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possible reductions in flow due to impounded water. The water augmentation <br />plan discusses the available water which will be used should impacts be <br />identified. WFC currently has rights to a sufficient quantity of water to supply <br />all users associated with the mining activities, plus an additional quantity of <br />water that can be used to mitigate any impact to downstream users. <br />Effects of sediment pond discharge on surface water quality: The effects of <br />sediment pond diversions on surface water quality will be negligible because the <br />structure has been designed to minimize impacts to the hydrologic balance. The <br />diversion involves such minor areas of disturbance that chemical and sediment <br />changes in the flow will be unmeasurable. <br />Effects of runoff from reclaimed aeeas on the quality of streamflow: Due to the <br />relatively small area of disturbance in the New Horizon 2 mining azea, any <br />reductions in runoff will have only a minimal impact on streamflow quantity, as <br />flow in Calamity Draw is dominated by irrigation return flow. Decreased <br />sediment loads predicated by SEDCAD+ and HEC 2 indicate that reclamation <br />efforts conducted in the mining azea will ensure that additional contribution of <br />suspended sediment in runoff from reclaimed areas will not occur. Based on past <br />operating history at the Nucla Mine, no significant trend toward higher <br />concentrations of the selected pazameters have been detected. In addition, the <br />pond dischazge will be monitored in accordance with NPDES discharge <br />limitations and any potential impact will be identified. Therefore, runoff from <br />the reclaimed azea 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 azea should not be affected due to the mine plan which has <br />been approved. <br />2. All probable impacts have been determined to be of a relative 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 current land <br />uses should be minimal. A detailed report is included in Section 2.04.7 and <br />Table 2.05.6(3)-1 of the permit application. <br />III. T~soil <br />A. The Division has determined that, for most soil types within the New Horizon 2 permit <br />area and the PR-OS revision area, lower portions of 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)). Salvage <br />of topsoil and subsoil in two separate lifts will be employed for all map units occurring <br />on irrigated pastureland and irrigated hayland. For these soils, the A horizon and <br />upper portions of the B will be salvaged in one lift, with lower portions of the B and <br />23 <br />