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Mr Johnson <br /> Page 2 <br /> Groundwater monitoring wells MW1 and MW2 were installed in May 1991 by SSB <br /> Environmental Consultants These wells were also located near the underground tank <br /> cluster Well MW 1 was located dust west of the tanks and well MW2 was located just <br /> east of the tanks These wells were constructed of 2-inch diameter PVC and extended to <br /> depths of about 75 feet below grade Well MW8 was installed in April 1994 by Thrifty as <br /> part of the site assessment mentioned above Well MW8 was constructed of 2-tach <br /> diameter PVC and extended to about 58 feet below grade This well is located near the <br /> planned location of the new market building Figure 2 shows the locations of the <br /> monitoring wells and other pre-construction site features Table 1 presents construction <br /> specifics for each of the abandoned wells The drilling logs from these wells are attached <br /> as Appendix A <br /> TABLE I <br /> Well Construction Specifics (all dimensions in feet) <br /> WELL ID <br /> Parameter VWA VWB VWC MW1 MW2 MW8 <br /> Date of Installation 4122194 4122194 4122194 5123191 5124191 4122194 <br /> Diameter 2 in 2 in 2 in 2 in 2 in 2 in <br /> Total Depth 35 48 45 75 75 58 <br /> Screened Interval 35-5 48-8 45-10 75-45 75-45 58-38 <br /> Blank Casing 5-0 8-0 10-0 45-0 45-0 20-0 <br /> Filter Pack 35-4 48-7 45-8 75-43 7V <br /> 58-36 <br /> Depth to Top of Seal 3 4 6 40 34 <br /> Date of Abandonment 7111195 7111195 7111195 7111195 717111195 <br /> On July 11, 1995, JDR Environmental initiated abandonment of the wells The wells were <br /> accessed through the existing surface vaults, and were over-drilled using a hollow stem <br /> auger drilling ng Abandonment was accomplished by one of two procedural methods <br /> Some of the shallow wells were over-drilled with steel rods run through the well casing <br /> At the total well depth, the casing was retrieved, intact, through the auger stem In the <br /> deeper wells, an abandonment bit was used to pilot through the PVC casing, breaking it <br /> into small pieces as drilling advanced In this method the PVC cuttings mixed with the <br /> sand pack and soil cuttings and were retrieved at the surface via the auger flights In both <br /> cases the holes were over-drilled about five feet deeper than the total well depth to ensure <br /> complete removal of the well and fill materials The auger stem was then retrieved from <br /> the open holes at the completion of drilling All cuttings and waste well materials were <br /> left on site in 55-gallon DOT drums <br />