Laserfiche WebLink
After the depths to water were measured, all wells (MW 1, MW4, MW 8—MW 10, MW 12, MW 13, <br /> RW1—RW4, P1, IW1, and V3) were purged by a vacuum truck and sampled At least one well <br /> casing volume and as much as three well casing volumes of purge water were removed from <br /> each well before purging was terminated After purging, groundwater samples were collected <br /> with disposable, factory-cleaned polyethylene bailers, which were tnple-nnsed with detonized <br />' water prior to sample collection Groundwater samples were collected in 40-m1 VOA vials The <br /> vials were labeled and stored in an ice-filled cooler and transported under chain of custody <br /> Groundwater samples, a field-prepared rinse blank, and a laboratory-prepared trip blank were <br /> submitted to Sequoia Analytical, and analyzed for Total Petroleum Hydrocarbons as gasoline <br /> (TPH-g) by DHS-modified EPA Method 8015 and for benzene, toluene, ethylbenzene, and <br />' xylenes (BTEX) by EPA Method 8020 <br /> The analytical results for the samples collected on 17 February are presented in boldface type in <br /> Table 1, along with results of previous analyses The laboratory analytical report and <br /> chain-of-custody documentation are included as Appendix B <br /> Detectable concentrations of petroleum hydrocarbons ranged from 480µg/L (MW1) to <br /> 85,000 µg/L (V3) for TPH-g, and from 6 4,ug/L (MW4) to 9,800 ug/L (RW3) for benzene The <br /> concentration of TPH-g in the sample collected from MW8, located adjacent to the Shell service <br />' station and upgradient of the site, was 72,000 µg/L Groundwater sample analytical results are <br /> shown in Figure 1 <br /> The soil vapor extraction system and air sparging systems operated through most of the quarter <br /> Influent and effluent concentrations from monthly self-monitoring are shown in Table 2 <br /> 3. WORK PROPOSED FOR NEXT QUARTER <br />' Water table elevations in groundwater monitoring wells will be measured and groundwater <br /> samples collected in May 1995 The samples will be analyzed for TPH-g and BTEX. The soil <br /> vapor extraction and air sparging system will continue to be operated and its progress monitored <br /> 1 <br />' WP61 73942Q295 2 2 <br />