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(� Department of Transportation (DOT) approved `17H drums and stored on site. The volume of groundwater removed from the wells and other measured sampling parameters are noted on the field sampling logs included in Appendix B. 3.0 LABORATORY ANALYSIS The groundwater samples were transported to Severn Trent Laboratories, Inc. (STL), a state-certified laboratory, located in Pleasanton, California. The groundwater samples were analyzed as follows: ■ Wells MW-1R, MW-2, MW-4, and MW-5 were analyzed for the presence of BTEX, TPHg, and the five fuel oxygenates (TAME, MTBE, DIPE, TBA, and ETRE)by EPA Method 8260B Copies of the laboratory analytical report and chain of custody record are provided in Appendix C. 4.0 SUMMARY OF RESULTS Based on groundwater elevation data for November the groundwater flow direction in wells in both the upper and lower screened intervals was towards the southeast at gradients of approximately 0.002 feet per foot(ft/ft)and 0.003 ft/ft, respectively (Figures 3 and 4). Because groundwater elevation is consistent wells screened in both the upper and lower zone, we infer the zones are hydraulically connected. The groundwater flow directions and gradients noted during this sampling event are consistent with historical trends. TPH-G concentration levels were less than 50 gg/L (the detection limit) in MW-1R, MW-2, and MW-5; in MW-4 the concentration level was 60 µg/L. ; BTEX compounds were sampled in MW-1R, MW-2, MW-4, and MW-5; only toluene was found above the detection limits in MW-4 (concentration of 1.1 4g/L). Oxygenates; The highest concentration of MtBE was reported in groundwater samples collected from upper zone well MW-5 at a concentration of 92 µg/L. MtBE was also reported in lower zone wells MW- 1R and MW-2 at concentrations of 1.6 Vg/L, 21 µg/L, respectively. MtBE was reported below detection levels in MW-4. TAME was present in MW-5 at concentrations of 0.74 µg/L. TBA was present in MW-5 at concentrations of 12 µg/L. t yj w nyu, The upper groundwater zone is represented by wells MW-5 and MW-10 only/Well MW-5 was analyzed for BTEX and all five fuel oxygenates. MW-10 was not sampled this quarter due to it being blocked by a vehicle. MW-5 is closest to the original source and has the highest historical concentrations at the site. Concentration of MtBE has shown a steady decrease in MW-5 since the peak in March of 2000."TBA in MW-5 has also shown a steady decrease and is now approaching the detection limit. TAME concentration in MW-5 has been less than 5 jug/L for the last five quarters. MtBE has been below detection levels in MW-10 for the last four quarters. �— The lower groundwater zone is represented by wells MW-1R, MW-2, MW-4, and MW-9. MW-9 was • not sampled this quarter due to it being blocked by a vehicle. Concentration of MtBE has decreased by Quarterly GW Monitoring Report--4th Qtr 2005 Quik Stop No. 132 Quik Stop Markets. Inc. ATC Project No.75.52503.3206 December 16,2005 Page 2 of 4