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West Elk Mine • Tremors generated by bumps and rock bursts in the Somerset Mine area attain magnitudes that have shaken structures in the West Elk Mine area and have been felt sometimes by West Elk Mine personnel. These local tremors may affect underground workings, landslide or potential rockfall areas, particulazly during prolonged periods of increased precipitation. It is noteworthy, however, that the Rulison nuclear shot in 1969, which produced a tremor with a Richter magnitude of 5.2, was many times greater than the magnitudes of any recorded coal bump. To Mr. Dunrud's knowledge, the Rulison nucleaz shot did not trigger any known landslides, rockfalls, did not affect the Somerset Mine, neither did it impact reservoirs, ponds, nor streams in the South of Divide mining area. Detailed Description of Damane or Diminution of Reasonable Use Which Could Result from Subsidence Related Phenomena 2.05.6/6)/e)(ii)/A-C) Based upon the anticipated subsidence phenomena previously described in this section, and the general lack of structures and renewable resource lands, MCC and W WE conclude that there will be little, if any, damage or destruction of reasonable use within the MCC permit area. The "worst possible consequence" to the newer, wood-framed buildings and livestock enclosure would be complete destruction. The building that is apparently utilized as seasonal sleeping quarters for cattle operations and hunting was constructed after the SNW longwall panel was developed and longwall mining in this panel had begun. The smaller "bunkhouse" building and • livestock enclosure were constructed after longwall mining was complete in both the SNW and 6NW longwall panels. They aze located approximately over the eastern-most pillar of the SNW longwall panel headgate, near cross-cut #17 and approximately 90 feet southeast of monitoring well SOM C-72H. The landowner had been provided updated mine plans in December 1993, and thus, was aware that mining would occur under the site. Subsidence impacts in the vicinity of theses structures were projected, based on a conservative twenty-five degree (25°) angle-of--draw and an overburden depth of approximately 800 feet. Mining in the B Seam occurred in the vicinity of the building in late November 1994 and had progressed two cross-cuts past it by late December 1994. The building and site were measured, surveyed and photographed in early November 1994, prior to possible subsidence impacts. Subsequent surveys and photographic records were begun in eazly December 1994, and were continued approximately weekly until January 1995, then bi-monthly through March 1995, when mining of the panel was completed. Regulaz monitoring (weekly, then bi-monthly, as above) were conducted when the 6NW longwall panel was mined past this azea. Maximum subsidence, as presented in Exhibit 60, is not expected at this location, but maximum stresses are anticipated, as the building is located at the edge of the panel. Because MCC will compensate for, repair or replace the building in compliance with CMLRB Rule 4.20.3(2), no material subsidence damage will result, as defined by CMLRB Rule 2.05.6(6)(e)(ii)(A). The "worst possible consequences" from mining to hydrologic resources, hydrology monitoring stations, and the many trails and unimproved U.S. Forest Service roads could be complete loss of surface water resources to the mine workings, total destruction of the stations and total destructlon 2.05-143 Revised November 2004 PRIO