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After the depths to water were measured, all wells (MW 1-MW6, MW8--MW 10, MW 12, MW 13, RW1-RW4, P1, P2, IWI, and V3) were purged by a vacuum truck and sampled At least three well casing volumes of purge water were removed from each well before purging was terminated After purging, groundwater samples were collected with factory-cleaned disposable polyethylene bailers, which were tnple-rinsed with deionized water prior to sample collection Groundwater samples were collected in 40-m1 VOA vials The'vials were labeled and stored in an ice-filled cooler and transported under chain of custody Groundwater samples, a field-prepared rinse blank, and a laboratory-prepared trip blank were submitted to Sequoia Analytical, and analyzed for Total Petroleum Hydrocarbons as gasoline (TPH-g) by DHS-modified EPA Method 8015 and for benzene, toluene, ethylbenzene, and xylenes (BTEX) by EPA Method 8020 The analytical results for the samples collected on I I May are presented in boldface type in Table 1, along with results of previous analyses The laboratory analytical report and chain-of-custody documentation are included as Appendix B Detectable concentrations of petroleum hydrocarbons in the samples ranged from 130 µg/L (MW1) to 90,0001.4g/1- (RW3) for TPH-g, and from 14µg/L (MW5) to 7,600,ug/L (RW3) for benzene The concentration of TPH-g in the sample collected from MW8, located adjacent to the Shell service station and upgradient of the site, was 80,000 4g/L Groundwater sample analytical results are shown in Figure 1 The soil vapor extraction and air sparging system operated continuously through the quarter Influent and effluent concentrations from monthly self-monitoring are shown in Table 2 ' 3. WORK O PROPOSED FOR NEXT QUARTER Water table elevations in groundwater monitoring wells will be measured and groundwater samples collected in August 1995 The samples will be analyzed for TPH-g and BTEX The soil vapor extraction and air sparging system will continue to be operated and its progress monitored WP61 73942Q595 3 2