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<br />a paralithic clay shale - sandstone - carbonaceous shale - rock outcrop <br />complex. <br />The paralithic material is unsuitable for reclamation purposes; all other <br />mapped soil units have suitable topsoil material with recommended stripping <br />depths ranging from 5 to 56 inches. <br />The east side of the permit area is dominated by a mountain shrub plant <br />community, with Gambel's Oak being the predominant species. The predominance <br />of Gambel's Oak is expected in this area given past disturbances, elevation, <br />moisture and exposure. A small portion of the permit area is introduced <br />pasture and utilized by the landowner for grazing purposes. <br />The west side of the permit area, which includes the Barren Ridge and Federal <br />Lease Areas, is dominated by a sparse pinon-juniper plant community. The <br />dominant plants in this community are Gambel's Oak and pinon pine. Grasses <br />and fortis comprise less than 15 percent of the total vegetative cover in these <br />areas. <br />The permitted area lies on the northern rim of the San Juan Basin in <br />southwestern Colorado. The San Juan Basin is an asymmetric structural basin <br />containing sedimentary rocks ranging in age from Cambrian to Holocene. <br />Mining operations extracted the A, B, and C coal seams, which are located in <br />the Lower Fruitland Formation. The coal seams dip 6° to 8° to the southwest <br />and strike N 60°W. No large displacement faults exist in the permit area. <br />The A seam is the first minable coal seam encountered. It is generally four <br />feet to five feet thick with intermittent shale partings. The B seam is <br />located approximately 6 to 12 feet below the A seam and has an average <br />thickness of 11 feet. The C seam is located 20 to 30 feet below the B seam <br />and has an average thickness of 9 feet. <br />The Kirtland Shale overlies the Fruitland Formation. The Kirtland Shale is <br />composed of gray shales that contain thin layers of interbedded siltstone and <br />sandstone. This formation is highly erosive. <br />The streams in the area have eroded terraces in the Fruitland and Kirtland <br />Formations. These terraces were subsequently covered with alluvial gravels. <br />The Fruitland Formation is composed of interbedded sandstone, siltstone, <br />shale, carbonaceous sandstone, and siltstone, as well as the above-mentioned <br />coal seams. The coal seams appear to be the most continuous stratigraphic <br />units found within the Fruitland Formation. The coal-bearing zone is <br />approximately 82 feet thick. <br />Underlying the coal-bearing Fruitland Formation is the Pictured Cliffs <br />Sandstone. This formation is composed of white to yellowish-gray massive <br />sandstone ranging in thickness between 200 and 250 feet. The lower units of <br />the Pictured Cliffs Sandstone contain increasing amounts of shales. <br />The operator has performed both chemical analyses and leaching studies on <br />samples of the overburden, interburden and coal strata. Based on these <br />analyses, the Division has determined that there is no problem with <br />-4- <br />