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The King Coal Mine is located on the northwestern rim of the San Juan Basin. <br />The San Juan is an asymmetric structural basin in southwestern Colorado and <br />northwestern New Mexico. The basin contains sedimentary rocks ranging in age <br />from Cambrian to Holocene. The consolidated strata exposed in and near <br />Hay Gulch were deposited during the upper Cretaceous period. <br />The stratigraphic unit of interest is the upper Cretaceous Mesaverde Group. <br />The lowermost member of the Mesaverde Group is the 300 to 400 foot thick Point <br />Lookout Sandstone. The upper portion of the Point Lookout is a massive, white <br />to buff, cliff forming sandstone, while the lower portion becomes shaley, <br />grading into the underlying Mancos Shale. <br />The Menefee Formation, which conformably overlies the Point Lookout Sandstone, <br />is the coal bearing unit in this area. At the mine site, the Menefee dips 3° <br />to the southeast, and strikes N35°W. This formation consists of approximately <br />350 feet of interbedded sandstone, shale, carbonaceous shale, and coal. Two <br />coal seams appear to be the most continuous units in the formation. The upper <br />seam, which is the coal to be extracted, is about 5 feet to 6 feet thick at <br />the King Coal mine site. <br />Conformably overlying the Menefee Formation in the Durango area is the <br />uppermost member of the Mesaverde Group, the Cliff House Sandstone. The 350 <br />foot thick Cliff House is a grey marine sandstone interbedded with shale. The <br />sandstones are typically lenticular, but may be locally massive, while the <br />shales are generally barren of coal. This unit, however, has been removed by <br />erosion at the mine site. In its place is a thin veneer of fine grained <br />materials locally derived from erosion. <br />Recent unconsolidated alluvial/colluvial material forms the surface of Hay <br />Gulch, adjacent to the King Coal Mine. This material is derived from erosion <br />of the middle to upper Mesaverde Group in the immediate vicinity of the mine <br />site. <br />No landslides or other mass movements have been identified within the King <br />Coal permit area. <br />Based upon geochemical sampling and on-site observations, it appears that the <br />coal has some potential to he acid-forming or toxic-forming. Some coal waste <br />material is temporarily stockpiled on site prior to returning it to the <br />underground workings. Upon final reclamation some of this material will be <br />used to backfill the mine entries. This material will not impact the <br />post-mining land use or re vegetation efforts. <br />The operation is in compliance with the requirements of this section. <br />V. Ground Water Hydrology - Rules 2.04.5, 2.04.7, 2.05.6(3) and 4.05 <br />Ground water hydrology information may be found in the permit application in <br />Section 2.04 and 4.05. <br />Two aquifers have been identified within the area potentially affected by the <br />King Coal operation: the Hay Gulch alluvial aquifer; and, the Point Lookout <br />Sandstone. <br />-7- <br />