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INTRODUCTION This report prepared by Touchstone Developments is intended to document soil sampling and over-excavation at the former Chevron service station #9-5490, located at the south-west corner of Airport Way and Harding Way in Stockton, California (Figure 1). Soil sampling was performed on September 3, 1993, following hoist removal. Over-excavation, additional sampling and stockpile sampling was performed on October 8, 1993. SITE ACTIVITIES Hoist removal and excavation of suspected contaminated soil was performed by Golden West Builders of Livermore,California. A Touchstone representative was on site to observe over-excavation activities and to collect soil samples from the excavation and stockpiled soil. Following the removal of three hydraulic hoists from the station building, Touchstone Developments collected soil samples beneath each of the former hoist locations at a depth of approximately 7 feet below grade, H-1-7, H-2-7, and H- 3-7 represent the samples collected. Total Oil &Grease at detectable levels was observed in sample H-2-7' (Table A). On October 8, 1993 approximately 3 cubic yards of soil was excavated from the area of formerly removed Hoist #2 and stockpiled on site. An additional sample was collected, H-2-8', at approximately 8 feet below grade (Analytical results are presented in Table A). All soil generated during hoist removal and over- excavation activities was stockpiled on site (Figure 1). One composite sample was collected, represented by HSP-IA-D, for disposal of at Forward Landfill, Manteca. SOIL SAMPLING Soil samples were collected from the back hoe bucket by removing the top few inches of soil and pushing a clean, six-inch-long (two inches in diameter) brass sample tube into the soil until completely full, or by using a "slide hammer sampler" supplied with a clean, six-inch-long (two inches in diameter) brass sample tube and driving it into the soil until completely full. The ends of the tubes were covered with teflon tape and sealed with plastic end caps. The samples were then labeled, placed in a cooler with blue ice, entered on a Chain- of Custody form and transported to Superior Precision Analytical, a State- certified laboratory. Soil samples collected from the excavation were analyzed for Total Oil & Grease according to Standard Method 5 5 20F. A copy of the analytical laboratory reports and Chain-of-Custody forms are presented in Appendix A.