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The Upper Pictured Cliffs Sandstone is a white to light gray, well sorted sandstone within <br />S thin interbeds or lenses of clay shale or siltstone. The sandstone is usually fine to <br />medium grained with a high percentage of quartz (85 % +) and very hard. The average <br />thickness of the Upper Pictured Cliffs is 120 feet. <br />Fruitland Formation (Kf Upper Cretaceous) The Fruitland Formation consists of a <br />sequence of complexly interbedded sandstone, siltstone, shale coaly shale and coal. The <br />contacts between the lithologic stratums are arbitrarily chosen due to their gradational <br />contacts. A tongue of the underlying Picture Cliffs Sandstone wedges between the Lewis <br />Coal Zone and the overlying Carbonera Coal Zone in the Carbon Junction Mine area. <br />For the purpose of discussion, this tongue has been mapped as a part of the Fruitland <br />Formation. A more detailed description of the stratum zones slated for disturbance by <br />surface mining occurs in the test borings section. The upper portion of the Fruitland is <br />gradational into the overlying Kirtland shale so the formational contact is arbitrarily <br />chosen. The average thickness for the formation is 700 feet. <br />Kirtland Shale (Kk Upper Cretaceous) The Kirtland Shale is divided into upper and <br />lower shaley members and the middle Farmington Sandstone member. The lower <br />member is primarily gray to gray -green shale and sandy shale lithologically similar to the <br />upper portion of the Fruitland. The Farmington Sandstone member is primarily massive <br />to irregularly bedded sandstone with lenses of greenish shale. The upper member <br />consists of interbedded sandstone and shale. <br />• McDermott and Animas Formations Kma, Upper Cretaceous - (Lower Tertia <br />These formations are composed of andesitic debris ranging in grain size from boulder - <br />conglomerates to clay - shale. For the purpose of this study, the formations were not <br />separated. <br />Ouaternary Terrace Gravels (021, Qg2, 00 and Ogu Pleistocene) Terrace gravels <br />related to the Pleistocene glaciation occur as widespread sheets in the Durango area. <br />Within the Carbon Junction Mine area, three levels of terrace gravels have been outlined <br />and mapped. The oldest terrace gravel is Qg1 on the map, Qg2 and possibly Qgu as the <br />next oldest and Qg3 as the youngest. Lithologically, these units are quite similar with <br />quartzitic and gneissic boulders and cobbles contained in a clayey silt -clay matrix. The <br />thickness of these individual units vary from 0 to 100 feet. <br />The contacts between the various terrace gravels are generally undefined and without a <br />distinct contact. The terrace gravels were deposited by glacial action over many years. <br />Thus the contacts have been subject to the weathering and erosional effects of the <br />environment at the time of deposition. Occasionally the contact between any of the <br />terrace gravels may be referred to as "slumping contacts ". The slumping contacts found <br />on the Carbon Junction Mine property are typical of those found in the general glacial <br />deposition of the region. The contacts are stable transitional zones and do not form <br />slipping planes or other contacts which have a tendency to be unstable. Roads, buildings, <br />or other structures placed on the contacts do not have stability problems due to the <br />integration of the materials in the transition contacts. <br />Abridged Permit Document 49 Feb 2008 <br />