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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 would 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 will continue to impact the surface water quality, and further degradation of the quality may be expected. The predominant trend will be toward a sodium-sulfate type water, with magnesium rarely predominating. Regarding concern 2 identified above, no data indicating that significant erosion below detention ponds, due to the release of sediment deficient water, has been submitted. The use of velocity and erosion inhibitors mitigates this potential problem. This potential impact is no longer considered a concern. Quantifiable surface water effects from mining which were identified in the original Finding Document include a reduction in surface flow volume and an increase in dissolved solids concentrations. Under the assumed mining scenario, Bolton Draw surface flow (annual yield) would be reduced by 28% because of pond detention during the mining phase of the operations. Following reclamation (while vegetation is still being established), surface flows would increase by 6% of the annual yield. During operations, salt loading would occur at a rate of 90.5 kg/y r. In Bush Draw, sediment pond detention would be 7% of the annual yield, the post-reclamation increase is 1% of the annual yield, and salt loading would be at the rate of 7.5 kg/y r. Williams Draw would be subject to a 21% reduction in flow due to sediment ponds, a 2% post-reclamation increase, and a salt loading of 21.4 kg/y r. In Sudduth Draw no additional sediment ponds would be built and the flow reduction would remain 3%, following reclamation flow would be increased by 1%, and anticipated salt loading would be 5.4 kg/y r.