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AZURE ENVIRONMENTAL ' Water table elevation'data collected at the Site indicate the general direction of ground-water flow is toward the northeast, with local variations of flow direction in the area adjacent to the former tank locations at the Site (Figure 3) These data are generally consistent with potentiometric data and interpretations of ground-water flow direction at the Site presented in previous investigation reports Shallow ground water in the site vicinity flows toward the northeast under a hydraulic ' gradient of approximately 0 002 ft/ft 3_2 Ground-Water Sampling and Laboratory Analysis ' On September 3, 1997, ground-water samples were collected from two downgradient monitoring wells at the Site (MW-9 and MW-10) The samples were analyzed for total petroleum ' hydrocarbons as gasoline(TPHg), benzene, toluene, ethylbenzene, and xylene (BTE3), and methyl tertiary-butyl ether(MTBE) compounds Historical laboratory analysis results are summarized in Table 3, laboratory certificates are included in Appendix A and field sampling data ' sheets are included in Appendix B Most recent ground-water monitoring data of benzene concentrations in ground water are illustrated in Figure 4 ' The downgradient extent of petroleum hydrocarbons in ground water is monitored at wells MW-9 and MW-10 Monitoring data collected for wells MW-9 and MW-10 in September 1997 indicate petroleum hydrocarbons, including benzene (<0 5 ppb) and MTBE (<50 ppb), were not detected These data are generally consistent with historical monitonng results, which indicate benzene has not been detected at MW-9 since January 1995 (0 6 ppb) and at MW-10 since October 1994 (0 6 ppb) These data continue to indicate the petroleum hydrocarbon plume has stabilized and is ' restricted to shallow ground water in the area adjacent to the former tank locations at the Site 4.0 TECBNICAL STATUS REPORT ' Work Completed Dunng the Third Quarter-1997 ' Work completed during the third quarter included performance of the quarterly ground-water monitoring program ' Work Expected to be Completed During the Fourth Quarter 1997 ' Work expected to be completed during the fourth quarter includes continued performance of the quarterly ground-water monitoring program ' On October 2, 1997, a water sample was collected at the well head of the fire system well at the Site The sample was sent to the laboratory for analysis of volatile organic and oxygenated compounds using EPA Method 8260 Sample analysis results will be reported in the fourth ' quarter 1997 report ' 2