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Final Technical Report, 2014 Monitoring Well Rehabilitation Program Bowie Mine 13 <br />Cleaning continued on September 4, 2014 using the jetting tool. Another 4,000 gallons was <br />injected between the depths of 1,562 feet to 1,688 feet. The downhole video taken after this <br />cleaning showed a piece of broken PVC bridging the 4 -inch to 2 -inch cross -over. After some <br />consultation, it was decided to try and push the broken piece down into the hole with the jet tool <br />on the tremie. The drillers were able to carefully push the piece of PVC down. At a depth of <br />1,682 feet the tremie could not be lowered any deeper. As the tremie pipe was tripped out of the <br />hole, the steel cross -over piece including a core barrel latch finger assembly emerged attached to <br />the tremie pipe. Subsequent video of the well showed the broken, jagged edge of 2 -inch PVC <br />casing where the steel cross -over had previously been. One more attempt to push the broken <br />piece of PVC down the well was made, but it got stuck again at a depth of 1,710 feet. At this <br />point, it was decided to try and cement off the bottom six perforated intervals of the 2 -inch <br />casing, filling the hole from the bottom at 1,914 feet to the top of the sixth perforated interval at <br />1,674 feet. A special removable plastic "nose cone" was fabricated for the tip of the 1 -inch <br />tremie pipe to allow it to pass into the broken 2 -inch PVC casing where the crossover once was. <br />Nine days, from September 7 to September 15, 2014 were spent injecting cement into the well in <br />stages to prevent any possible over filling. Each stage of cementing was allowed to setup <br />overnight and then the depth to the top of the cement plug was tagged prior to the following <br />cementing stage. It was originally calculated that less than two bags of cement should fill the 2- <br />inch casing to the target depth. But after pouring 15 bags of cement down the well, the top of <br />cement was tagged at a depth of 1,764 feet, nearly 100 feet short of the goal. During this <br />process, the drillers noticed a progressive increase in resistance as they pulled back rods after <br />each plug of cement was poured. On September 17, 2014 the tremie pipe could not be dropped <br />below a depth of 1,594 feet and the entire string was tripped out with difficulty. A video <br />inspection performed after removal of the tremie showed that the broken edge of 2 -inch PVC <br />casing at the cross -over has been pulled up about 46 feet and the camera was unable to enter the <br />2 -inch casing after this point. The video revealed that the 2 -inch casing had broken at depth, <br />rendering the well inoperable. Attempts to cement and rehabilitate the well were suspended at <br />this time. This well will need to be abandoned in the future. The well completion diagram is <br />presented in Appendix A. <br />November 2014 HydroGeo, Inc, <br />