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Scope of Work 2.0 Ground Penetrating Radar and Utility Clearance Wright will perform a ground penetrating radar geophysical study to investigate and locate the excavation of former underground storage tanks, pipelines and existing septic system in order to implement this subsurface assessment. This work will also assist in locating other underground utilities that might be in the vicinity of the proposed exploratory borings. 3.0 Field Methods—Drilling and Sampling Exploratory Borings Exploratory borings will be drilled at the locations shown on Figure 1. Drilling permits will be secured from SJC/EHD, and the above referenced underground utility clearance will be performed prior to doing the fieldwork. Sample locations will be made at points l 0-feet either side of the former pipeline to collect soil samples from a depth of 3-feet below the ground surface. One boring will be advanced in the former tank pit and soil samples collected at 3, 6, and 9-feet below the ground surface. The boreholes will be drilled with truck mounted GeoProbe direct-push drilling equipment. All drilling equipment and sampling tools will be cleaned prior to arriving, between each sampling borehole and before leaving the site. The probe will collect continuous cores of soil in each borehole. The sampler will then be retrieved and dissembled and soil sample intervals retained for chemical analysis will be cut from the liners at depths noted above. The soil sample will be sealed with Teflon paper or foil and plastic endcaps, labeled, logged onto chain-of-custody forms and place in a chilled ice chest on crushed ice for transport to the laboratory. The boreholes will be continuously logged using the Unified Soil Classification System under the supervision of a professional geologist. Additional lithologic information will be collected as needed to describe the subsurface geology. Soil samples will be field screened with a portable photoionization detector (PID) for petroleum fuel hydrocarbon vapor and staining. Upon completion of the borehole drilling and collection of water samples, the boreholes will be backfilled with grout,placed from the bottom to top of the borehole per the permit requirements. 3.1 Field Methods—Contingency for Groundwater.Sampling from Open Boreholes If groundwater is encountered in the boreholes, the borehole will be sampled. A brief summary of these procedures follows: Each borehole will be advanced into the aquifer and temporarily cased for sampling. Depth to groundwater measurements will be made to the nearest one-one hundredth of one foot, and also checked for the presence of separate phase product. The water entering the borehole will be sampled using a clean disposable PVC bailer, and carefully 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 on crushed ice for transport to the laboratory. Page 2 of 3