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_V411 ► <br /> 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. New Horizon currently has <br /> rights to a sufficient quantity of water to supply all users associated with the mining <br /> activities, plus an additional quantity of water that can be used to mitigate any impact to <br /> 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 /> January 2017 (TR-77) 2.05.6(3)-36 <br />