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i that the tanks had leaked. In January, 1990 , three monitoring wells (BM-1 , BM-2 and BM-3) were installed to a depth of 50 feet below ground surface (bgs) . At that time, the groundwater level was about 43 .5 feet bgs. When quarterly monitoring was performed in April, 1991 the wells ' were dry. They remained dry until April , 1995, after the heavy rains in the winter of 1995 . ' In April, 1992 , we installed 3 additional wells (BM-4 , BM-5 and BM-6) to replace the 3 original wells. in order to complete the definition of the groundwater and unsaturated zone contamination ' 5 additional wells were installed. Wells BM-7 and BM-8 were installed in August, 1993 and wells BM-9 , BM-10 and BM-11 were .installed in September, 1994 . Based upon groundwater information from well BM-9, 2 hydropunch samples were obtained in June, 1995 to help define the possible plume from the west. The findings from this work were reported in the Activity Report dated June 30 , 1995. PLUME DESCRIPTION ' Unsaturated zone The soil units under the site consist of clays, silts and sands . A cross section between BM-9 and boring B--1 is attached as Figure 4 . Based upon the sampling information from all the wells and borings we have estimated the position of the plume in the unsaturated zone for this site in Figures 2 , 3 and 4 . Two monitoring wells are located along the west side of the property, ' they are BM-3 and BM-7. BM-3 did not contain any recordable contamination and BM-7 had minor amounts of contamination in the zone from 40 to 50+ feet bgs. It is our belief the unsaturated contamination, from this site, extends a few feet to the west of BM-7. We do not believe site contamination has migrated more that 10 to 20 feet to the west of well BM-7 . No contamination ' has migrated to the west of well BM-3 . Saturated zone ' The hydraulic gradient of the groundwater under this site is to the northeast, which has been recorded in 10 quarterly monitoring reports out of 15 samplings. Three monitorings have recorded gradients to the east southeast, one monitoring has recorded a gradient to the north and one monitoring to the north northwest. The gradient average to the east is 0 .0072 feet/foot. The hydraulic conductivity at this site is 2 .94 feet/day The estimated effective porosity of the aquifer is 0 .30. The average fluid velocity in the water table aquifer is 0 .07 feet per day. Page 2 r