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Past monitoring of the alluvium of Rapid and Cottonwood Creeks has not detected any significant <br />depletion of alluvial water in either creek system, and no significant depletion is anticipated. <br />There is no beneficial use of the groundwater in the mine permit area or vicinity. Mine inflow <br />quantity has been documented in past Annual Hydrology Reports. It has been demonstrated that <br />most of the mine inflow waters originate in the new faces of virgin coal seams. As these seams are <br />mined, the coal seam aquifer is dewatered. New areas of the mine have a higher inflow rate than <br />older, developed ones, which dry out after the area has been developed. Additional water originates <br />from the Mesaverde sandstone lenses as they are dewatered by mining activity combined with <br />subsidence. <br />The operator has committed to a mitigation contingency plan for downstream users should they be <br />effected by subsidence. <br />Groundwater Quantity: Effect on the Colorado River Alluvial Aquifer <br />Water quantity in the alluvium of the Colorado River aquifer is minimally affected by the mine <br />operations. The quantity of surface water and groundwater in the Roadside North and South Portal <br />facility areas and adjacent areas will not be adversely affected due to the recycling nature of the <br />ground and surface waters in the alluvial valley floor. Mining did not occur beneath the Colorado <br />River alluvial valley floor. Groundwater inflows to the South Mine workings discharge by gravity <br />flow through a dewatering pipe near the reclaimed North Decline, at Discharge Site 016, into the <br />Colorado River. Approximately 0.7 cfs of mine water is discharged into the Colorado River. <br />33 <br />