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i r Scope of Work Exploratory Borings and SoillSediment Sam lin Three exploratory borings will be drilled at the site (Figure 0. The borings will be positioned to ascertain distribution of the contaminants in soil and groundwater as. discussed above. Drilling and well installation permits will be secured from the PHS EHD, and all utilities will be cleared prior to doing_the field work. The existing safety plan will be used for this work. The boreholes will be drilled with GeoProbe drilling equipment. All drilling equipment and soil and groundwater sampling tools will be cleaned prior to arriving, between each borehole and before leavingthe site. The augers will be advanced to the desired sampling depth interval, and an acetate liner-core sampler will be driven ahead of the drill bit. The sampler will then be retrieved and dissembled, and the soil filled acetate liners retained for --J.chemical analysis _ ail?:be-sealed Lvith Teflon®=paper,or.fail and,plastic.-endcans,„labeled, logged onto chain-of-custody forms and place in a chilled ice chest on crushed ice. The boreholes will be logged using the Unified Soil Classification System under the supervision of a registered geologist (the attached Geoscience protocols Wright has developed for drilling, sealing, well construction and sampling are provided as the general } use protocols). The samples will be collected at minimum five-foot intervals, at intervals of obvious contamination and at stratigraphic features of interest. Soil samples will be field screened for contaminant presence using staining and vapor (soil outgassing in plastic bags measured with a field photoionization meter; please note that field vapor readings are reconnaissance only). Additional lithologic information will be collected to describe the subsurface geology as needed. . Upon completion of the borehole drilling and collection of information, the boreholes will be backfilled with cement grout, placed from the bottom to top of the'borehole. Groundwater Sam lin - Boreholes A groundwater sample will be collected from each borehole. These;ground water samples will be used to ascertain groundwater contamination near the edges of the excavation. A brief summary of these borehole sampling procedure follows: Each borehole will be advanced into the aquifer with the probe sampler. A Geoprobe-designed discrete screen sampler will then be placed into the borehole and advanced to the interval of interest (estimated to be 15- to 17 feet within the aquifer). The probe sleeve will then be retracted -- ---- - to expose the`Axeeri aitd opening-the groundwater-sairipling poft. The depth to groundwater from the surface grade will be measured and the borehole checked for presence of separate phase product. Each water sample will be carefully collected with a clean bailer and poured into the appropriate laboratory prepared container with minimum cavitation. The water sample will be labeled, logged onto a chain-of- custody form, and placed in a chilled ice chest. Upon completion of all borehole sampling, the boreholes will be sealed as discussed above. Chemical Analysis Up to (9) soil/sediment (aquitard) and three (3) groundwater samples will be analyzed at a State certified analytical laboratory from the exploratory borings. These samples will be tested for the following; Total Petroleum Hydrocarbons as Gasoline (TPHG), Benzene (B),' Toluene (T), Ethylbenzene (E) and Xylene (X), and Methyl-tert-butyl-ether and fuel oxygenates using EPA Methods 351018015, 8020 and 8260. .The analyses will be run on an "normal" turnaround (five working days). Page 2,