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CLOSURE REQUEST 5-31-94 detector (PID) . The trenches were advanced until no odor or detectable readings were found in an east-west direction. Once the contaminated soil was delineated in these trenched areas, excavating was performed in a north and south direction to the thirteen foot depth. Samples obtained from the base of the middle island area indicate that the excavation was successful in removing the contaminated soil from this area, see Table 1 (PL2 (EXC2A & 213) , and see Figure 7C. To enable the backhoe to proceed deeper, ramps were constructed into the west and east pump island areas . The excavations of the western and eastern pump islands were then deepened to the twenty foot depth. Samples obtained from the base of these two excavations show that contaminated soil still exists beneath the 20 foot depth, see Figure 7D and Table 4 (PL1 (EX1-PB) and PL4 (EX3-PA) ) . All samples were preserved, labeled, and chain of custody hand delivered to Chemtech Laboratories for analysis using EPA methods 8015 and 8020 with 5030 extraction. The excavated soil was covered with polyethylene liners, until laboratory results indicated the amount of soil that could be aerated at the site . Classification of the original UST removal excavated soil for this site showed that this soil can be handled as non hazardous waste, see Appendix E - "Hazardous Classification Report" in PRELIMINARY ASSESSMENT REPORT, dated December 15, 1989, Updated January 16, 1990 Vapor extraction wells were then placed into the UST excavation, the eastern pump island excavation and the western pump island excavation to the 40 foot depth A pilot study was then conducted on these wells from December 27, 1990 and ending on January 4, 1991, see pages 8 - 10 of UPDATE ASSESSMENT - STATUS REPORT #5, dated January 24 , 1991 This test indicated that vapor extraction could successfully remove the gasoline range hydrocarbons from the soil beneath this site. On March 31, 1992, under Authority to Construct Permit #AP 91-106, the Vapor Extraction System (VES) commenced to remove gasoline range hydrocarbons from wells P1, P3, EX, and MWS Prior to receiving the Authority to Construct Permit, the system operated from April 26 through November 21, 1991 under variances. As of March 23 , 1994 the VES has operated 745 days, removing an estimated 18, 224 pounds (2916 gallons) of gasoline range hydrocarbons from the soil, water and capillary fringe beneath this site. The above removal amount also includes the estimated hydrocarbons removed during the pilot study and under the variances . SAMPLE METHODS HAND AUGER/SAMPLER A WEGE geologist working directly under Ca Reg. Geologist #3037 and C-57 contracting license 513857, hand augered (411 diameter) holes six inches into the undisturbed native soil sidewalls and/or base of the excavations, see Figures 7A. . 7D. The auger was then removed and a hand sampler (2" X 611) with a clean brass sleeve was . hammered into the native soil, filling the sleeve with the native formation. page8