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i Each .- well was purged before collecting water samples . Purging was completed only after water temperature, pH, and conductivity had stabilized. Purged water was contained in a labeled, secured 55 gallon drum on site. The wells were allowed to recover after purging. A water sample was then collected with a fresh bailer. Each sample was divided { among. two 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 an ice chest and cooled to 40C with ice . The samples were delivered to a California State Certified Laboratory and signed over to the lab 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, ;MW3 , MW5, MW6 and MW7) were all Below Reportable Limits (BRL) .. MW4 and MW8 indicated a level of TFH of 0 . 1 mg/L, and 12 mg/L ,..respectively. Benzene concentrations are 2 and 2100 pg/L for MW4 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 discharge to the aquifer since the last quarterly monitoring period. The flow direction is to the south southeast from MW1 to MW5, to south southwest from MW5 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 in MW4 and increased 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 . 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 'f contributing to degradation of petroleum hydrocarbons . 4 USA 65 June ' 95 Qtr Rpt G