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West Elk Mine <br />If surface cracks were to form and if they were to intercept stock ponds or ephemeral channels, they <br />could potentially intercept surface water. Field evidence at the Section 17 cracks, evaluation of the <br />soft plastic shales occurring in the Barren Member above the F Seam, and theoretical subsidence <br />stress-strain relationships discussed elsewhere in the subsidence section of the application, each <br />strongly suggest that surface cracks would not extend to any great depth. <br />Two factors will also tend to heal the cracks, if they were to intercept water. First, the shales of the <br />Mesaverde Formation are known to have shrink-swell capacity. If the saturation of these shales <br />were to be increased, they would swell and this could be expected to help heal the crack. Secondly, <br />Mr. Jeff Hynes of the Colorado Geological Survey (1994) has stated that a greater factor in crack <br />healing would be increases in the plasticity of the shales as water saturations were increased. Simply <br />stated, as the shales become wetter, they soften and will squeeze into and heal the cracks. <br />An important consideration regazding mining in the Apache Rocks and South of Divide permit <br />revision areas are potential impacts to the Minnesota Reservoir. The water rights implications of <br />mining in the tributary azea to the reservoir are discussed later in Section 2.05.6 (3)(b)(iii & viii) <br />Water Rights. MCC has committed to maintaining a buffer zone between active mining and the <br />dam of over 1,000 feet, which is greater than the distance utilizing the conservative angle of draw <br />25 degrees. With a setback of this mazgin, there is no risk of either a crack developing under the <br />reservoir or aggravation of the existing structural problems with the dam as a result of MCC's <br />mining activities. Mining of longwall Panel 13 in the B Seam occurred at a distance of <br />approximately 700 feet from the reservoir with no adverse impacts to the structure. The <br />additional distance for longwall Panel E9 is very conservative given that the E Seam is <br />stratigraphically higher and, therefore, has a smaller area of influence at a given angle of <br />draw. <br />Wetlands <br />Based upon inspection of conventional and infrared aerial photographs and reconnaissance-level <br />field investigation, the wetlands in the permit azea aze confined primarily to manmade stockponds in <br />the drainages. They are intermittent in nature. Very few "natural" riparian wetlands are evident. <br />The total acreage of potential jurisdictional wetlands in the pemut area is approximately 7 acres (as <br />defined by the U.S. Army Corps of Engineers (USAGE)). Field surveys conducted in August 1995 <br />verified this estimate. An additional 2 to 3 acres lies above the l ONE and 11 NE longwall panels. <br />Field surveys in the South of Divide permit area in 1996 found additional wetland/riparian <br />areas along the valley bottoms within the Dry Fork and Lick Creek drainages and in <br />association with hillside spring and seeps (refer to Section 2.04.10). Another study was <br />conducted November 2004 showing these additional wetland areas and is included in Exhibit 32B, <br />Drawing 1. <br />Although most of the wetlands are found in drainage channels, there are small, isolated wetlands on <br />the hillsides where springs and seeps emerge. There aze other isolated wetlands in association with <br />landslides and slumps. In these instances, the wetlands are associated with the uppermost portion of <br />the landslide/slump, where a relatively flat area has been created and water has tended to collect and <br />saturate the soils. <br />2.05-107 Revised June 1005 PR/0; Rev. March 1006; Rev. Apri12006 PR/0; May 1006 PRIO <br />