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f Ace Tomato Work Plan (continued) The data;from these borings will be used to initially interpret contaminant extent and 4 evaluate the need and approach of site cleanup. One boring will be placed as close to 1 the underground tank fill box and dispenser as feasible (where the contaminant leakage was`observed) and up to four soil samples selected on the basis of;kfield evidence of contaminant presence, and one groundwater sample will be analyzed for presence of } contaminants. The three more distant -borings will collect a soil sample near the capillary fringe and one groundwater sample at surmised down gradient flow directions for chemical analysis from each of those three boreholes. t i Field Methods - Exploratory Borings Four exploratory borings will be drilled' at the locations shown on Figure 1. Drilling permits will be secured from SJC EHD, and a subsurface utility clearance will be performed prior to doing the fieldwork. The".boreholes will be drilled with GeoProbe truck mounted drilling equipment. All drilling equipment and sampling tools will be cleaned prior to arriving, and before leaving the site. The probe will be advanced collecting continuous` and interval soil. sampling,in each borehole. Soil samples retained for chemical analysis will be cut from. the liners at depths of suspected or obvious contaminant presence. Once retrieved and , dissembled, the soil filled acetate liner will be removed and the ends will be sealed with ' Teflon paper or foil and plastic end caps, labeled, logged onto chain`'of-custody forms and;placed on crushed ice in a chilled ice chest. i The boreholes will be logged using the .Unified Soil Classification System under the ! supervision of a registered geologist. Additional lithologic information will be collected i to describe the subsurface geology. Soil samples will be collected for analysis at five- i foot, intervals, at intervals of obvious contamination and possibly at stratigraphic + features ''of interest. Soil vapor measurements will be'taken with a�portable organic vapor Pkotoionization Detector (PID). Upon. completion of the borehole drilling and collection of soil samples, depth to groundwater measurements and water samples, the boreholes will be sealed per the permit requirements by backfilling With cement grout, placed from the bottom to top of each borehole with a tremie pipe. ,Drill soil cuttings, decontamination and grout water will be labeled and drummed and placed on-site at a client-designated storage location. Field Methods — Reconnaissance Groundwater Sampling Each exploratory boring will be sampled. The ground water samples collected from the boreholes will be used for a relatively rapid reconnaissance of the site groundwater Page 2 of 4 i {