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<br />United Compnaies, Inc. <br />February 15, 1994 <br />page 3 <br />uplift. Geologists feel that one or both of these rivers probably <br />flowed through Unaweep Canyon, a deep canyon (1000 feet or more) <br />that cuts right across the Uncompaghre Plateau. The present <br />Uncompahgre plateau became a distinct feature late in the Tertiary <br />time. Uplift was apparently so rapid as to change the river <br />course, through the soft Tertiary and Cretaceous shales. Much of <br />the erosion and sedimentation must have occurred in Ice-Age time <br />when runoff and stream loads were far greater than they are today. <br />Across the valley to the north and east lies the Bookcliffs which <br />are made up primarily of Mancos shale and capped with the Mesaverde <br />Group. The Mesaverde Group consists primarily of sandstone with <br />some lenses and layers of coal and shale. The Mesaverde Group, <br />Mancos Shale and Dakota Sandstone formations are all from the <br />Cretaceous Period. Below the Dakota Sandstone is the Morrison, <br />Summerville, Entrada and Kayenta formations of the Jurassic Period <br />over the Wingate Sandstone of the Triassic Period. <br />No geologic hazards such as rock falls, landslides or etc. exist at <br />the site. However, water from the Colorado River is very hard and <br />will flow through the site sand and gravel. The Billings soils <br />which largely came from the Mancos shale and the Mancos shale have <br />relatively high concentrations of sulfate and sodium salts. These <br />salts may produce corrosion of concrete or metal objects in contact <br />with the soil or rock. <br />Pursuant to CRS 34-32-115(4)(d) mining operations are to remain 200 <br />feet or more from any significant, valuable and permanent man-made <br />structures unless it can be demonstrated the mining operation will <br />not adversely affect the stability of those structures. <br /> <br />