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UPDATE 27 4-22-94 to remain off since December 30, 1993 . The VES was operated for approximately fifteen minutes allowing enough time to purge the vapor recovery laterals of any ambient air and to allow formation gases to pass by the sample port . Once the sample was collected the VES was turned off. This sample was chain of custody delivered to MATRIX ENVIRONMENTAL LABORATORIES for analysis using EPA method 8020/5030, TPHg/BTEX. Laboratory results indicated the absence of gasoline range hydrocarbons and BTEX' s in the vapor stream, see Laboratory Report - Appendix B. The February 2, 1994 site visit was for the scheduled drilling of confirmation soil sample borings At this time three soil sample borings were drilled by Woodward Drilling and soil sampling and screening was performed by a WEGE geologist Screening of the three borings indicated that some level of petroleum hydrocarbons still existed in the areas of the borings and these boring were converted into two inch vapor extraction wells at that time, see Figure 3 , Table 4, and Appendix C - Workplan, Well Construction/Borehole Logs with Certified Laboratory Reports . Quarterly ground water sampling and restart of the VES occurred during a site visit on February 16, 1994 To show if the VES was giving false negatives to ground water sampling results, the VES was turned off on December 30, 1993 and was not restarted until after all water sa p es a een obtained on February 16 1994 Laboratory results indicate that the below c-ef-ecE'ion its for . gasoline range hydrocarbons, benzene, toluene and ethylbenzene and the low levels of xylenes that have been seen in the wells for over a year dad not change when the VES was shut down. The VES was then hooked to vapor extraction wells VSB13 , VSB14, VSB15 and MW5 and restarted prior to leaving the site . On February 21, 1994 , a site visit occurred to sample the VES, see Table 3 A flow rate of approximately 30 cubic feet per minute (cfm) was maintained through the carbon scrubs . Of this flow the majority was produced from MW5, ie 23 24 cfm The remaining 6 . 76 cfm was produced from the newly installed wells VSB13, VSB14 , and VSB15 . An influent sample obtained at this time indicated that approximately 1 . 65 pounds per day of hydrocarbons was being recovered During the March 4, 1994 site visit vacuum influence and depth to water was measured at the well heads On March 23 , 1994 , a site visit was conducted to obtain influent/effluent samples from the VES and to measure vacuum influence at the well heads. A flow rate of 35 cfm was producing approximately 1 . 7 lbs/day gasoline from a vapor stream consisting Of 0 52 mg/L gasoline range hydrocarbons and 0 . 021 mg/L xylene . Benzene, toluene and ethylbenzene were all below detection limits Of 0 5 ug/L. page2