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West EJk Mine If surface cracks were to form and if they were to intercept stock ponds or ephemeral channels, they could potentially intercept surface water. Field evidence at the Section 17 cracks, evaluation of the soft plastic shales occurring in the Barren Member above the F-Seam, and theoretical subsidence stress-strain relationships discussed elsewhere in the subsidence section of the application, each strongly suggest that surface cracks would not extend to any great depth. Two factors will also tend to heal the cracks, if they were to intercept water. First, the shales of the Mesaverde Formation aze known to have shrink-swell capacity. If the satttration of these shales were to be increased, they would swell and this could be expected to help heal the crack. Secondly, Mr. Jeff Hynes of the Colorado Geological Survey (1994) has stated that a greater factor in crack healing would be increases in the the plasticity of the shales as water saturations were increased. Simply stated, as the shales become wetter, they soften and will squeeze into and heal the cracks. An important consideration regazding mining in the Apache Rocks permit revision area is potential impacts to the Minnesota Reservoir. The water rights implications of mining in the tributary azea to the reservoir aze discussed later in Section 2.05.6 (3)(b)(iii & viii) Water Rights. MCC has committed to maintaining a buffer zone between active mining and the dam of at least 700 feet, which is greater than the distance utilizing the conservative angle of draw 25 degrees. With a setback of this mazgin, there is no risk of either a crack developing under the reservoir or aggravation of the existing structwal problems with the dam as a result of MCC's mining activities. Wetlands ,~ Based upon inspection of conventional and infra-red aerial photographs and reconnaissance-level field investigation, the wetlands in the permit area aze confined primarily to manmade stockponds in the drainages. They aze intermittent in nature. Very few "natural" riparian wetlands aze evident. The total wetlands acreage in the permit azea is approximately 7 acres (as defined by the U.5. Army Corps of Engineers (USAGE). Field surveys conducted in August 1995 verified this estimate. An additional2 to 3 acres lies above the l ONE and 11 NE longwall panels. Although most of the wetlands aze found in drainage channels, there are small, isolated wetlands on the hillsides where springs and seeps emerge. There aze other isolated wetlands in association with landslides and slumps. In these instances, the wetlands are associated with the uppermost portion of the landslide/slump, where a relatively flat area has been created and water has tended to collect and saturate the soils. Impacts to wetlands are regulated under Section 404 of the Federal Clean Water Act. Section 404, and the accompanying regulations (including, in particular, the 404(b)(1) Guidelines) indicate that proposed activities which result in dredging and/or filling regulatory wetlands need to obtain a Section 404 permit prior to commencement of the activity. To qualify as a "regulatory wetland," the land in question must meet specific requirements pertaining to vegetation, soils and hydrology. As of Mazch 1995, the criteria for these three parameters were being closely reviewed by the U.S. Army Corps of Engineers (USAGE), U.S. Environmental Protection Agency (EPA), and a technical committee of the National Science Foundation. 2.05-167 Revised Jun. /995 PR06: Revised Nov. 1998TR80:1/98 PR08