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Groundwater samples were collected from the three wells using a disposable Teflon sampling bailer Groundwater was then placed in lab-supplied sample containers, sealed, labeled, and placed in a zip-lock plastic bag The packaged samples were placed in an iced cooler and transported under chain-of-custody manifest to NEI/GTEL Environmental Laboratories, Inc , a state of California-certified analytical laboratory located in Concord, California All three groundwater samples were analyzed for TPH-gasoline by Modified EPA Method 8015, benzene, ' toluene, ethlybenzene, and xylenes (BTEX) and methyl tertiary butyl ether (MTBE) by EPA Method 8020, and nitrate by EPA Method 353 1 In addition, the groundwater sample collected ' from MW-3 was analyzed for sulfate by EPA Method 375 4 All samples were analyzed on a standard turn-around ' Analytical results of the third quarter 1996 sampling event indicate that petroleum hydrocarbons were detected in groundwater samples collected from only one of the three monitoring wells Total Petroleum Hydrocarbons as gasoline were detected in the groundwater sample collected from MW-2 at 430 ug/L Benzene was also detected in this groundwater sample at 3 7 µg/L Groundwater sampled from MW-1 and MW-3 did not contain detectable concentrations of gasoline hydrocarbons Methyl tertiary butyl ether was not detected in any of the groundwater samples The current and historical analytical results and their detection limits are summarized in Table 3 and laboratory reports are included in Appendix B Waste water that was generated during this sampling event was placed in Department of Transportation approved 55-gallon drums The drums were fitted with a gasket and lid, and were then sealed with a bolted sealing ring The rings were tightened so that the contents of the drum ' would be secure from spillage Each drum was labeled with its contents, ongin and date generated The drums are currently being stored at the site pending disposition 5.0 Conclusions ' Work performed during the third quarter of 1996 included the monitoring and sampling of the three on-site monitoring wells Since the last monitoring event in May 1996, groundwater elevations have increased an average of 2 36 feet and groundwater flow and gradient characteristics have remained relatively constant Two of the three groundwater samples collected during the quarter did not contain detectable concentrations of gasoline hydrocarbons The groundwater sample collected from MW-2 did contain 430 yg/L of TPH-gasoline and 3