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Additional Comments on the Mesaverde Group The Mesaverde group consists of the Williams Fork and Iles Formations. Of these two members, only the Iles Formation is of interest in Sunland's permit and adjacent area. The ~illiams Fork Formation (and the Trout Creek Sandstone immediately below it) has been completely eroded off our permit area. The Mesaverde Group conformably overlies the Mancos and consists of the Iles and Williams Fork Formations, both of which are Upper Cretaceous in age. The Iles Formation is approximately 1500 ft thick and is composed of sand- stone, shale, and coal. The base of the Iles is generally defined by the Tow Creek sandstone member, a light brown, fine grain, well sorted sandstone. The Mancos - Iles contact in this area is identified as the base of the first sandstone above the predominance of shale. No holes were drilled by Sunland to a depth to reach this contact. However, seventy three feet of continuous sandstone was drilled at the bottom of hole EF-3 and a core was removed for analysis. This is the deepest sandstone member reached by Sunland's drilling, which is still some distance above the Tow Creek. This drill hole was off our permit area on Energy Fuels leasehold, approximately 5900 ft horizontal distance from the point of deepest projected penetration into the lower pinnacle seam by the No. 2 Mine. The core analysis (see page 60) indicates that this sandstone is a very poor aquifier. The Iles contains several massive sandstones that are similar lithologically to the Tow Creek. They include the Double Ledge Sandstone, the Oak Creek Sandstone that has the pinnacle coals associated with it, and the Trout Creek Sand- stone at the top of the formation. The shale between these sandstones is of marine orgin, is light to medium grey in color and tends to include progressively greater amounts of silt and fine sand in an upward direction. Sandstones within the Iles are thought to represent beach, delta front . and shallow marine environments. The coarsening upward shale is thought to indicate a trend toward transgression of the sea across the land. The data represented on page 25.2 represents depths and strata reached in hole 41SL-21 with the aforementioned sandstone correlated back to SL-21 collar elevation from EF-3 Rev 05/01/81 25.1