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clay loam, which had a gray to dark gray color. The locations of those samples is shown on PLATE V. After sampling was completed, the remaining stockpiled soil was returned to the excavation. The backhoe was repositioned at the east end of the west site and began removing soil from the west end of the east excavation. Mr. Ron Rowe, Sr. RENS, from the San Joaquin County EHD, arrived and witnessed the rest of the operation. Removed material consisted primarily of tan to buff clay with root casts & iron oxide staining. A very faint odor of "old" gasoline was noted in a few places . Soil samples were taken at 15 , & 16 ' below grade as described earlier; they were promptly sealed, labeled, and placed on ice. The locations of those samples are also shown on PLATE V. After completion of the sampling, the backhoe operator placed the remaining spoil pile material in the excavation. Mr. Hunter, the geologist in charge, delivered the samples to FGL Environmental laboratory under proper chain of custody. Analyses were to be BTEX (w/MBTE distinction, ) & TPHg using current Tri-Regional detection limits . RESULTS OF ABOVE WORK: TABLE II summarizes the results of the laboratory analyses of the soil samples taken on March 22, 1996; only soil sample W-1 at 15 ' bgl contained minor amounts of BTEX & TPHg; all others were below detection limits . MBTE was non-detect in all four samples. The laboratory sheets, QA/QC, & custody chain are attached as EXHIBIT G. The work done after removal of the tanks in 1989 showed that the sample from the west end of the east UST was the only one measuring any contamination. That area was clean during this work. The sample which did reveal low levels of contamination was near the east end of the west tank, W-1 (151 ) . The sample taken below it at 16 ' was clean. Although the sketch made during the 1989 sampling event appears to be properly oriented, it is possible that the samples were labeled incorrectly. In any event, residual levels found as a result of the most recent work are far below those allowed to be left in place using Table 2-1, the Leaching Potential Analysis worksheet for gasoline from the LUFT Manual . A copy of that sheet is included as PLATE VI . CONCLUSIONS : The levels of contamination measured during the March 22, 1996 work are below trigger levels based upon the LUFT manual, and do not pose a threat to groundwater. RECOMMENDATION: 4