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. Quik Stop Market No 121 CCI Project No 12118-2 Page 3 Two of the three deep wells (B-aquifer), wells MW-9 and MW-10, screened from 65 to 75 feet within the B-aquifer, were reported to to be free of detectable TPHg, BTEX and MTBE Monitoring well MW-6 was reported to have 8 3 ug/L MTBE No other detectable compounds were reported in the three B-aquifer wells The results of the groundwater analysis are summarized in Table 2 The analytical reports from STL San Francisco and chain-of-custody documents are attached in Appendix B Discussion Based on the groundwater data obtained during the quarterly sample round, it appears the detected groundwater plume has contracted to the area near Quik Stop Market's fuel tanks, located on the southeast side of the site, near monitoring wells MW-3, MW-4 and RW-1 (Figures 2 and 3) Groundwater samples collected from perimeter wells MW-1, MW-2, MW-8, MW-7, MW-11 and MW-12 were reported to be free of detectable TPHg/BTEX and MTBE compounds Groundwater in the vicinity of monitoring wells MW-3, MW-5 and RW-1 were reported to have . the highest concentrations of MTBE at the subject site It appears MTBE remains in the upper shallow groundwater of the A-aquifer in the vicinity of the fuel tanks MTBE was detected in MW-4 (screened from 33 to 43 feet)at a concentration of 1 5 ug/L and continues to be detected in low concentrations in B-aquifer well MW-6, although at decreasing concentrations The other two B-aquifer wells, MW-9 and MW-10, were reported to be free of detectable petroleum compounds Groundwater measurements taken in ten of the shallow A-aquifer wells on April 9, 2002 indicated the depth-to-groundwater ranged from approximately 16 71 to 18 04 feet below the top of the well casings The water level in monitoring well MW-4 was measured at 17 08 feet below the top of the well casing The water table in the shallow A-aquifer remains at approximately the same level as reported in the January 2002 sample round Groundwater contours in the A- aquifer monitoring wells indicate there is a slight groundwater depression in the middle of the site with very slight gradients toward the site, from the southwest, north and east (Figure 4) A groundwater gradient map for the B-aquifer was created and indicates a gradient of 0 001 feet per foot to the northwest (Figure 5) CCI has prepared a Feasibility Study and Corrective Action Plan for the subject site to determine the most effective and cost efficient remediation program for the conditions which currently impact the site The Feasibility Study and Corrective Action Plan was submitted to the County, which has approved the installation of a KVA-C-Sparge System CCI is in the process of obtaining pre-approval of the cost of the remediation system from the Underground Storage Tank Cleanup Fund It is anticipated the system will be installed during the next quarter CCI will continue to monitor the site on a quarterly basis to gather additional groundwater quality data at