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• In 1986 a debris flow at the site displaced the Bear Mine fan. In 1993 the area of the access road immediately below the fan slid, dropping the upper road approximately six feet. It is not known if the debris flows were reactivated by mining activity. Bear Coal Company will perform subsidence monitoring quarterly and will submit reports semi-annually. One of these reports will be the Annual Subsidence Report and will be submitted by Mareh 15 of each year. The study by Rocky Mountain Geotechnical indicates that mining of the C-Seam will result in propagation of fractures upward through the geologic section for approximately 360 fees. Strata between the C-Seam and the massive sandstone at the top of the lower coal bearing member will be rubblized to some degree. No rubbliTation of the overlying E- and F-Seams is expected to occur. Subsidence of the land surface is expected to a maximum of six to eight feet in We northwestern part of the mine. The permit application describes mining within the B- and C-Seams. Bear Coal Company has obtained the mineral rights to the overlying E and F coal seams, which occur from 180 feet to 410 feet above the C-Seam. Mining in these seams may significantly affect the surface and could have more significant subsidence impacts upon the existing landslide deposits. Significant consideration should be given to subsidence issues when mining of other coal seams in the area is proposed. • The mining operation is in compliance with the provisions of this section with the stipulations. XVI. Concurrent Surface and Underground Mining A. This section does not apply to the Bear Coal Company permit. XVII. Operations on Alluvial Valley Floors A. L~foimation describing alluvial valley floors (AVFs) in the study area is located in Section 2.06.8 of the Bear No. 3 permit revision application. The alluvial valley floor fmdings made by the Division for the Mountain Coal Company, West Elk Mine are directly applicable to the Bear Mine. The Bear No. 3 permit area and hydrologically adjacent areas were included in the Mountain Coal Company AVF survey area. No AVFs are located within the Bear mine permit boundary. The only part of the proposed permit or hydrologically adjacent area identified as alluvial deposits are adjacent to the North Fork of the Gunnison River. Several small bodies of alluvium lie along the course of the river between the mouth of Sylvester Gulch, immediately upstream of the Bear No. 1 portal and facilities • area and the town of Somerset. The reclaimed No. 1 portal and the area of the Bear No. 3 facilities both overlie alluvial material. Neither of these areas meets 32