impacted soil below 70 feet bgs and provide data to <br /> assess current groundwater conditions beneath the site The following sections describe the specific tasks of <br /> the additional characterization program <br /> 31 SITE -HARL-TERIZATION- SOIL <br /> Although previous investigations conducted by Applied Consultants in 1993 indicated that hydrocarbons in <br /> ' soil extended to the groundwater surface (approximately 70 feet bgs), the PHS-EHD recently requested <br /> additional assessment to define the vertical extent of impacted soil to the depth of the historical low <br /> groundwater level dunng operation of the USTs at the site (90 feet bgs) Additional soil bonngs to at least <br /> 90 feet bgs will better evaluate the vertical and lateral extent of hydrocarbons in soil beneath the site The <br /> proposed locations of the soil borings are shown on Figure 3 <br /> ' 3 1 1 Direct-Pusb Soil Sampling <br /> ling <br /> Blaes proposes using a direct-push method drill rig to advance up to six soil borings to approximately 110 <br /> feet bgs or to the depth of laboratory non-detect for two consecutive 5-foot sample intervals One central <br /> boring (near former soil boring B7) will be drilled to determine the vertical extent of hydrocarbons in soil <br /> ' below the release area Up to three additional soil borings will be drilled in a triangular pattern around the <br /> release area to define the lateral extent of hydrocarbons in soil If necessary , two additional soil bonng <br /> may be drilled to further define the lateral extent of hydrocarbons in soil <br /> Discrete soil samples will be collected at 5 and/or 10-foot intervals within each boring, depending on <br /> ' Field results The previous soil sample data, extends to 70 and 75 feet bgs, so soil sampling in the central <br /> boring will begin at 70 or 75 feet bgs Blaes may choose to collect one or two soil samples in the zone of <br /> ' previous sampling to evaluate current hydrocarbon concentrations in known impacted intervals Up to <br /> six soil samples will be collected from each boring for laboratory analysis Soil sample collection and <br /> soil stratigraphic descriptions will be conducted at each sampling interval Samples for laboratory analysis <br /> will be properly contained, labeled, and stored pending delivery to a state-certified analytical laboratory <br /> Submittal of samples to the analytical laboratory will follow strict chain-of-custody protocol <br /> Blaes plans on contracting direct-push drilling and sampling s ry <br /> ices with Precision Sampling, Inc of <br /> ' 6 <br /> 1 <br />