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• February,--1993 - Five (5) soil borings were placed as shown on PLATE IX to depths ranging from 37' to 52' bgl. Results of laboratory analysis of soil samples taken during that work are shown on SLE V, which revealed that BTEX & TPH-G were present in all borings at depths ranging from 11 ' to 52' bgl. EXHIBITS I thru V are the lithologic plots of those soil borings. Cross- sections through those soil borings are included as PLATE X. April 1993 - A workplan addendum was prepared by WJH to place four (4) monitoring wells in order to determine the extent of possible groundwater contamination. A copy of that addendum is included as AP EMIX„ C. May_. 1993 - Four, 4” OD monitoring wells were installed at the locations shown on PLATE V. Refer to the report prepared by WJH titled "PAR & Results of Groundwater Investigation" , dated August 5, 1993, for complete details of that work A portion of that report is included as APPENDILX D, EXHI ITS VI-IX are the litho- logic plots of those wells; completion details are shown on EXHIBITS X XIII . Laboratory analyzes of the soil samples from those wells, shown • on TABLE VI , revealed the scattered presence of minor amounts benzene, toluene, xylene, & TPH as gasoline in all 4 wells, and much higher levels from samples in the capillary fringe. BTEX & TPH-G were present in the water samples from all four wells; see TABLE VI1 for details. The hydraulic gradient was to the southwest. September. 1993 -- The first quarterly measurement & sampling of the wells showed the presence of BTEX & TPH-G in all four wells. The hydraulic gradient was shown to be to the southwest, almost identical in direction with the first sampling done in June. Refer to that report for more details. anuar 1 94 - The second quarterly measurement again showed the Presence of BTEX & TPH-G in all wells; the gradient continued to be to the southwest. See that report for details. April. 1994 -- The third quarterly report continued to show a gradient to the southwest. Significant levels of benzene & TPH as gasoline were present in all four wells; toluene, ethylbenzene & xYlene were also present in varying amounts. Monitoring well #3 is downgradient from the site of the removed UST, and has consistently recorded the highest levels of all tested sub- stances since sampling began. This is in agreement with the recorded data. However, MW--1, which is upgradzent, has measured the second highest levels. This suggests that either. (1) • another source exists offsite to the north or northeast; (2) the direction of the hydraulic gradient has varied since the UST 4