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does not correlate well with the gradient data obtained during that sampling event . Perhaps a pattern will emerge when more data is available PLATE XVI shows the groundwater gradient as indicated from the June 8 data It is to the northeast at about 005 ' /foot . The direction correlates well with the regional gradient based on County Flood Control District maps As noted above, although MW-2 is directly downgradient from the removed UST' s, it did not record the highest levels on contamination MW-3 , which is also downgradient but farthest from the UST site, recorded the highest levels of BTEX & TPH-G PLATES XVII & XVIII show approximate lines of equal concentration of benzene & THP-G based on the June 8 sampling event . They show the highest levels to be southeast of the removed UST' s, while the groundwater gradient is to the northeast If the hydraulic gradient has been consistently in an easterly direction, the gasoline contamination may have moved in that direction away from the source, (the UST' s*)) It is also possible that there is may be another offsite source responsible for the anomaly There is • insufficient data available at this time to explain the discrepency Additional sampling events should assist in clarifying the issue . CONCLUSIONS Based upon the data obtained to date, the following conclusions appear to be valid. 1 . High levels of BTEX & TPH-G were detected in soil & ground- water samples taken from the three monitoring wells on the property. TPH as waste oil was encountered in MW-1 in soil samples from 16 ' bgl & 21 ' bgl, but not below that depth 2 . The depth at which soil contamination was first encountered, (with the exception of the core sample from 9 5 ' -10 ' in MW-2 , ) was 36 ' bgl in MW-1, 29 . 5 ' bgl in MW-2 , and 24 . 5 ' in MW-3 - (except for a minor amount of Xylene at 19 5 ' ) This data does not correlate well with the locations of the wells in reference to the removed UST' s, and the indicated hydraulic gradient MW-1 is the closest to the source, but encountered contamination below the other two wells Impacted soil was detected in MW-2 at 29 51 , although it is in a down- gradient position from the tank site . MW--3 , farthest from the source, encountered higher levels of BTEX & TPH-G at a shallower depth, (24 51 ) than MW-2 The concentrations of contamination and depths encountered is • contrary to what would be expected if the UST' s were the source 9