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xi f 1 k • Third 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 overtime, 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 the ten shallow A-aquifer wells this quarter indicated the depth-to-groundwater ranged from approximately 23 57 to 24 83 feet below the top of the well casings The water level in monitoring well MW-4 was measured at 24 18 feet below the top of the well casing The water table in the A-aquifer has fallen approximately 5 feet during the last three months The groundwater table at the site is very slightly depressed in the center of the site, with a slight flow direction to the northeast on the south side of the site and toward the south on the north site of the site (Figure 3) Groundwater measurements taken in the three B-aquifer wells indicated the depth-to-groundwater ranged from approximately 31 55 to 32 73 feet below • the top of the well casings The water table in the B-aquifer has dropped approximately 10 feet during the last three months A groundwater gradient map for the B-aquifer was created and indicates a gradient of 0 001 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 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 59 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 site wells this quarter Minor concentrations of MTBE remain in the shallow groundwater of the A-aquifer in the vicinity of the of well RW-I 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 October 2004