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c involve the Pine Gulch drainage, it is not anticipated that mining in the area will affect the possible alluvial valley floor at Hay Gulch. However, final determination will be made by Colorado MLRD • during the review of the lessee's permit application for the lease application area. GEOLOGY AND MINERAL RESOURCES The only known mineral resource contained in the lease application area is coal. The coal deposits occur within the Menefee Formation of the Cretaceous Mesa Verde Group and is within the Durango Known Recoverable Coal Resource Area (KRCRA). National King Coal is the only operating mine in the area at this time. There are no known oil and gas deposits in the proposed lease area. However, oil and gas is known to occur in the Point Lookout, Gallup, Dakota Sandstone and the Paradox Formations. The tract is characterized by hilly plateau tops cut by several drainages. The altitude ranges from about 7,480 feet near the southeast corner of the lease application area to about 7,700 feet near the northeast corner of the lease application area.. The geologic formation outcropping on the tract is the Cliff House Formation of the Cretaceous Mesa Verde Group and the overlying Quaternary alluvial deposits. The coal proposed for mining is coal bed 1 in the Menefee Formation which outcrops a short distance north of the lease application area in the Hay Gulch drainage. No quantitative data exists for subsidence on the proposed lease area; however, the surface effects of subsidence have been recorded on Federal lease P-058300 approximately one-half mile northeast of • the tract. The overburden thickness ranges from 300 to 400 feet above coal bed 1 on the tract. Subsidence is directly affected by the thickness of the coal seam mined (4 to 6 feet), the overburden thickness, and overburden composition. A condition of approval of a mine permit for any successful bidder would be a requirement similar to that required by Colorado Mined Land Reclamation Division for National King Coal's Federal Emergency Lease C-29125. That requirement is that subsidence will be monitored on a quarterly basis. The monitoring would be to determine if any new subsidence is occurring and if the Huntington ditch is being affected in any way. The last report of 1988 by Cliff Schmid, Registered Land Surveyor and Fred M. Johnson, Certified Geologist indicates that no evidence exists of new subsidence and that the Huntington Ditch shows no evidence of being affected by underground mining. It is not anticipated that subsidence will affect thg proposed lease area. There are no active faults adjacent to or on the tract (Zapp, 1949). No other geologic hazards are known to exist. No known fossils of significance have been found on or near the tract. The Mesa Verde Group yields sparse faunas of both marine and non-marine elements. No study exists with specific reference to the botanical fossils related to the Menefee coals nor on the non-marine • invertebrates on the associated units (Fischer, 1981). 9