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MINING PLAN <br />Third, installing a groundwater barrier wall near the beginning will prepare the site for a reservoir <br />use after mining. There is still considerable interest in such reservoirs, but purchasers appear to prefer <br />having a site that is already sealed rather than a site they have [o seal. <br />Requirement: A series of monitoring wells shall be maintained around the perimeter of the <br />operation to maintain a record of the impacts of the operation on the adjacent groundwater. <br />DISCUSSION: The ongoing monitoring program will further refine the dynamics of the <br />groundwater system and the effects of mining and dewa[ering. Thus the system of monitoring wells will <br />continue to provide a means [o see what effects are occurring. With the data generated by [he monitoring <br />program, if adjustments or corrective actions are needed, the information will be there to aid in <br />determining what course of action will produce the desired effects. <br />There is more information available on [his subject in Exhibit G -Water Information. <br />Dewatering of the Phases <br />PHASE 1: <br />Requirement: Dewatering and sediment control of Phase 1 shall be maintained in accordance <br />with the basic layout shown in Figure 1 in [his exhibit. The actual location and arrangement of <br />sediment basins and piped or pumped flows shall be at [he discretion of the operator in accordance <br />with the needs of the operation so long as the basic layout is followed. <br />DISCUSSION: In the original plan it was envisioned that astair-step sediment control system <br />would be established on the east side of the drainage next to the processing plan[. That was done, but it <br />didn't last long. I[ did get [he operation through the initial opening and processing of materials, but the <br />smallness of the system was soon overwhelmed. On the other hand, it worked very well so long as only a <br />small amount of material was processed, <br />A short while later, a new, in-pi[ sediment basin was constructed. After some initial problems <br />with leakage from [he structure, i[ was decided the berm had to be stronger and the current sediment basin <br />was constructed with essentially a compacted berm, keyed in at both ends. This has held admirably and <br />shows practically no leakage. This left [he water entering the pit from the edges in excellent condition. <br />Dewatering has been accomplished ever since by pumping the water across the ditch east of the plant to <br />the sediment control and settling circuit. The only problem with this is that the volume of water, as the pit <br />expanded, became greater and greater. <br />Pueblo East Pit Amendment 3 (2007) Exhibit D Page 19 of 34 <br />