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There is no discharge of water into an underground mine [4.05.16 and 4.05,3(1)(f)]. <br />K. Stream Buffer Zones <br />There are no stream buffer zones [4.05.18(1)]. <br />L. Probable Hydrologic Consequences [2.07.6(2)(c)] <br />The Probable Hydrologic Consequences section of the original Findings Document stated that <br />mixing of ground waters of the Rollins Sandstone and Wheeler Coal was possible due to fracturing <br />associated with mine development. Only very minor, unmeasurable water inflow occurred in the No. <br />2 mine tunnel, and none in the No. 1 tunnel. This is due in part to the cessation of operations at the <br />site since 1987. Portals No. 1 and No. 2 were only partially drilled (613 feet and 576 feet <br />respectively) into the Mancos shale. Therefore, it is highly unlikely that the tunnels modified the <br />groundwater conditions. <br />Another predicted impact of the Coal Ridge No. 1 operation was water quality degradation (due to <br />natural seeps Found in the azea) associated with the refuse disposal area. This impact never occurred <br />because the refuse pile was never constructed. <br />Due to minor fracturing within the Wheeler coal seam and the Rollins sandstone, there was some <br />potential that ground water could cross-communicate between these two seams. However, neither of <br />these rock units are utilized for ground water within the vicinity of the mine and, due to the extreme <br />dip of the bedrock, development of water from these seams outside the permit azea would be <br />economically prohibitive. For these reasons, significant impacts to ground water quality and quantity <br />in bedrock from mining at the Coal Ridge No. 1 Mine were not expected to occur. Additionally, <br />mining never advanced to the Wheeler seam, so additional fracturing of the Wheeler did not occur. <br />The alluvium in the mine area is rechazged from contact with surface water of the Colorado River <br />and its tributazies, and from upland sheet flow and snow melt. The alluvial bodies adjacent to the <br />Colorado River will release water back to the surface water system during periods of low flow. <br />Therefore, any impacts to the alluvial ground water would also have had the potential to impact the <br />quality or quantity of water within the Colorado River. <br />The subcrop of the Wheeler seam is located approximately 55 feet above the alluvium and dips <br />steeply away from the alluvial body. Undermining ofthe alluvial body did not occur during the life <br />of the mine. Therefore, dewatering of the Wheeler seam due to mining is not an expected impact to <br />the alluvium or surface water system of the Colorado River. (For further information see Alluvial <br />Valley Floor, Section IX of this document.) <br />Actual operations for the Coal Ridge No. 1 Mine included only minor disturbance on the surface, and <br />developmental work for two portals. The surface disturbance totaled approximately 35 acres. NCIG <br />constructed drainage control structures which treat runoff from 50 acres, only 35 of which were <br />disturbed. Runoff from the maj ority of the azea (35 acres) is treated prior to release in Sediment Pond <br />A. There aze 13 acres which include undisturbed azea and small disturbed azeas which have been <br />designated as alternate sediment control azeas, where runoff is detained in catchment sumps and <br />filtered prior to dischazge. <br />19 June 1, 2006 <br />