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. Monitoring Quik Stop Market No 121 CCI Protect No 12118-2 Page 3 Well MW-3, located on the southeast side of the property, was reported to contain detectable TPHg, at 45,000 micrograms per liter(ug/L), MTBE at a concentration of 96,000 ug/L and no detectable BTEX compounds above the detection limit Recovery well RW-1, located near the east side of the fuel tanks, was also reported to have detectable TPHg, at 52,000 ug/L, and no detectable BTEX compounds above the detection limit RW-1 was also reported to have 89,000 ug/L MTBE Monitoring well MW-4, screened from 33 to 43 feet in the A-aquifer, was reported to contain 68 ug/L MTBE, and no detectable TPHg or BTEX compounds Monitoring well MW- 5, located on the southwest side of the site, was reported to be free of detectable TPHg and BTEX compounds but contained 49 ug/L MTBE Monitoring wells MW-2 and MW-12 were reported to contain detectable MTBE, at 0 5 ug/L and 0 62 ug/L, respectively Monitoring wells MW-3, RW-1 and MW-12 were also sampled for acetone and formaldehyde The laboratory reported all three wells to be free of these two compounds All three deep wells (B-aquifer), 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 and BTEX compounds Monitoring well MW-10 was reported to be free of detectable TPHg/BTEX and fuel oxygenate . compounds Monitoring wells MW-6 and MW-9 were reported to have detectable MTBE, at 8 3 ug/L and 0 94 ug/L, respectively No other detectable compounds were reported in the three B- aquifer wells The results of the groundwater analysis are summarized in Table 2 Graphs for wells MW-3, MW-4 and RW-1, summarizing TPHG and MTBE concentrations over time, are presented The analytical reports from STL San Francisco and chain-of-custody documents are attached in Appendix B Remediation System Installation CCI installed the KVA ozone infection system beginning on July 22, 2002 A total of ten sparge wells were installed at the site CCI installed 8 sparge wells to depths of 28 feet, and two sparge wells to almost the bottom of the A-aquifer, at a depth of 38 feet Each sparge well was constructed with a 2-inch diameter, 18-inch long Spargepoint Each Sparge point was connected to the surface by a 3/4-inch diameter, schedule 80, PVC riser pipe Lonestar No 30 "sugar sand" was placed around each Spargepoint to approximately five feet above the top of the Spargepoint A two-foot thick bentonite clay spacer was placed on top of the sand and cement grout was pumped from above the bentonite to the surface, and a well head assembly was attached to the top of the riser pipe, and a 18-inch diameter surface vault box covers each Spargepoint The Spargepoints were then connected by digging a 4-inch wide by 12-mch deep trench Double contained tubing, consisting of 2-inch diameter, schedule 40 PVC pipe and 3/8-inch ozone-air supply tubing, was placed at the bottom of the trench leading to the master unit, located on the