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4 t'f 0 1� Fourth Quarter 2004 Monitoring Report - - - Quik Stop Market No 121 Page 3 All three of the three deep wells, MW-6, MW-9 and MW-10, screened from 65 to 75 feet within the B-aquifer, were reported to be free of detectable TPHg/BTEX and fuel oxygenate compounds The results of the groundwater analysis are summarized in Table 2 A graph for well RW-1, summarizing MTBE concentrations over time, is also presented herein The analytical reports from STL, chain-of-custody documents and field notes are attached in Appendix B Discussion Groundwater measurements taken in three of the ten shallow A-aquifer wells this quarter indicated the depth-to-groundwater ranged from approximately 24 51 to 26 07 feet below the top of the well casings The water level in monitoring well MW-4 was measured at 25 45 feet below the top of the well casing The water table in the A-aquifer has fallen approximately 1 foot during the last three months Based on wells RW-1, MW-11 and MW-12, the groundwater table at the site shows a flow direction to the southeast (Figure 3) Groundwater measurements taken in the three B-aquifer wells indicated the depth-to-groundwater ranged from approximately 27 18 to 28 58 feet below the top of the well casings The water table in the B-aquifer has risen approximately 4 feet during the last three months This rise in the water table is due to decreased pumping of the B-aquifer A groundwater gradient map for the B-aquifer was created and indicates a gradient of 0 005 feet per foot to the northeast (Figure 4) Dissolved oxygen(D O ) readings were not collected this quarter due to the low water table at the site The D O readings for all of the wells are summarized in Table 3, and show D O readings from previous sample rounds Based on the groundwater data obtained during the quarter, it appears TPHg and BTEX compounds have been eliminated from all of the site wells Previous site data indicates MTBE is "non-detect" in a majority of the site wells The MTBE plume has been reduced to the immediate area around monitoring well RW-1 The MTBE concentration reported in well RW-1 has dropped from 160,000 ug/L on August 16, 2002 to a current concentration of 37 ug/L No MTBE was detected in the three B-aquifer wells this quarter A summary of the data collected during the operation of the System is presented in Table 3 To summarize the results, no TPHg and BTEX compounds were detected in any of the sampled wells this quarter Minor concentrations of MTBE remain to the shallow groundwater of the A- aquifer in the vicinity of well RW-1 The KVA C-Sparge system is continues to have a positive impact on the groundwater conditions at the site CCI will continue to work on and monitor the System during the next quarter The next quarterly sample round is scheduled for December IS 2004