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Tank Closure Report Quik Stop No. 121 Page 5 sample. The laboratory results are summarized in Table 1 and the laboratory reports are attached in Appendix C. Conclusions And Recommendations Based on data obtained during the tank excavations, visual observations, analytical laboratory results and the condition of the three fuel tanks at the time of their removal, it appears that petroleum hydrocarbon contamination has impacted the native sand at the capillary fringe of the water table. Groundwater encountered at approximately 15 feet below the ground surface has also been impacted. The suspected source of the soil and groundwater contamination maybe overspills or minor leaks from the product piping to the dispensers during the 14 year operation of the tanks. No apparent holes were observed in any of the three fiberglass tanks, with the exception of the patched hole on tank T-1 . All three fuel tanks appeared to be in reasonably good condition. No visibly contaminated pea-gravel was noted in the excavation after the fuel tanks were removed (site photographs are attached to Appendix D) . The six soil samples collected from the bottom of the excavation (approximately 14 to 15 feet) were reported to be relatively free of detectable TPHG/BTEX contamination. These six soil samples were, however, found to contain varying concentrations of MTBE, ranging from 43 ug/kg to 27, 000 ug/kg. The two grab water samples indicate that groundwater beneath the fuel tanks has been impacted with petroleum hydrocarbons . Over-excavating the remaining pea-gravel and capillary fringe area was not an option, since further excavation to remove the pea-gravel and some of the native sand would have seriously jeopardized the canopy and could have undermined the two streets nearby, Union Road and West Louis Avenue, as well as an historical marker which is located on the northwest corner of Union Road and West Louis Avenue. Based upon this data, Quik Stop prevented further collapse within the excavation and supported the canopy footing by back-filling the excavation with the stockpiled pea-gravel. Since the stockpiled material was virturaly free of petroleum contamination, it was Quik Stop' s and CCI ' s opinions that using the stockpiled pea-gravel would not add to any groundwater contamination that may exist at the site. Based upon field observations and laboratory analytical results, it is CCI ' s opinion that further environmental work is necessary to define the extent of soil and groundwater contamination in the area