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the Phase II pit, it is likely that the dewatering affects from Phase II will not be extend beyond the permit boundary. 3.3 Mining Phase III For the Phase III pit dewatering analysis, a circular pit with a radius of 1,600 feet was used for the rectangular pit. Based on available information and parameter assumptions, the unobstructed radius of influence was estimated to extend approximately 3,500 feet beyond the pit wall (Figure 5) and mine dewatering flows of about 3,300 gallons per minute. Drawdown of the alluvial groundwater elevation is illustrated in Figure 6 and the spreadsheet analysis results are included in Appendix B. Similar to dewatering from the Phase I pit, the drawdown affects will be reduced by Arkansas River recharge and obstructions on the west side of the mine site. In addition to reclamation activities in Parcel 1 that influenced dewatering affects from the Phase I pit, during dewatering of the Phase III pit the Phase I pit will be reclaimed with a relatively impermeable clay liner. The result of these affects on the radius of influence has been estimated in Figure 5. Additionally, the drawdown affects north of the site will only extend to the alluvium boundary (Figure 5). Although Figure 5 and Figure 6 present estimates of potential dewatering impacts, alluvial groundwater elevation monitoring is recommended to evaluate actual impacts. Figure 6. Phase III Dewatering Curve a� 25 m 20 c Y 15 f- 10 N 5 'S 0 Q 0 2.000 4.000 6.000 8,000 Distance from Edge of Pit (feet) 4.0 GROUNDWATER MONITORING Groundwater monitoring and evaluation of potential dewatering impacts shall be conducted as part of a comprehensive groundwater monitoring plan prepared in accordance with requirements set forth by the Colorado Division of Reclamation, Mining and Safety for Amendment 01 to tblu e j(` h Page 9 of 11 SOLUTIONS