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Expert hydrologists and geologists have been instrumental in the preparation of this permit <br />document. These experts have provided accurate descriptive information related to the geology <br />and hydrologic systems for the area being affected over the estimated life of the mine. These <br />experts have utilized and, in some cases, collected the data to meet the requirements set forth by <br />the Division and these data are made available for public review and comment. <br />2.04.6 Geology Description <br />2.04.6(l) <br />The New Elk Mine is located in the Raton Basin, a crescent - shaped structural trough and <br />depocenter that extends from Huerfano Park, Colorado, to Cimarron, New Mexico. The basin is <br />bounded on the west of the Sangre de Cristo Mountains, on the northeast by the Apishapa Arch <br />and on the southeast by the Sierra Grande and Las Animas Arches. The basin is approximately <br />80 miles in length and 50 miles wide, encompassing approximately 4,000 square miles. The <br />basin is asymmetric in shape with the axis running along the western margin. The basin is filled <br />with approximately 20,000 to 25,000 feet of sedimentary rock in its deepest part. The Raton <br />Basin contains a large coal resource contained in Late Cretaceous and Paleocene formations. The <br />coal in the Raton Basin is well known for its high quality coking characteristics and coal bed <br />methane (CBM). The region is noted for its historical significance in coal mining and coke used <br />in once nearby steel mills. <br />The coal - bearing strata are underlain by Late Cretaceous sedimentary rocks of the Pierre <br />Shale and Trinidad Sandstone which are substantially below the coal seams planned for mining. <br />The Upper Cretaceous Vermejo Formation conformably overlies the Trinidad Sandstone. The <br />Vermejo Formation consists of interbedded gray to black carbonaceous, coaly and silty <br />mudstone and shale, slightly arkosic sandstone, carbonaceous siltstone, and numerous coal beds. <br />The formation ranges from 150 feet thick in the southern part of the basin to 410 feet thick in the <br />northern part of the basin. Within the proposed permit area and vicinity, the CBM industry <br />exploits gas from coals contained within the Vermejo Formation. <br />Overlying the Vermejo Formation is the Upper Cretaceous and Paleocene Raton Formation <br />which contains the coal seams of mining interest and of which New Elk Mine plans to extract by <br />underground mining methods. The Raton Formation contains a basal conglomerate that rests <br />conformably on the Vermejo Formation. Above this basal conglomerate lies interbedded <br />sandstone, siltstone, mudstone, and numerous coal beds. The basal conglomerate is extremely <br />variable in composition and varies in thickness from a thin edge near Trinidad to 250 feet near <br />the town of Stonewall. Above the conglomerate is an alternating sequence of greywacke, arkosic <br />and quartzose sandstone with interbedded siltstone, mudstone, and coal, which has been <br />subdivided into a lower coal zone, a barren zone and an upper coal zone. The lower coal zone <br />ranges from 100 to 250 feet thick and contains the famous Cretaceous/Tertiary (KIT) boundary <br />near the base as evident by a layer rich in iridium. The barren zone ranges from 180 to 600 feet <br />thick and the upper coal zone is about 1,100 feet thick in the center of the basin. Coal seams of <br />mineable interest to New Elk Mine, such as the Blue, Maxwell, Apache and Allen seams are <br />MR -99 2.04 -9 Revised 12/28/11 <br />