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Mr. James Pendleton August 30, 1983 Page 4 • 4) F seam top of coal structure contours: The de- pressed contoured area beneath the sandstone is an indicator of compaction due to loading by the sandstone mass. 5) Oxidized coal and iron staining: The observed areas of oxidized coal beneath the fractures (re: microfractures?) serve to provide evidence that movement of water has persisted for a notable geologic time. The runoff season of 1983 was one of the heaviest on record, and no inflows were observed in conjunction with the fracture zones. (It should be noted that a locally re- charged flow was observed in another area of the mine; however, the flow rate was so low as to require only intermittent pumping). It may be stated that the oxidation has occurred as a slow process. 6) Fractures below the sandstone: There is no reason to believe that the coal and the mine floor were never fractured; however, evidence • of fracturing in the coal has been largely de- stroyed by oxidation, but in the few cases where fractures are visible, they simply appear as the same type of fractures as those produced in the brittle, low-tensile strength, sandstone. The underclay would most likely deform plastically-- possible resulting in a few additional slips or extending movements on ones which existed pre- viously. Conclusions: The hypothetical development sequence presented in this letter documents a series of events which would result in fractures of the character ob- served in the Mt. Gunnison No. L Mine. These fracture zones represented a hindrance during the production but have not presented a~ hazardous conditions since the face has passed through the area. Monitoring has shown that there is no movement in these areas. Finally, the mine tour and partial geotechnical in- spection which was mutually arranged by the MLRD and West Elk Coal Company on August 31, 1982 concluded that the fracture zones were not the significant hazard that rumors had led uninformed parties to believe. It was, and continues to be, the position of West Elk Coal Com- pany that the fractures represented no hazard. The ex- • tensive work relating to the fracture zones has un- earthed no evidence to alter this position.