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r or capillary-fringe contamination is detected in the wells, one or two borings will be drilled within the tank cavity to determine the maximum depth of soil contamination. If hydrocarbon vapors are detected in soil samples from the capillary fringe, it can be assumed that the entire vadose zone is contaminated within the tank pit and no additional borings will be required. The proposed assessment procedures are itemized below: 1) Notify the PHS/EHD 48 hours prior to field work. 2) Drill three soil borings using truck-mounted, continuous- flight, 8-inch diameter hollow-stem augers. 3) obtain discrete soil samples at five-foot intervals, using a split-spoon sampler loaded with three brass sample tubes. 4) Decontaminate sampling equipment in a tri-sodium phosphate solution (TSP) and rinse twice with water prior to each sampling run. 5) Preserve soil samples in the lower brass tube by covering both ends with aluminum foil, capping, and sealing with tape. 6) Label and log soil samples on a chain-of-custody form. 7) Store samples under ice pending delivery to a state-certified laboratory. 8) Monitor auger returns and soil sample duplicates for the presence of volatile organics using a photo-ionization detector (PID) . 9) Log auger returns and soil samples in the middle and upper brass tubes .in accordance with the Unified Soil Classification System. lo) Contain soil cuttings on plastic sheeting and store on-site pending analytical results. 11) Steam clean augers between borings to prevent cross contamination. 12) Complete the borings as groundwater monitoring wells in accordance with the well design shown in Figure 3 . 13) Develop the wells using a drill-mounted surge block, and add additional sand before grouting, if necessary. 14) No sooner than 48 hours after completion, measure depth to standing water in all wells and survey casing elevations. 2