2007-04-05_GENERAL DOCUMENTS - M1977493 (2)

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Climax Mine Arkansas River Restoration Proiect 2.0 DESIGN APPROACH This technical design approach represents the Habitat Team's plan and "vision" for the project, and presents the tasks required to design and build approximately 2,000 feet of new channel for the East Fork of the Arkansas River. Our approach to this restoration initiative reflects the experience of the Habitat Team on similar projects at high altitude in Colorado and throughout the world. 2.1 404 PERMIT COMPLIANCE The U.S. COE Section 404 Permit No. CO-OYT-0211 dated 28 July 1980 authorized Climax to "divert, relocate, and contain approximated 1400 ft. of the East Fork of the Arkansas River in a concrete culvert 7' in diameter". Upon completion of all work in accordance with the permit the active file was closed on 26 June 1985. However, Special Condition "1" of the 404 Permit states: "that upon completion of the mining at Climax the buried section of the East Fork of the Arkansas River shall be restored in accordance with the Climax Mining and Reclamation Plan. The Reclamation Plan shall include but not be limited to resloping of the stream banks, planting, seeding, and fertilization of the vegetation indigenous to the area, re-channelization of the river, and the installation of river improvement structures." As mining activity has been abandoned in this area of the mine, Climax has initiated this restoration project in compliance with Special Condition "1" of the 404 Permit. 2.2 CONCEPTUAL PLAN AND "VISION" The Habitat Team has integrated natural science and engineering principles to produce an innovative design that emphasizes the recovery of aesthetics, geomorphic function and ecologic complexity. Critical elements of our design include: 1) a three-year project schedule, 2) reestablishment of a viable trout fishery, 3) a combination of physical-based analyses and Rosgen's classification methodology to complete field investigations and assist the stream channel design process, 4) retention of the existing pipeline, and 5) transplanting of custom grown and on-site vegetation to the project site. Each of these components is described in greater detail below. 2.2.1 A Three-Year Project Schedule There are several advantages to extending reclamation activities over a three-year period. First and foremost, lengthening reclamation activities over a three-year span will allow for further establishment and development of an effective vegetation cover before reintroducing full flow to the channel. The Habitat Team implemented a pre-design site survey, field evaluation and completion of the design components of the restoration plan in 2006, during the first year of the project. In 2007, the second year of the project, our Team proposes to complete channel construction and habitat establishment, including the application of soil amendments, seeding and transplanting of on-site vegetation to the project area. In 2008, a small portion of the high spring and base flows will be allowed to fill the lake and naturally flow throughout the reestablished channel. Thus, vegetation communities would have at least one complete growing season prior to the restoration of full-flow regimes, which would take place during spring 2009. Empirical studies have highlighted the importance of riparian vegetation in affecting the hydraulic geometry and lateral stability of natural channels. The loss of plants leads to wider channels and shallow flow. Plants interact with and modify the processes of riverbank erosion by altering bank hydrology, flow hydraulics, and bank geotechnical properties. Initial recharging of the reconstructed channel will occur during spring runoff in 2008 when a portion of the flow through the pipeline can be diverted into the new lake and channel. This will ensure that Habitat Team March 28, 2007