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June 25, 2010 10 of 15 <br />Figure 5. Detailed Cross Section Showing Presumed Location of Drill Hole Through Upper <br />Mine Workings <br />Note that installing a pump in the exhaust borehole shown in Figure 4 is not feasible for several reasons. <br />Most importantly, the exhaust borehole deviates at least 3% from the vertical, meaning that a pump could <br />not be set vertically in the hole. If a pump column were to be lowered into the vent shaft, the pump, motor, <br />wiring, and discharge pipe would rub against the exposed rock in the vent shaft and be abraded and <br />damaged. It is highly unlikely that a pump system could be lowered one thousand two hundred and twenty <br />feet (1,220 ft) from the vent shaft opening on top of the hill to the 500 level in the mine. Experience has <br />shown that any deviation, seam, lip, or protuberance in a cased well can impede the lowering of a pump. <br />Also, the vent shaft was reclaimed at the surface in 2008, and is no longer accessible. <br />One might ask why installing pumps is such a difficult technical challenge today, when the mine was <br />successfully dewatered for over 40 years during operations. While the mine was operating, dewatering <br />occurred in stages as the mine was advanced. In the final years, at the maximum extent of the mine, water <br />was collected on the 19 Level, pumped to the 7 level, and then pumped to the surface. Piping was in place <br />to convey water up from the workings, out the Steve Level adit, to the water treatment plant. Those pumps <br />and piping are no longer in place, and the mine is flooded and inaccessible below the Steve Level.