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West Elk Mine <br />the continuous deformation zone these units undergo continuous flexure (Figure 2, enlargement 2 of <br />Exhibit 60B). Above the neutral surfaces, in zones of convex-upwazd curvature, the material is in <br />tension and below them, the material is in compression. <br />Consequently, stresses change across neutral surfaces from tension to compression with each <br />successive rock unit that deforms as a plate. Fractures already present would thus tend to open <br />more in the zones of tension and close more in the zones of compression, which would close these <br />fractures more than they were prior to mining and subsidence. <br />After longwall mining is completed in the area and static conditions aze attained, the zones of <br />tension and compression commonly cease, and any fractures present will likely resume the pre- <br />mising condition. Therefore, the impacts on surface flow in the drainage of the South of Divide <br />mining revision area aze likely to be minimal or non-existent under even the most conservative <br />assumptions. <br />Water and Methane <br />Observations of the north and west flanks of Mt. Gunnison during an October 1996 field trip, <br />revealed numerous talus and rock glacier deposits that occur in the valleys and lower part of this <br />intrusive body. Snow melt and rain can easily infiltrate these deposits, which may eventually enter <br />any permeable rocks, faults, fractures, and joints neaz the mountain. Coal beds and rocks in the <br />deformed zone around Mt. Gunnison might also contain increased methane where the coal is <br />metamorphosed to a higher rank by the intrusive body. Great quantities of water and methane may <br />therefore be expected as coal is mined closer to Mt. Gunnison. <br />Water and Met/:ane in the Oliver No. 2 Mine <br />Because lazge quantities of water and methane were encountered while mining the E/DO Seam in <br />the Oliver No. 2 Mine, other sources may also be present in the Box Canyon mining area. In the <br />report on the closure of the Oliver No. 2 Mine, large volumes of water and methane began to flow <br />from fractures in the floor of the southernmost (top) entry of 6a' East. The mine was evacuated and <br />closed because the water and methane flowed in quantities too costly to control. This area where <br />the lazge outpouring of water and methane occurred is located about 300 feet south of entries of the <br />South Mains that were not driven further, apparently because of roof control problems. <br />Water and methane intmsions were also common at least three yeazs before the mine closure. In a <br />letter to the Director of the Bureau of Land Management (BLM) on January 25, 1950, the president <br />of Calumet Fuel Company described the following conditions in the Oliver No. 2 Mine <br />(unpublished letter written to BLM Director Marion Clawson by Claude P. Heiner, January 25, <br />1950): <br />1. In October 1949, water seeped into the 3`d West entries from Sylvester Gulch, as the entries <br />were driven beneath the gulch. The water softened the entry floors and caused the roof to swell <br />and cave. Mining was halted because of mining problems (it became impossible to operate the <br />mobile loaders and shuttle cars) and to protect the miners. <br />2.05-127 Revised November 2004 PRIO <br />