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West Elk Mine have on the highway. Such monitoring will be accomplished by vertically driving steel rods into ~ the landslide area south of Highway 133 at locations potentially subject to reactivation. These aze then monitored by surveying to assess changes. Should movement be noted on these metal stakes, additional studies and surveys can be undertaken to assess where reactivation is occurring, the rate of movement, the area extent and depth of they materials that aze moving, and the potential for impact to the highway. It should be noted that the portion of longwall panel 18A that is closest to the highway (approximately 600 feet horizontal distance) includes development entries, which have the smallest subsidence potential because of the room-and-pillar mining techniques used. This development mining will occur before any longwall mining activities. When longwall mining occurs in panel 18A, it will be further south (about 250 feet) with an angle of draw that will not influence the landslide area. As a result, monitoring of the landslide during development mining will serve to assess the most likely potential reactivation period, particularly during spring runoff. Material damages created by the activation of the landslide, should they occur, are expected to be limited to the physical obstruction of traffic on Highway 133. As previously stated, it is anticipated that monitoring will assist in evaluating the potential for this occurrence and minimize the health threat to individuals driving on Highway 133. Should the landslide reactivate and threaten or cross Highway 133, MCC will provide available assistance in the clearing of the highway and mitigation of the effects. WWE fmds the likelihood of this occurrence to be extremely small except in abnormally wet conditions, which will have a similaz effect on numerous landslides throughout the North Fork Valley. Roc all - As discussed in Section 2.04.6, Geology Description, there aze exposed rock faces on steep slopes where the potential for rockfall exists within the permit azea. Theoretically, mining- induced changes in stress and strain and fracturing could trigger additional rockfall from the many sandstone cliffs. Areas of rockfall potential, such as the flanks of West Flatiron within the Apache Rocks and Box Canyon pernut revision areas, will be monitored for rockfall-whether it is naturally occurring or mining induced. As with landslides, due to the lack of structures and limited human activity within the permit area, present and future land use will not be significantly impacted. There aze no identified rockfall azeas within the West Flatiron lease azea, as shown on Map 1 of Exhibit 60C. Therefore, any possible subsidence-induced rockfall in the West Flatiron lease area should be of insignificant consequence. • 2.05-I05 Revised Jun. 1995 PR06;1/96 RN03; Revised May 1999 TR89;RevisedJmx 1998 PR08;Mnrch 2005 PR11 C ~'\~~'/