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i ' a contents of the drums were transported b a licensed hauler for disposal at a approved 17H drums. The conte p y p licensed waste treatment site. The volume of groundwater removed from the wells and other measured 'r sampling parameters are noted on the water sampling logs included in Appendix B. 3.0 LABORATORY ANALYSIS The groundwater samples were transported to STL Chromalab Analytical Labs, Inc., a state-certified ' laboratory, located in Pleasanton, California. The groundwater samples were analyzed for the presence of TPH-G, BTEX, the five fuel oxygenates, and 1,2 DCA and EDB in accordance with USEPA Method 8260B. Copies of the laboratory analytical report and chain of custody record are in Appendix C. 4.0 SUMMARY OF RESULTS A summary of the analytical results from current and past well sampling is presented in Table 1. Based on the groundwater-level data for November 19, 2002, ATC has interpreted the groundwater gradient and flow direction for the upper aquifer as shown on Figure 3. In the upper aquifer monitoring wells MW-5, ' MW-6, MW-7 and MW-10, the groundwater elevation decreased from the previous quarter an average of 0.50 feet, ranging from 0.36 feet in monitoring well MW-9 to 0.78 feet in monitoring well MW-5. The ' apparent groundwater flow direction in the upper aquifer was generally southeasterly at a gradient of approximately 0.003 (Figure 3). Based on the groundwater-level data for November 09, 2002 (Table 1), ATC has interpreted the groundwater gradient and flow direction for the lower aquifer as shown on Figure 4. In the lower aquifer monitoring wells MW-IR, MW-2, MW-3, MW-4 and MW-8, the groundwater level decreased from the previous quarter an average of 0.5 feet, ranging from 0.36 feet in monitoring wells MW-9 to 0.58 in MW-3. The apparent groundwater flow direction in the lower aquifer was generally southeasterly at a gradient of approximately 0.002(Figure 4). ' Laboratory analysis of the water samples collected on November 09, 2002 indicates TPH-G, BTEX, and MTBE were not detected in groundwater samples collected from MW-8 in the local lower aquifer, or MW-10 in the local upper aquifer. BTEX compounds were not detected in the groundwater samples ' during this sampling event with the exception of MW-9 (concentrations of toluene at 1.1 micrograms per liter (4g/1) and total xylenes at 1.7 4g/1). TPH-G was only detected in MW-1R at 75 µg11. MTBE was detected in groundwater samples collected from MW-IR (31 µg/l), MW-2 (450 µg/l), MW-3 (0.53 µg/1), ' MW-4 (1.4 µg/l) and MW-9 (1.1 µg11) in the lower aquifer; and MW-5 (2,100 4g/1), MW-6 (3.4 µg/l) and MW-7 (1.4 4g11) in the upper aquifer. Fuel oxygenates other than MTBE (TBA, DIPE, ETBE, TAME), Axe?-rapt and 1,2-DCA and EDB were not detected in the groundwater samples collected from wells sampled this 4*U-Kk ak quarter with the exception of TBA in wells MW-2 (110 µg/1) and MW-5 (520 µg/l). The concentration6.3 !t- i•,. of MTBE in monitoring well MW-2 decreased significantly from 4,000 µg11 last quarter to 450 µg11 this IL quarter. The next quarterly groundwater sampling is scheduled for the first quarter of 2003. ¢` 3 . vtn i ' Quarterly GW Monitoring Report-4th Qtr 2002 NymATC QStop No. 132 Quik Stop Markets,Inc. ' j VROJEETS U K STOP MKTSQS Q22ReponsQoozuraoirrzo02Ftp ATC Project No. 75.62503.3203 February 11,2003 Page 2 of 3