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coal series is the D seam which ranges from 4.5 to 8 feet thick. Sixty to eighty feet below the D seam is the persistent Wheeler Seam, which is 15.5 to 22.5 feet thick. Exploration holes SK-12 and 13 penetrated a 7.5-foot-thick coal 80 feet below the Wheeler. To the west, this coal thins considerably (SK-10), but appears to thicken again in the vicinity of SK-gA, where it is 5 feet thick. The Lower Wheeler, identified on the western end of the property, is 15.5 to 16.5 feet thick and is 30 feet below the Wheeler. From subsurface information, the Lower Wheeler is most likely a split from the main Wheeler Seam. The Paonia member contains a three- to four-foot coal seam with one-foot riders that are lenticular throughout the property. This coal may thicken to the west where it has been reported to be 14 feet thick near New Castle. Above the Upper Sandstone, the A, B, and C seams have been correlated across the property with only moderate success. Although relatively thick, these coals are generally more lenticular and discontinuous. Wasatch and Ohio Creek Formations The Wasatch and Ohio Creek formations unconformably overlie the Mesaverde Group. These formations consist of red and buff shale, red sandstone, and red to gray conglomerate and form the ridge bluffs to the Grand Hogback. The upper part of the formations consist of red to buff soft shales with minor amounts of sandstone. The unconformity between the WasatchlOhio Creek and the Mesaverde makes it difficult to confidently project the coals of the upper units beneath the Wasatch/Ohio Creek for any great distance. Quaternary Deposits Quaternary unconsolidated sediments in the mine area, as represented by surface features, fall into three geomorphic categories: 1) Alluvium: These Quaternary deposits include all sediments associated directly with the active portions of the various stream channels and alluvial fans. Sediment size and thickness varies considerably between streams and within any one reach of a stream. 2) Terraces: Sediments associated with the inactive portions of the stream channels, particularly those at much higher levels, have been categorized as Quaternary Terraces. These terraces are most likely not associated with Pleistocene glacial deposits which are found at much higher topographic levels along the Colorado River. In some areas, particularly those areas extensively farmed, these deposits blend into the colluvial sediments, making it difficult to distinguish between the two geomorphic features. 3) Colluvium: colluvial deposits are considered to be loose, heterogeneous rock masses composed of soils and rock fragments which have been deposited chiefly by mass-wasting, usually at the base of steep slopes. Colluvium may also be deposited by unconcentrated surface runoff or sheet erosion, again usually at the base of a steep slope. In the permit area, -7-