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r I ■ l� manifests covering this event are included as EXHIBIT G. DIS____CUSSION OF RESULTS OF WORK PERFORMED TO Based upon an analysis of all work performed to date, the following observations appear valid: 1 . The limits of soil contamination have not yet been located due the inability to excavate additional material . Future definition of the soil plume will have to be accomplished by other methods. 2. The hydraulic gradient has been relatively stable - to the north & northeast. Monitoring well #2 is directly downgradient from the site of the removed UST, and has been the only well measuring BTEX & TPH-G. 3. The groundwater plume has been defined to the west & southeast of the site of the removed UST; it has not yet been defined to the north. 4. The source of the three purgable halocarbons detected in MW-1 & MW-2 is not known at this time. It is possible they may be from an offsite source, or entered the water table through the UST site, which was uncovered for many years. 5. The site which contained the UST has been filled with clean gravel & covered with concrete. There is no longer a surface conduit for possible contamination of the water table. 6. Additional work will be needed to define both the soil & groundwater plumes; existing structures, and very limited space will limit options available. RECOMMENDATIONS: Although we had previously recommended the placing of one (1 ) additional monitoring well in a downgradient position, we now believe that a number of shallow, small diameter hydraulic or hammer-driven soil/water probes would be the most effective method for delineating the limits of both soil & groundwater contamination. Evidence to date suggests the plume has migrated to the north or northeast, and most likely extends off the property. If that is the case, it would be best to determine the lateral extent of that plume prior to committing to additional wells. It is our understanding that our client has qualified for the 6