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Topography, Geology and Soils <br /> The permit area is located on level to gently rolling topography consisting of fine sand, which is <br /> wind-deposited material overlying weathered residual shale. The sand varies in depth from <br /> about 5 feet to 20 feet, is highly to moderately permeable, and is highly susceptible to wind <br /> erosion. The flat-lying Number 7 coal seam was overlain by 60-180 feet of overburden <br /> consisting of yellow-brown and gray to blue gray soft carbonaceous shale and clay interbedded <br /> with sandstone and shaley sandstone. At the base of the Laramie formation is the Fox Hills <br /> member, a cross-bedded gray to buff sandstone, which is slightly or well cemented. <br /> The pre-mining soil capability class is VIe for irrigated and non-irrigated Valent soils. Osgood <br /> soils have capability classes of IVe for irrigated crops and VIe for non-irrigated conditions <br /> Surface and Ground Water <br /> Because of the low relief and deep, well-drained soils, there is virtually no surface runoff. No <br /> streams, springs or seeps exist in the area. All water flows subsurface through aeolian deposits <br /> to Ennis Draw, a topographic swale (ephemeral drainage)located along the eastern boundary of <br /> the permit area. Ennis Draw appears to be a complex, braided, ancient stream bed that has been <br /> covered by windblown sand. The draw discharges several miles to the north into Box Elder <br /> Creek. <br /> Ground water moves laterally toward the northeast, and apparently discharges into the sands and <br /> stream deposits in Ennis Draw. <br /> At the time the mine was originally permitted, ground water in neither the coal nor overburden <br /> was known to provide a water supply for any purpose in the vicinity of the mine. Since that <br /> time, ground water is being drawn for industrial uses at the mine, and a number of other wells <br /> have been drilled in the vicinity of the mine (review of State Engineer Records). However, no <br /> adverse impact from the mine is expected, due to the geologic and hydrologic conditions of the <br /> site. <br /> Climate <br /> The Keenesburg Strip Mine is located in a"continental" type of climate, characterized by low <br /> relative humidity, a large amount of sunshine, light rainfall, moderately high winds, and large <br /> daily range in temperature. Some statistics for nearby Fort Morgan were found on the Colorado <br /> Climate Center web site: <br /> • From 2011 to 2020, the average annual maximum temperature ranged from 61.3 to 71.8 <br /> degrees Fahrenheit. <br /> • From 2011 to 2020, the average annual minimum temperature ranged from 30.9 to 43.0 <br /> degrees Fahrenheit. <br /> • From 2011 to 2020, the average annual precipitation ranged from 5.76 to 19.26 inches. <br /> 5 <br />