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The chemical MtBE was tested for this quarter. The only well in which it was found was BM-5. Earlier this well was reported with ' higher detection levels due to the amount of gasoline in the water. However, this month we tested for all of the oxygenates requested by the Regional Water Board and MtBE is one of the ' oxygenates. The reason MtBE was found in this well was the sabotage which occurred in 1993 , when an employee poured fresh gasoline into this well . Among the other oxygenates we noted TBA (Tertiary Butyl Alcohol) in wells MW-6, 7 , 8 , and 9 . The data does not suggest any of this came from the leak source, since wells BM-4, and 5 are in the source area. Wells BM 6 and 7 are on the margins of the source area, BM-8 is downgradient of the source area and BM--9 is well upgradient on adjacent property. ' The oxygen levels were measured using a YSI Model 51B oxygen level meter. The meter was calibrated the day before performing the testing. The oxygen level was measured 5 feet below the ' surface of the water table. The oxygen levels are about the same as last quarter due to the oxygen release agent in the water. During this quarterly event we removed the old spent socks in the ' wells and replaced them with fresh socks. The present material should remain active until April, 1998. The nitrates were checked this quarter due to testing irregularities in the past. This quarter nitrates were tested correctly by method 535 . 3 . The results are shown in Table 3A. Nitrogen is almost non-existent at this site which indicates that ' anaerobic activity is taking place in the source area. VAPOR EXTRACTION ' The Vapor Extraction System started on July 16, 1997 . Weekly reading are taken of the system. Table 5 lists the Days of Operation, Vapor Concentration, Vacuum, Flow Rate and the Pounds ' of gasoline recovered and the Total Pounds to date. To October 27, 1997 we have recovered about 18 ,584 pounds. This equates to about 2323 gallons of gasoline. Figure 5 shows in graphic form the decline of incoming vapor to the extractor. It started out in July at about 8000 TPHV (Total Petroleum Hydrocarbon Vapor) and has worked down to 5000 TPHV. Although the graph appears to have high and low areas the system has been operating normally through out this quarter. The irregular amount of vapor concentration is probably due to subsurface adjusting to the applied vacuum. Last quarter we stated a radius of influence ' for the system. This probably has increased as the soil becomes dryer due to the extraction system. CONCLUSIONS The next quarterly monitoring will take place in January, 1998. Page 2 t