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Memo to Houlay Jumbo Mountain Landsliding page 7 stability of known landslide deposits to determine whether any reactivation were to occur. The Bear Mines and the West Elk Mine were both required to monitor known landslides adjacent to the town of Somerset. While these landslides subsided several feet no landslide translational reactivation has occurred. The Orchard Valley mine (Bowie #1) was required to monitor known landslides in Stevens Gulch and adjacent to its Portal facilities. None of these landslides evidenced reactivation. These same requirements have also been placed on underground coal and hardrock mines in other areas of the State of Colorado. To date, while they have been subsided, none of the monitored landslides have evidenced any reactivation. At the same time, every one of these mines has continued to evidence landslide occurrence, both in and outside subsided areas within the permit and adjacent areas. The North Fork Valley of the Gunnison River has evidenced periods of extensive landslide activity, in response to abnormal meteorological conditions, specifically during 1983-1984, 1993-1994 and 1996-1997. I anticipate that if the E1-Nino related precipitation is significant in 1998, it will be an active landsliding period, as well. Based upon this experience, I conclude that subsidence does not appear to be a significant determinant in the reactivation or initiation of landslide activity. Land Use Implications of Landsliding The Jumbo Mountain north slope landslide complex is transected by the boundary between Gunnison and Delta Counties. The county line appears to bisect the Muffler Rock landslide scarp. To determine the County land use designations for the property in question, Mike Boulay of the Division contacted the Planning Directors for both Delta County (MS. Barbara Ball) and Gunnison County (Ms. Joanne Williams). In Delta County there are no zoning requirements or land use designations. However, there are special zoning districts, but none of the Mautz property is located within any of these areas. There are no zoning designations in Gunnison County either. Joanne Williams determined that the Mautz property is designated as an "agricultural use by right" in Gunnison County. Page 2.04-4 of the West Elk permit application states that the pre- mining land uses on private lands within the permit area include cattle grazing, wildlife habitat, and dispersed recreational activities (hunting, trapping, off-road vehicle use). In addressing its proposed post-mining land uses on page 2.05-95 of the permit, MCC states "it is desired to provide final reclamation of the disturbed areas that is self-sustaining and provides habitat suitable for domestic livestock and wildlife".