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be siphoned into the cracks. The permittee predicted that the sediment <br />accumulating in the cracks and clay in the overburden would ultimately seal <br />the tension cracks from the surface inflow. <br />Continued monitoring of Red Wash has confirmed the permittee's <br />predictions. As projected, subsidence in Red Wash initially resulted in water <br />ponding in the stream-bottom. The high content of silt and clay carried by <br />Red Wash rapidly fills these stream-bottom ponds and seals any cracks that <br />formed in the alluvium as a result of the subsidence. Water continues to flow <br />in the surface channel at Red Wash while piezometric levels in the basal <br />alluvial gravel have dropped, indicating that the basal alluvium is not <br />recharged by surface flow infiltration. <br />Minimal subsidence impacts are expected in Scullion Gulch, similar to those <br />observed in Red Wash. The overburden under Scullion Gulch is less than <br />that of Red Wash. Tension cracks could cause several stock ponds in <br />Scullion Gulch basin. to lose impounded water. Although the stock ponds are <br />normally dry, a loss of water could occur where water is present as a result of <br />damage to the dams or pond bottom that would allow seepage loss. Prior to <br />the advancement of mining that could potentially impact the ponds, <br />monitoring is required to be initiated, and the ponds repaired or replaced by <br />the operator if water retention capability of the ponds is diminished due to <br />subsidence. The operator will haul water for stock in the event of pond repair <br />or construction. <br />2. Ground Water Impacts <br />The impact of the proposed mine on ground water will be localized, with no <br />significant impact expected on a regional basis. This is due primarily to the <br />small quantity of ground water in. the area. <br />Water encountered within the mine will be utilized underground for dust <br />suppression. As a result, only those inflows that temporarily exceed storage <br />capacities and mine use requirements would potentially be discharged to the <br />surface and lost from the ground water system. Pumping from approved <br />mine water discharge locations ceased upon the sealing of the D seam <br />northern longwall district in 1996). Although dewatering could be <br />accomplished by installation of a submersible pump, dewatering is not <br />currently anticipated. If mine water discharge were to occur, there would be <br />no loss to the hydrologic system, being that ground water in the area is <br />tributary to the White River. <br />Since January of 1997, prep plant thickener water has been disposed <br />underground within down-dip, sealed sections of the D seam mine. No <br />discernible effects on surface water or ground water quality are anticipated, <br />although water levels will be reestablished sooner than would otherwise be <br />the case. <br />Deserado Mine 34 June 18, 2009