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Soil excavated from the tank pit was stockpiled on-site and soil samples were collected from beneath the tanks (two samples each at 15 feet) and dispensers (one sample each at 3 feet). The data indicate that leakage has occurred from Tani:92 and Dispenser#2 into soil. A water sample collected from the tank pit was also contaminated.. Six exploratory borings were drilled in and around the former underground storage tack pit in February 2003. The borings revealed T'PHG, TPHD, MTBE and Bunker Oil in borings adjacent to the former tank pit and north of the building. Separate phase product was observed in Borings B-3, B-4 and B-5. Residual_contaminants with low BTEX were interpreted present in the tank pit. vicinity. MTBE and low levels of TAME and TBA were present at B-1,B--2 and B-3 (see Figure 1). Since data was collected from uncased boreholes in which groundwater had not stabilized, a plot of groundwater was not prepared. The contaminant distribution indicated tank leakage has reached groundwater and moved in. a roughly northerly direction. The northerly and easterly extent of the dissolved plume was not mapped during this assessment(see Figure 1). Information regarding former oil transmission pipelines crossing the property came to light just prior to starting this study. Wright contacted Chevron Oil regarding these pipelines and their consultant, SAIC, came onto the property to collect duplicate soil and groundwater samples while Wright was conducting the Geoprobe portion of the investigation. Two old pipelines cross the property near the formes [1ST pit and where previous borings had been advanced. Wright will briefly discuss the pipeline and possible influence on the site and it is our understanding that the City will schedule a meeting with SAIC regarding the results of this study. By agreement, Wright and Chevron shared sample analysis results with the consent of the City. Wright initially performed a GeoProbe soil and groundwater sampling study to collect site data and use it to locate the monitoring wells. Once the data was reviewed by EHD, Wright and SJC/EHD then selected locations where four(4) monitoring wells were installed. 2.0 2000-foot Radius Well Survey and Sensitive Receptor Survey Wright has previously perforated a 2000-foot well survey and submitted that information to the EHD in 2003. 3.0 Field Methods—Drilling and Sampling GeoProbe Exploratory Borings Exploratory borings were drilled at the locations shown on Figure 1. Drilling permits were secured from SJC,`EHD, and the above referenced underground utility clearance was performed prior to doing the fieldwork. The sail borings were advanced to depths of about 25 to 35 feet to further define the dissolved plume northerly and easterly extent, The boreholes were drilled with truck mounted GeoProbe direct-push drilling equipment. All drilling equipment and sampling tools were cleaned prior to arriving, between each sampling borehole and before leaving the site. Page 2 of 14