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-7- Surface Water, Mine Area The original Findings Document listed two non-quantifiable anticipated effects at the time of permit issuance. These concerns were: 1. The ionic balance of surface flow associated with the mine site would change from a calcium bicarbonate to sodium-bicarbonate/magnesium-sulfate type water; 2. sediment deficient waters released from sediment ponds rou]d result in excessive erosion proximate to the discharge point. Surface water quality data collected at and near the mine site indicate that the water types are experiencing a departure from baseline conditions. Predominant water types are sodium-bicarbonate and sodium-sulfate, while water samples which exhibit magnesium as the dominant cation are rare. The data collected demonstrates that the chemistry of the water is being impacted by mining operations, but not to the extent identified in the original Findings Document. Future mining activities rill continue to impact the surface water quality, and further degradation of the quality may be expected. fie predominant trend w11'I be toward a sodium-sulfate type water, with magnesium rarely predomt nati ng. Regarding concern 2 identified above, no Eats indicating that significant erosion below detention ponds, due to the release of sediment deficient rater, has been submitted. The use of velocity and erosion inhibitors mitigates this potentiai problem. This potential impact is no longer considered a concern. Quantifiable surface rater effects from rtning which were identified in the original Ftnding Document include a reduction to surface flow volume and an increase in dtssolred solids concentrations. Under the assumed taining scenario, Bolton Draw surface flow (annual yield) would be reduced by 28S because of pond detention during the •ining phase of the operations. Following reclamation (while regetatlon is still being established). surface flows would increase Dy 6Y of the annual yield. During operations, salt loading could occur at a rate of 90.5 kg/yr. In Bush Draw, sedloent pond detention would be 7'i of the annual yield, the post-reclamation increase 1s 1t of the annual yield. and salt loading could be at the rate of 1.5 kq/yr. M1111ams Drar would be subject to a 21S reduction in flow due to sediment ponds, a 2Z post-reclamation increase, and a salt loading of 21.4 kg/yr. In Sudduth Draw no additional sediment ponds would De buiit and the flow reduction would remain 3f, folToring reclamation floc would be Increased Dy lS,_.and_ anticipated salt loading rould_be 5.4 kg/yr.