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All of these acreages reflect the conditions of the site prior to the boundary change of TR -42. <br />After TR -42 (which removed 57.1 acres from the permit area when it was finalized on July 5, <br />2011), the total acreage was reduced to 555.4 acres. The other values do not change, because the <br />area removed with TR -42 was all non - disturbed land or land that has been Phase III released. <br />3.2.3 Resource to be Mined <br />Currently, there is no coal extraction activity at the site and none is anticipated. The open pits are <br />being backfilled with mine waste rock and ash imported from the Trigen Colorado Steam and <br />Electric Plant in Golden, Colorado and reclaimed in accordance with the reclamation plan <br />described in the Permit. During active surface coal extraction, the Number 7 seam of the Laramie <br />formation was mined. <br />3.2.4 Geology, Soils and Topography <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 about <br />5 feet to 20 feet, is highly to moderately permeable, and is highly susceptible to wind erosion. <br />The flat -lying number 7 coal seam is overlain by 60 -180 feet of overburden consisting of yellow - <br />brown and gray to blue gray soft carbonaceous shale and clay interbedded with sand and shaley <br />sand. At the base of the Laramie formation is the Fox Hills member, a cross - bedded gray to buff <br />sandstone, which is slightly to well cemented. <br />3.2.5 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 to <br />Ennis Draw, a topographic swale (ephemeral drainage) located along the eastern boundary of the <br />permit area. Ennis Draw appears to be a complex, braided, ancient stream bed that has been <br />covered by windblown sand. It discharges several miles to the north into Box Elder 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 time, <br />ground water is being drawn for industrial uses at the mine, and a number of other wells have <br />been drilled in the vicinity of the mine (review of State Engineer Records). However, no adverse <br />impact from the mine is expected, due to the geologic and hydrologic conditions of the site. <br />6 <br />