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RECLAMATION PLAN <br />reclaim while the operation is occurring, but it is still large enough that near the end of the mining, <br />backfilling of the areas away from the mining could occur. <br />The importance of prompt backfilling is apparent when one examines the adjacent river flow <br />patterns. If a major flood were to occur when the area is fully opened there is a slight possibility that <br />overflow could enter the pit and flood the entire operation. That is the purpose of the protective bamer <br />berm which elevates the overflow elevation to as much as four feet higher than it currently is. Once <br />backfilling is completed the protective barrier berm will no longer be needed and will be removed so very <br />high flood waters can flow over this area. A protective berm will remain in place around the main pit so if <br />flood waters flow over the Amendment 2 area they will not likely flow into the main pit. It is also important <br />to recognize that overflow through the Amendment 2 area has historically occurred during very high river <br />flows. However, it takes a major flow, probably in excess of 4000 cfs, to cause more than just some minor <br />overflow. <br />This provides the reason why this Amendment 2 area will primarily be operated in the winter and is <br />expected to be completed with mining and most of the backfilling by early June of the next season when <br />high runoff flows can occur. In this stretch of the river, the primary cause of high flaws comes from <br />Fountain Creek rather than the Arkansas River. Very heavy thunderstom~s in the Colorado Springs area <br />can result in very high flows in Fountain Creek and along the Arkansas downstream from Fountain Creek. <br />But Pueblo Dam highly regulates the Arkansas River contribution and it is not often that releases from <br />Lake Pueblo produce extremely high flows. <br />Post-Mining Land Uses <br />The post mining land use for the amendment area will primarily involve a replacement of the <br />riparian forest unit and habitat. Having forest in this area is very important to the overall condition of the <br />riparian corridor and maintaining a high degree of continuity in forest units along the river. <br />CHANGE IN ORIGINAL PLAN: After full consideration of the topographic and vegetation <br />impacts of the amendment it was decided to delete the original emergent wetland unit that would have been <br />established along the southeastern side of the reservoir area and northeast of this amendment area. When <br />mining was not to extend this far south that unit made sense, but now that this area will be mined and <br />backfilled that depression that would have been left becomes a liability. In the event there was a heavy flow <br />in the river and major overflow through the Amendment 2 area the depression could provide an opportunity <br />for the river to excavate that area, removing the bank and making the eventual slurry wall structure more <br />vulnerable to erosional damage. In the original plan (Amendment 1) that risk was small at best, but with <br />more openness to the west (upstream) of the depression the possibility of this happening increases <br />considerably. Therefore, rather than leave a depression in that location the depression will be filled to a <br />similar elevation as the surrounding land. This will remove an area of floodwater collection and possible <br />Pueblo East Pit Amendment 2 (2004) Exhibit E Page 2 of 7 <br />