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The wells were allowed to recover after purging A water sample was then collected with a fresh bailer Each sample was divided among three 40-m1 VOA vials The vials are supplied pre-cleaned to exact EPA protocols and contain the appropriate preservative The sample vials were labeled as to station, well, time, and sampler, and documented on the chain-of-custody sheet , they were then placed into zap lock bags and cooled to 40C with ice The samples were delivered to a California State Certified Laboratory using standard chain-of-custody procedures Field notes describing the collection of water samples are included in Appendix A Chemical Analysis Results The water samples were analyzed at American Environmental Network, AEN (DHS #1172) for Total Fuel Hydrocarbons (gasoline) with BTEX distinction, utilizing EPA Methods 5030 and 602 , respectively The analytical results from the water samples (MW1 , MW2 , and MW4 through 7) were all Below Reportable Limits (BRL) MW3 and MW8 indicated a level of TFH of 0 2 mg/L, and 7 4 mg/L respectively Benzene concentrations are 4 and 1300 Ag/L for MW3 and MW8 respectively The current localized impact of TFH-gasoline and benzene on ground water is depicted in Figures 5D and 6D The analytical results and pertinent reference data are listed in Table 1 . AEN' s laboratory report is included as Appendix B The ground water gauging obtained during the current monitoring round show a recharge to the aquifer since the last quarterly monitoring period The flow direction is to the south southwest from MW1 to MW3 , to south southeast from MW3 to MW7 with an average gradient of 0 002 feet per linear foot and indicates a somewhat stable hydraulic gradient TPH-G, BTEX concentrations have decreased to non-detection in MW4 and decreased slightly in MW8 since the last ground water monitoring on March 30 , 1995 , past analysis of ground water from MW4 have shown low to no detection of petroleum hydrocarbons MW3 indicates the first detection of any petroleum hydrocarbons in four years of ground water monitoring The vapor extraction (VE) test (report dated, April 17, 1995) ) as well as the ' spotty' occurrence of contamination in MW4 suggest that leading edge bio-activity may exist at this well and is contributing to degradation of petroleum hydrocarbons A comparison of the CO2 concentrations obtained from the VE test at MW4 and MW8 may substantiate the idea that bio-activity is abating the contamination at MW4 WE report 4/17/95-Table 1 & 2) MW8 had relatively elevated petroleum contamination in the vapor 4 USA 65 Sept ' 95 Qtr Rpt