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• WATER INFORMATION EXHIBIT G <br />• <br />• <br />1. Surface Water <br />The pits from this operation lie on the south side of the Colorado River. All pits will be allowed <br />to fill once mining and reclamation has been completed. Controls for both surface and <br />groundwater are included in this plan. <br />Surface water exists in two forms in this pit. The river runs to the north of the Scott Pit. A <br />minimum buffer of 100 feet will be maintained between the river and all top edges of mining <br />areas. This buffer will provide a sufficient safety factor against river capture, since there is no <br />outside bend of the river through this area which could be erosive. The Huddleston-Berry report <br />in Appendix D confirms this. <br />The second form of surface water will be storm and process water discharge. Substantial water <br />will be discharged throughout the mine life. Pumping will occur continuously for the life of the <br />mine. Pumping will occur in at least one of the mining areas of the Scott Pit. At times, two areas <br />may be pumped to provide access to both. Pits will be pumped by allowing water to drain <br />through dewatering trenches located around all or portions of the pit perimeter. Gravel filters <br />may be used in these trenches to reduce sediment prior to pumping. Water will discharge into the <br />Colorado River from Mining Area 1 and into the oxbow channel wetlands from Mining Area 2. <br />The discharge into the wetlands will help offset the water draw down caused by the pit <br />dewatering. All planned discharge points will be included in the storm and process water <br />discharge permit. This permit strictly regulates the pit discharges and it is required that total <br />suspended solids in the discharge be 35-70 milligrams per liter which is much lower than the <br />river is, which can flow in the hundreds and thousands of milligrams per liter during spring thaw <br />and rain events. <br />The following scenario is the expected dewatering plan for the Scott Expansion. This plan may <br />change due to unexpected hydrological conditions. <br />Scott Pit March 10 <br />G-1