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the boring with neat cement. This well was filled to grade with cement and finished flush to the existing asphalt surface. i ' 3.3 Excavation Prior to beginning the excavation, the site was prepared by removing trees, a storage shed, asphalt and concrete, and other materials in the vicinity of the anticipated excavation area. The contaminated soil stockpile area was prepared by removing vegetation and placing plastic sheeting on the ground surface. All aspects of the remedial excavations were witnessed or coordinated by AGS and San Joaquin County PHSIEHD personnel. A large diameter water line was identified that crossed the proposed area of excavation. The line provides service water to the cold storage facility from the above ground water storage tank. Because service could not be interrupted, a two phase excavation was developed to prevent damage to the water line. ' The firsthase of excavation p ca atzon began along the edge of the concrete reservoir located to the north ' of the former UST location (Figure 2). Structural limitations to the west, north and east prevented the removal of additional soils in these directions. The excavation was advanced to the south into the access road until field observations indicated that contaminant levels had ' decreased significantly. The second phase of excavation was performed to the west of the water line. Physical and '• structural limitations to the north and east prevented the removal of additional contaminated soils in those directions. The western boundary of the excavation was limited to within the area bounded by the fenceline. The volume of soil removed duringthe first phase of excavation included 917 cubic yards of P uncontaminated overburden and 1,147 cubic yards of gasoline impacted soil. The volume of soil removed during the second phase of excavation included 300 cubic yards of uncontaminated overburden and 375 cubic yards of gasoline impacted soil. The total volume of gasoline impacted soil removed during the remedial excavation was 1,522 cubic yards. This material was ' stockpiled in the open field area to the northwest of the excavation, on top of plastic sheeting. Soil samples were collected periodically from the interior, sidewalls and bottom of the excavation for headspace analysis. This was conducted in order to monitor the limits of soil excavation and to distinguish between contaminated soil and clean overburden. Soil samples ' collected for headspace readings were placed in a ziplock type storage bag and the fuel hydrocarbons were allowed to volatilize by warming the sample in the sun. When sufficient volatilization had occurred, the probe of a photoionization detector (PID) was inserted into the headspace of the bag and the resultant readings were recorded. PID headspace readings were also recorded during the collection of samples retained for laboratory analyses. • American Geological Services, Inc. CA95 DE-029 6