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1 samples were poured into 40 ml glass VOA vials, which were then preserved in an ice-filled cooler A field-prepared sampling equipment nnse blank and a laboratory-prepared trip blank ' were stored and transported in the cooler with the groundwater samples The samples were handled and transported under chain of custody The groundwater samples were delivered to Sequoia Analytical and analyzed for TPH-g by Cal EPA-modified EPA Method 8015, for BTEX by EPA Method 8020, and for MTBE by EPA ' Method 8020 For confirmation, the sample containing the highest concentration of MTBE was reanalyzed using EPA Method 8260 Table 2 lists the analytical results for this quarter (in boldface type) and for all previous quarterly samplings TPH-g was detected an the sample collected from MW7, at a concentration of 67 µg/L TPH-g and BTEX compounds were not detected in the samples collected from MW1, MW2, MW3, MW4, MWS, or MW6 MTBE was detected an the samples collected from wells MW3 and MW5, at concentrations of 4 7 µgfL ' (MW3) and 6 0µgA. (MW5) MTBE was detected at a concentration of 7 2/cglL in the sample from MW5 using EPA Method 8260 Analytical results are shown in Figure 1 Laboratory data sheets and chain-of-custody documentation are presented as Appendix B 3. REMEDIATION SYSTEM STATUS ' A soil vapor extraction system was installed at the site by a previous consultant (Fugro) and operated for approximately 5 months,from November 1995 to March 1996 Laboratory analytical results for samples of the extracted soil vapor (cumulative) collected by Fugro are listed in Table 3 A new soil vapor extraction (SVE) system has been installed by EA and was started upon inspection by the San Joaquin Valley Unified Aar Pollution Control District on 21 February 1997 Presently, soil vapor is extracted out of only two wells (VEW 1 and VEW2), because the screened intervals for the other three vapor extraction wells (MW2, MW3, and MW5) are submerged by the water table The system operated continuously during the entire quarter Influent concentrations and total pounds of hydrocarbons removed by the system are shown in Table 3 and Figure 2 Laboratory analytical results for samples of the extracted soil vapor collected by EA are shown in Table 4 4. WORK PROPOSED FOR NEXT QUARTER ' The seven groundwater monitoring wells and two vapor extraction wells will be monitored for the presence of LPH The seven groundwater monitoring wells will be sampled, and the samples will ' be analyzed for TPH-g,BTEX, and MTBE The SVE system operation will continue during the following quarter and performance will be monitored and reported in the next quarterly report WMI 70137 Q797 TX 2 2