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The stratigraphic unit of interest is the Upper Cretaceous Mesaverde Group. The lowermost member of the Mesaverde Group is the 300 to 400 foot thick Point Lookout Sandstone. The upper potion of the Point Lookout is a massive, white to buff cliff forming sandstone, while the lower portion becomes shaley, and grades into the underlying Mancos Shale. The Menefee Formation, which conformable overlies the Point Lookout Sandstone, is the coal bearing unit in this area. At the proposed mine site, the Menefee dips 3° to the southeast, and strikes N35°W. This formation consists of approximately 350 feet of interbedded sandstone, shale, carbonaceous shale, and coal. Two coal seams appear to be the most continuous units in the formation. The upper seam, which is the coal to be extracted, is about 5 feet to 6 feet thick at the Blue Flame Coal Mine site. Conformably overlying the Menefee Formation in the Durango area is the uppermost member of the Mesaverde Group, the Cliff House Sandstone. The 350 foot thick Cliff House is a grey marine sandstone interbedded with shale. The sandstones are typically lenticular, but may be locally massive, white the shales are generally barren of coal. Relatively young, unconsolidated alluvial/colluvial material, presumably Holocene in age, forms the surface of Hay Gulch, adjacent to the Blue Flame Coal Mine. This material is derived from erosion of the Middle to Upper Mesaverde Group in the immediate vicinity. Overlying the Menefee Formation at the mine site is a thin veneer of fine grained materials locally derived from erosion of the Menefee. No landslides or other mass movements have been identified within the elue Flame permit area. The National King Coal operation, adjacent to the Blue Flame Coal Mine, which extracts coal from the same seam Blue Flame proposes to mine, has performed geochemical sampling of the roof, floor and coal. Based upon the results of this analyses, the Division has determined that the only acid-forming or toxic material present is the coal itself. No waste material will be extracted from the mine; all waste will remain underground in the workings. The proposed operation is in compliance with the requirements of this section. V. Ground Water Hydrology -Rules 2.04.5, 2.04,7, 2,05.6(3) and 4.05. Ground water hydrology information may be found in the permit application in Section 2.04 and 4.05. Two aquifers have been identified within the area potentially affected by the Blue Flame operation: the Hay Gulch alluvial aquifer; and, the Point Lookout Sandstone. -$-