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<br />United Companies, Inc. <br />March 21, 1994 <br />Page 2 <br />Based on drill log data provided, ten drilled holes were spaced at <br />approximately 400 feet on centers. The logs indicate 1 to 4 feet <br />of fine grained overburden soils over the silty sand, gravel and <br />cobble (pit run) material. Drill holes extended to a depth of 25 <br />feet with no ground water being encountered. The drill holes did <br />not extend to a depth that encountered the underlying Mancos shale. <br />Per soil series maps the fine grained overburden soils classify as <br />Vernal clay loam, 0 to 2 percent slopes for the portion to be mined <br />and Uncompahgre loam for the northeast corner, approximately 4.3 <br />acres that will not be mined. The Vernal clay loam (VeA) consists <br />of a reddish brown clay loam overlying coarse sand, gravel and <br />cobblestones. The clay loam has a slow permeability and a moderate <br />organic content. The clay loam is generally 18 to 20 inches thick. <br />The lower sand, gravel and cobblestones have high permeability, are <br />not highly susceptible to erosion and the structure is stable. <br />The Uncompahgre loam, 0 to 2 percent slopes, is a flood plain and <br />low terrace soil. The upper 8 to 30 inches is a loam followed by <br />stratified sand, silt and clay lenses and layers, followed by the <br />sand, gravel and cobbelstones encountered at this site. <br />The sand, gravel and cobbles are classified in geologic terms as <br />Quanternary sediments which includes river deposits, landslide <br />deposits and rock glaciers or Ice-Age glacial debris. Other <br />geologic maps indicate the overburden materials as simply flood <br />plain deposits, primarily sand and gravel with significant fines. <br />Underlying the flood plain gravel (Quanternary sediments) is the <br />Mancos shale formation. The Mancos shale formation is from the <br />upper Cretaceous age and is made up of grey to yellow, marine <br />deposits. The Mancos shale was laid down in flat layers in a <br />Cretaceous sea, the shale is now tilted up south ward toward the <br />