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°~ _ ~ ~- <br />III, Cultural and Historic Resources - Rules 2,04,4 and 2,05.6(4) <br />Information pertaining to cultural and historic resources is presented in <br />Section 2.04 (pages 2.04-6 to -g) and in Exhibit 10 of the permit application. <br />Contact with the State Historic Preservation Officer and a file search in the <br />State Archaeological Office indicates that there are no known cultural <br />resources or resources listed on the National Register of Historic Places <br />within the proposed permit area. <br />The applicant is in compliance with the requirements of this section. <br />IV, Geology - Rules 2,04,5 and 2,04,6 <br />Information pertaining to the geology of the proposed operation and adjacent <br />area is presented in Sections 2.04.5 (pages 2.04-9 to -14) and 2,04,6 (pages <br />2,04-14 to -16) of the permit application. <br />The La Plata No. 1 Mine is located on the northwestern rim of the San Juan <br />Basin. This basin is an asymmetric structural basin in southwestern Colorado <br />and northwestern New Mexico. The basin contains sedimentary rocks ranging in <br />age 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 shalely, <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 proposed mine site, the Menefee <br />dips 3o to the southeast and strikes N35oW. This formation consists of <br />approximately 350 feet of interbedded sandstone, shale, carbonaceous shale, <br />and coal. Two coal seams appear to be the most continuous units in the <br />formation. The upper seam, which is the coal to be extracted, is about 4 feet <br />to 6 feet thick at the La Plata No. 1 Mine site. The lower seam is <br />approximately 45 - 100 feet below this upper seam with a thickness varying <br />from 2 to 6,8 feet. This seam is not proposed to be mined at this time, <br />Conformably overlying the Menefee Formation in the Hesperus area is the upper <br />most member of the Mesaverde Group: the Cliff House Sandstone. This 350 foot <br />thick unit is a grey marine sandstone interbedded with shale. The sandstones <br />are generally lenticular, but may be locally massive, while the shales are <br />generally barren of coal. This unit has been removed by erosion at the mine <br />site. <br />Overlying the Menefee Formation at the mine site is a thin colluvial veneer of <br />fine grained materials locally derived from erosion. <br />Recent unconsolidated alluvial/colluvial material forms the Hay Gulch valley, <br />adjacent to the La Plata No. 1 Mine. This material is derived from erosion of <br />the middle to upper Mesaverde Group in the immediate vicinity of the mine site, <br />-10- <br />