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Please refer to site map for tank locations. On June 15, 1995 a 12,000 gallon gasoline UST located to the west of the pump islands was removed from the ground. Three soil samples were collected from the native soil beneath the tank with the following results. SOIL SAMPLE RESULTS TANK#3 (ppm) SAMPLE TPH BENZENE TOLUENE ETHYL XYLENE LEAD ID GASOLINE BENZENE TK3-SOUTH 3900 <10 120 6.5 540 <5.0 13' TK3-CENTER <1.0 <0.005 0.0056 <0.005 0.0062 <5.0 14' T"-NORTH 8.3 <0.005 0.010 0.007 0.130 <5.0 13' The two soil samples collected from beneath the piping (after some limited over-excavation) showed nondetectable levels of the above noted constituents. On June 28, 1995,the south end of the former UST tank pit was trenched to a total depth of 27'below ground surface. The soil was screened during the trenching using a flame ionizing detector (FID) which indicated increasing concentrations with deeper depths. The hole was then backfilled using compacted clean soil to grade. The area around this tank will need assessment to determine full extent of impact and feasibility studies to determine most cost effective approach to cleanup. The dispenser island,piping runs and other tank sites noted above(except tank#5)will need assessment and if necessary, remedial feasibility evaluation to determine the most cost effective approach to clean up. Monitoring wells need to be installed as necessary based on field measurements to determine full extent of groundwater Impact. All work noted above shall be completed, as best as possible, during one mobilization attempt WORK TO BE PERFORMED TASK 1 PLANNING AND PERMITS A. Prepare a project workplan. B. Prepare a site health and safety plan. C. Submit the workplan, the health and safety plan, a schedule of implementation, a completed permit to bore application and the associated$89.00 fee to San Joaquin County Public Health Services,Environmental Health Division (PHS/EHD)for review. TASK 2 SOIL BORING, MONITORING WELL,VAPOR EXTRACTION WELL INSTALLATION AND SAMPLING A. Drill and sample sufficient soil borings to determine the full extent of the soil contamination in and around the areas mentioned above. At least three of these soil borings must be drilled and logged continuously. The need for additional soil borings shall be determined in the field, as much as possible, using either a flame ionizing detector or a photoionizing detector (calibrated) and in consultation with PHS/EHD. B. Drill,sample and complete as monitoring wells sufficient soil borings to determine the full extent of groundwater contamination at the site. The need for additional monitoring wells shall be determined, as best as possible, using field meters as described above,on soil in the capillary fringe or the saturated zone and in consultation with PHS/EHD. C. Drill, sample and complete as soil vapor extraction test wells at least three soil borings in the area of known impact(tank#3). The construction of the vapor extraction test wells should be dependant on the soil lithology 2