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additional quantity of water that can be used to mitigate any impact to <br /> downstream users. <br /> Effects of sediment pond discharge on surface water quality: The effects <br /> of sediment pond diversions on surface water quality will be negligible <br /> because the structure has been designed to minimize impacts to the <br /> hydrologic balance. The diversion involves such minor areas of <br /> disturbance that chemical and sediment changes in the flow will be <br /> unmeasurable. <br /> Effects of runoff from reclaimed areas on the quality of streamflow: Due <br /> to the relatively small area of disturbance in the New Horizon 2 mining <br /> area, any reductions in runoff will have only a minimal impact on <br /> streamflow quantity, as flow in Calamity Draw is dominated by irrigation <br /> return flow. Decreased sediment loads predicated by SEDCAD+ indicate <br /> that reclamation efforts conducted in the mining area will ensure that <br /> additional contribution of suspended sediment in runoff from reclaimed <br /> areas will not occur. Based on past operating history at the Nucla Mine, <br /> no significant trend toward higher concentrations of the selected <br /> parameters have been detected. In addition, the pond discharge will be <br /> monitored in accordance with NPDES discharge limitations and any <br /> potential impact will be identified. Therefore, runoff from the reclaimed <br /> area should have no significant impact over time on the quality of <br /> receiving stream water quality. As a result, post mining land uses which <br /> currently occur in the area should not be affected due to the mine plan <br /> which has been approved. <br /> 2. All probable impacts have been determined to be of a short term nature, <br /> of minimal significance, or a plan has been presented to mitigate those <br /> determined to have some significance. As a result, mining affects to <br /> current land uses should be minimal. A detailed report is included in <br /> Section 2.04.7 and Table 2.05.6(3)-1 of the permit application. <br /> III. Topsoil <br /> A. The Division has determined that in a 15-acre parcel identified in Section <br /> 2.04.9, soil types from New Horizon 2's mine, the B horizon and portions of the <br /> C horizon shall be segregated and replaced as subsoil in order to ensure soil <br /> productivity consistent with the approved post-mining land use (4.06.2(3)). <br /> B. The Division has determined selected overburden materials shall be used for, <br /> or as a supplement to topsoil. The resulting soil is equal to or better than the <br /> available topsoil. This determination is based on physical and chemical <br /> analyses and field-site trials approved by the Division (4.06.2(4)(a)). <br /> 20 <br />