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. in TDS. During March/April, the River is flowing fast and Tuttle Draw is at low flow, therefore the <br />increase in TDS for the River is only 2 ppm, or an increase of 0.4%. Also, these impacts are for the time <br />when the spoil material is leaching salts at a maximum. As described earlier, the TDS levels will drop <br />as pyrite and salts are leached out of the spoil, lessening the impact to the waters downstream even <br />further. <br />Calamity Draw is not included in the above table since the spoil springs from both mine areas will not <br />enter this stream. This intermittent stream should not be affected in the long term by the mining and <br />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 aeomorahology. Impacts from mining on the local geomorphology <br />will be long term, but appear to be of minimal significance. The reestablished reach of the drainage <br />running south into Pond 007 will result in a shorter, slightly steeper stream channel. The potential for <br />increased sediment loads in the drainage (once pond 007 is removed) should be offset by the stable <br />bank sides and the relatively small change in overall gradient. The reclaimed land will be graded to <br />enhance irrigation and restore similar drainage patterns to those which existed on the area prior to <br />mining. The increased runoff and consequent erosion potential on disturbed basins in the mining area <br />due to the temporary loss of topsoil structure should be of minimal significance since all disturbed areas <br />will be protected by a system of sediment ponds. Contour ripping, mulching and revegetation have <br />been demonstrated to minimize soil erosion and will be used to mitigate the increased runoff potential <br />until the topsoil structure is developed. Irrigation will help this to occur rapidly. <br />8) Effects of sediment oonds on channel characteristics and downstream users. Potential <br />impacts of sediment pond 007 and the other future ponds on downstream users will involve possible <br />reductions in flow due to impounded water. The water augmentation plan discusses the available water <br />which will be used should impacts be identified. WFC currently has rights to a sufficient quantity of <br />water to supply all users associated with the mining activities, plus an additional quantity of water that <br />can be used to mitigate any impact to downstream users. <br />91 Effects of sediment pond discharge on surface water quality. The effects of sediment ponds <br />on surface water quality will be negligible because each structure has been designed to minimize <br />impacts to the hydrologic balance. The ponds involve such minor areas of disturbance that chemical <br />and sediment changes in the flows will be unmeasurable. <br />• (Revised 6/01) 2.05.6 (3) - 37 <br />