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Scope of Work Exploratory Borings Up to six exploratory borings will be drilled at the site (Figure 4). The borings will be positioned to ascertain distribution of the contaminants in soil and groundwater under the site given the constraints of the site and relocated curbs and roadways. 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 borings will be used to define the uppermost water bearing strata, and at least one boring will be advanced to the contact of the underlying aquitard strata in the area of the soil excavation. Borehole depths are anticipated to be about 15-feet deep for this reconnaissance. The boreholes will be drilled with truck mounted hollowstem auger and/or direct push drilling equipment. All drilling equipment and sampling tools will be cleaned prior to arriving, and before leaving the site. The augers will be advanced to the desired sampling depth interval, and a drive split spoon sampler will be driven ahead of the drill bit. The sampler will then be retrieved and dissembled, and the soil filled brass liners, if retained for chemical analysis, will be sealed with Teflon® paper and plastic endcaps, labeled, logged onto chain-of-custody forms and place in a chilled ice chest. The boreholes will be logged using the Unified Soil Classification System under the supervision of a registered geologist using the attached Geoscience protocols Wright has developed for drilling, sealing, well construction and sampling. Additional lithologic information will be collected to describe the subsurface geology. Soil samples will be collected at minimum five-foot intervals, at intervals of obvious contamination and at stratigraphic features of interest. Upon completion of the borehole drilling and collection of information, the boreholes will be backfilled with grout, placed from the bottom to top of the borehole. Reconnaissance Groundwater Sampling Each borehole will be purged using calculated well volumes based upon the depth to water in each casing. Depth to groundwater measurements will be made to the nearest one-one hundredth of one foot from existing grade, and also checked for the presence of separate phase product. The groundwater sample will be carefully collected with a clean bailer and poured into the appropriate laboratory prepared container with minimum cavitation. Each water sample will be labeled, logged onto a chain-of-custody form, and placed in a chilled ice chest. Upon completion of well sampling, the borehole will be sealed using the PHS EHD permit requirements. This borehole stratigraphic and chemical analytical data will be reviewed to ascertain the need for and positioning of groundwater monitoring wells. Should groundwater monitoring wells be required, then the following well installation procedures would be used. Monitoring Well Installation Three monitoring wells will be installed using the six exploratory boreholes data to locate the wells for long term plume monitoring. The wells will be cased with Sch. 40 PVC casing, threaded together; glues will not be used. The slotted interval will be a 0.020 inch slot and the annular space around the slots will be backfilled with a 2/12 size sand. Previous experience has shown this to be a reliable well design in fine grained and stratified depositional environments. Final well design will be modified to the site specific conditions encountered in the borehole during drilling. Once Page 2