Laserfiche WebLink
Brooks Bridge gauge is up stream if site SW -N217 and the Uravan gauge is downstream of SW - <br />N218. <br />7) Effects Of Minim On The Local Geomorphology Impacts from mining on the local <br />geomorphology will be long term, but appear to be of minimal significance. The reclaimed land <br />will be graded to enhance irrigation and restore similar drainage patterns to those which existed <br />on the area prior to mining. The increased runoff and consequent erosion potential on disturbed <br />basins in the mining area due to the temporary loss of topsoil structure should be of minimal <br />significance since all disturbed areas will be protected by a system of sediment ponds. Contour <br />ripping, mulching and revegetation have been demonstrated to minimize soil erosion and will be <br />used to mitigate the increased runoff potential until the topsoil structure is developed. Irrigation <br />will help this to occur rapidly. <br />8) Effects Of Sediment Ponds On Channel Characteristics and Downstream Users Potential <br />impacts of sediment ponds on downstream users will involve possible reductions in flow due to <br />impounded water. The water augmentation plan (included in the Appendix 2.05.6(3) -lc to this <br />Section) discusses the available water which will be used should impacts be identified. NHN <br />currently has 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 sediment structure has been <br />designed to minimize impacts to the hydrologic balance. The ponds involve such minor areas of <br />disturbance that chemical and sediment changes in the flows will be immeasurable. <br />10) Effects of Runoff from Reclaimed Areas on the Quality Of Streamflow Due to the <br />relatively small area of disturbance in the NHN Mine area, any reductions in runoff will have <br />only a minimal impact on streamflow quantity, as flow in Tuttle Draw is dominated by irrigation <br />return flow. Decreased sediment loads predicated by SEDCAD (see New Horizon #2 Area <br />permit) indicate that reclamation efforts conducted in the mining area will ensure that additional <br />contributions of suspended sediment in runoff from reclaimed areas will not occur. Irrigation of <br />reclaimed area will utilize sprinklers instead of flood irrigation that should further reduce erosion <br />and sediment load. Based on past operating history at both Nucla Mine and the adjacent New <br />Horizon Mine, no significant trend toward higher concentrations of the selected parameters has <br />been detected. In addition, the pond discharge will be monitored in accordance with NPDES <br />discharge limitations and any potential impact will be identified. Therefore, runoff from the <br />reclaimed area should have no significant impact over time on the quality of receiving stream <br />waters. As a result, post mining land uses which currently occur in the area should not be <br />affected due to the projected mining plan. <br />Section 2.05.6(3) Page 29 April 2016 (PR -01) <br />