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Delineation and Destruction Work Plan for Well B-1 3.2 Well Material Removal The County EHD requires that all well material be removed when destroying a well. The well will be over-drilled using a hollow stem auger drill bit of 10 inches in diameter to a foot or two below the bottom of the well. All well material, which includes the 2-inch-diameter PVC well casing, sand filter pack,bentonite seal, and cement/bentonite annular seal,will be removed from the well. The well material will be stored in 55-gallon drums or placed in lined,roll-off storage bins,which will be hauled off site by a third-party disposal contractor. After the final depth has been reached, a soil sampling tool will be lowered through the hollow stem and driven into the soil at the base of the borehole to collect a sample from below the bottom of the well. This sample will be analyzed for VOCs and TPH (see Section 2.4.5, Laboratory Analyses). 3.3 Borehole Backfilling The 10-inch-diameter borehole will then be backfilled with a neat cement mixture. The neat cement mixture will consist of approximately 6 gallons of water per 94-pound bag of Portland cement. The neat cement mixture will be pumped into the borehole, starting from the bottom of the borehole using a 1-inch-diameter(or larger) tremie pipe. The borehole will be backfilled with neat cement to the ground surface. Any groundwater displaced during this grouting process will be contained in a 55-gallon drum and then transferred to the on-site treatment system for treatment. 4 FIELD EQUIPMENT Field equipment and supplies include the following: • Maps/plot plan • Safety equipment, as specified in the site-specific health and safety plan • Tape measure • Tools • Ballpoint pens • Camera and film • Sealable plastic bags (gallon and quart size) • Field notebook • Chain-of-custody forms (for soil, groundwater, and IDW samples) 10886-7 DUDEK 9 January 2019