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REQUEST FOR TECHNICAL REVISION Mine ID# M-l993-035 <br /> Mine Name: Swan River Resource Location: Summit County <br /> • promote aquatic macroinvertebrate populations; <br /> • Restore riparian and floodplain function and habitat; <br /> • Improve the aesthetics of the area by creating a naturally functioning ecosystem for public benefit; <br /> • Remove, regrade and cap remaining dredge piles to reduce erosion and promote upland revegetation; <br /> • And demonstrate stream restoration techniques as a model for on-going efforts to reclaim other stream <br /> reaches degraded by historic dredge mining. <br /> Proposed Restoration Reclamation Plan <br /> Similar to the previously completed Reach A restoration, a natural based restoration approach will be taken for <br /> proposed reclamation.The guiding principle of the natural restoration reclamation approach was that the <br /> restored stream system should mimic a natural channel in appearance and function. Recreating the natural form <br /> and function within the stream system will allow lost ecological balance to be restored. Like a natural channel, <br /> restoration has been designed to allow the stream to migrate in response to flow and sediment loads, but <br /> maintain its basic form without significant aggradation or degradation. This approach, rather than a structural <br /> approach to restoration, is of the utmost importance to this project so the restored resources function <br /> holistically with existing resources, and fit with the overall characteristics of the Swan River Valley.The <br /> restoration reclamation plan considered improvements to the channel and the connection between the stream <br /> and adjacent lands, developing an appropriately sized channel to convey typical and bankfull flow events, <br /> promote floodplain interaction and establish native riparian and upland vegetation communities. <br /> The proposed channel profile is designed to replicate a natural riffle-bend-pool system. Riffle-bend-pool systems <br /> are characterized by faster moving riffle sections leading to long pool sections around the apex of stream <br /> meanders. Stream restoration proposed in this restoration reclamation plan includes re-meandering a portion of <br /> the Swan River that has been channelized. The channel has been designed to mimic pre-disturbance conditions <br /> that may have existed within the permit boundary. The restored stream is intended to act as a natural channel <br /> and, like a natural channel, some amount of lateral migration is expected over time. <br /> Geomorphologic values, standard principles and observations of regional healthy stream characteristics were <br /> used as the basis for the desired channel shape,widths and depths. Native vegetation communities will be <br /> established based on locally appropriate reference standard conditions. <br /> Channel Form <br /> A key element of the proposed channel design is creating a meandering pattern that is in balance with the <br /> natural hydrograph.These types of stream systems naturally are dominated by repeating riffle-bend-pool <br /> complexes and point bars. Riffles are the steeper sections of the stream and generally located upstream from <br /> larger channel bends. Riffles are characterized by larger substrate material and swift flows. Pools are located <br /> downstream of riffles and are typically at or near the more pronounced bends in the stream. The higher flow <br /> velocity of the riffle sections provide energy required to continually scour the pools, maintaining quality pool <br /> habitat. Glides are located between pools and riffles and generally have a mild adverse slope leading from the <br /> end of a pool up to the start of the next riffle. Glides have a well-defined thalweg that contain flow to a defined <br /> channel during low flow periods. <br /> The natural channel form for this section of the Swan River would be characteristic of a Rosgen C Stream Type. <br /> 3 of 7 <br />