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Corp wells and the four (4) on the adjacent U S Chemical property A review of that report revealed that a mathematical error was made when converting water level measurements to mean sea level (msl , ) on Canteen Corp wells MW-5 & MW-7 . The interpretations shown in that report are incorrect ; maps showing the revised groundwater level gradient are included in this report as PLATES A & B They show a rather good correlation between the two sets of wells, indicating that there is probably hydraulic continuity across the area 3 . Laboratory results of all samplings done since the start of monitoring operations are tabulated on TABLE I In general, levels of all compounds have decreased since the last measurements in December This is most likely due to dilution from the 15 ' rise in the water table, although some natural bioremediation may be taking place . MW-3 , directly downgradient from the site of the removed UST, has consistently recorded the highest levels of BTEX & TPH-G MW-4 is the closest to, and on strike with, the tank site. Levels of contamination have generally decreased with time MW-2, which is slightly downgradient from the tank site, has also had a general decrease in levels since monitoring began 4 Levels in monitoring wells 5 & 6 have gone down signifi- cantly, which may be due to dilution Benzene & toluene increased slightly in MW-7 since the 1.2/94 sampling The reason for that change is not known at this time CONCLUSIONS : Based upon the data obtained to date, the following conclusions are offered- 1 The lateral extent of the groundwater plume appears to be have been fairly well defined to the west & southwest, based on results from MW-5 & MW-7 It has not yet been fully defined to the north & east of the property, and appears to extend beyond the site to the southeast, beneath U S Chemical PLATES C & D show lines of equal concentrations of benzene & TPH-G in the groundwater based upon the latest laboratory results They both continue to suggest that the plume extends beneath the U.S Chemical site 2 . The groundwater gradient as measured has been consistently in a southerly direction, which does not agree with the regional gradient, or with prior data from nearby monitoring wells located 2