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Calamity Draw is not included in the above table since the spoil springs from both mine areas <br />will not enter this stream. This intermittent stream should not be affected in the long term by the <br />mining and reclamation operation. <br />Overall, the effects of the spoil springs are not significant to the waters downstream. <br />7) Effects of mining on the local geomorphology. Impacts from mining on the local <br />geomorphology will be long term, but appear to be of minimal significance. The reestablished <br />reach of the drainage running south into Pond 007 will result in a shorter, slightly steeper stream <br />channel. The potential for increased sediment loads in the drainage (once pond 007 is removed) <br />should be offset by the stable bank sides and the relatively small change in overall gradient. The <br />reclaimed land will be graded to enhance irrigation and restore similar drainage patterns to those <br />which existed on the area prior to mining. The increased runoff and consequent erosion potential <br />on disturbed basins in the mining area due to the temporary loss of topsoil structure should be of <br />minimal significance since all disturbed areas will be protected by a system of sediment ponds. <br />Contour ripping, mulching and revegetation have been demonstrated to minimize soil erosion and <br />will be used to mitigate the increased runoff potential until the topsoil structure is developed. <br />Irrigation will help this to occur rapidly. <br />8) Effects of sediment ponds on channel characteristics & downstream users. Potential <br />impacts of sediment pond 007 and the other future ponds on downstream users will involve <br />possible reductions in flow due to impounded water. The water augmentation plan discusses the <br />available water which will be used should impacts be identified. WFC currently has rights to a <br />sufficient quantity of water to supply all users associated with the mining activities, plus an <br />additional quantity of water that can be used to mitigate any impact to downstream users. <br />9) Effects of sediment pond discharge on surface water quality. The effects of sediment <br />ponds on surface water quality will be negligible because each structure has been designed to <br />minimize impacts to the hydrologic balance. The ponds involve such minor areas of disturbance <br />that chemical and sediment changes in the flows will be unmeasurable. <br />10) Effects of runoff from reclaimed areas on the quality of streamflow. Due to the relatively <br />small area of disturbance in the New Horizon 2 mining area, any reductions in runoff will have only <br />a minimal impact on streamflow quantity, as flow in Calamity Draw is dominated by irrigation <br />return flow. Decreased sediment loads predicated by SEDCAD+ indicate that reclamation <br />efforts conducted in the mining area will ensure that additional contributions of suspended <br />sediment in runoff from reclaimed areas will not occur. Effects of runoff from reclaimed areas <br />on the quality of streamflow. Based on past operating history at the Nucla Mine, no significant <br />trend toward higher concentrations of the selected parameters have been detected. In addition, <br />the pond discharge will be monitored in accordance with NPDES discharge limitations and any <br />July 2016 (TR -74) 2.05.6(3)-36 <br />