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Delineation and Destruction Work Plan for Well B-1 Soil samples will be collected from each of the boring locations. The first soil sample in each borehole will be collected at the depth that the capillary fringe(i.e., saturated soil)is first observed and at 5-foot intervals below this depth until the final depth is reached. These are referred to as "5-foot-interval samples" in Section 2.4.3, Soil Samples. In the event that elevated PID readings, petroleum odor, or discoloration of soil is observed, the soil in the vicinity of these indications of potential contamination will be sampled. These are referred to as "observational samples" in Section 2.4.3. Additionally, one soil sample will be collected from beneath the bottom of the well during destruction of the well (see Section 3.2, Well Material Removal). The coordinates for each boring location will be recorded using a handheld GPS unit. 2.4.3 Soil Samples The 5-foot-interval and observational soil samples will be collected using a hollow stem auger drill rig. The borehole will be drilled to a depth of approximately 35 feet bgs, after which the rig will alternately drill several feet and sample soil in such a manner as to allow continuous core sampling between 35 feet bgs and the target depth. The soil coring tool will be lowered through the hollow stem of the auger and will be driven into the soil below the drill bit to sample undisturbed soil. This soil coring tool will be lined with acetate tubes/liners to allow for sample collection. The initial soil coring depth of 35 feet bgs was selected as a conservative estimate of the highest point reached by the capillary fringe over the past year. Upon retrieval of the acetate liner, to collect a 5-foot-interval sample, the appropriate length of core will be selected and cut. Teflon squares will be placed over the open ends of the acetate liner, and plastic endcaps will be placed over the Teflon. A Terra-Core device or similar method will be used to collect adjacent soil for preservation by EPA Method 5035. To collect an observational sample (or the sample from beneath the base of well B-1), soil will be scooped from the split core (or a down-hole soil sampling device) into an 8-ounce glass jar,using a clean (decontaminated) or dedicated trowel for each sample. A Terra-Core device or similar method will be used to collect adjacent soil for preservation by EPA Method 5035. Each sample will be labeled with a unique sample identifier and placed in a sealable plastic bag in a cooler on ice. The appropriate sample information will be entered onto a chain-of-custody form. Sampling personnel will wear new nitrile gloves during collection and handling of each sample. 10886-7 DUDEK 6 January 2019