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Page 2 of-Custody form and transported to Superior Precision Analytical, a state- certified laboratory, for analysis. UST Complex and Product Piping Sampling Following UST removal, soil samples were collected between 2 to 3 feet beneath each end of the tanks (Figure 2). Samples TX-1-9.5' and TX-2-10'were collected at 9.5 feet below grade and 10 feet below grade respectively. Samples TX-3- 13% TX-4-13', TX-5-13', and TX-6-13' were collected at 13 feet below grade. Samples TX-7-16' and TX-8-16' were collected at 16 feet below grade. Upon the approval of Harlin Knoll from San Joaquin County Public Health Services, Environmental Health Division, samples TX-1-9.5', TX-2-10',TX-3-13',TX-4-13', TX-5-13', and TX-6-13' were not analyzed due to the over-excavation activities which extended beneath each of their depths Following over-excavation, additional samples were collected as described later in this report. Soil samples were also collected beneath the former fiberglass product piping. Samples P-1-3', P-2-3' and P-3-3' were collected at 3 feet below grade. An additional sample, P-4-3', was collected from beneath former steel product piping located to the north of the pump islands (Figure 2). Waste Oil Tank Remote Fill Piping Sampling • The remote fill piping (Figure 1) extending from the previously removed waste oil tank to the inside of the station budding was removed and a sample was obtained(Figure 2). Sample WO-1-2.5'was collected from approximately 2.5 feet below grade from inside the station building from beneath the former fill pipe. Excavation Sampling Additional excavation was performed on December 17, 1993 to facilitate the installation of anew UST complex,piping and pump islands. Approximately 1000 cubic yards of soil was removed and stockpiled (Figure 3). Following excavation, samples were collected from the sidewalls and bottom at vanous depths (Figure 3). Samples OX-1-16', OX-3-16', OX-6-16' and OX-8-16' were collected from the bottom of the excavation at 16 feet below grade. Samples OX-2-12',OX-5-12' and OX-7-12' were collected at 12 feet below grade. Sample OX-4-10' was collected at 10 feet below grade, and OX-9-15' was collected at 15 feet below grade from the excavation sidewalls. Eric W. Trevena and Harlin Knoll from San Joaquin County Public Health Services, Environmental Health Division were on site to direct and witness sampling. Groundwater was not encountered during excavation activities. Depth to groundwater is estimated to be approximately 70 feet below grade.