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<br /> <br />t <br />t <br /> <br />1 <br />1 <br /> <br /> <br />1 <br /> <br />1 <br /> <br />1 <br /> <br /> <br /> <br /> <br /> <br /> <br />BEST MANAGEMENT PRACTICES OVERVIEW <br />Maintaining or establishing surface hydrologic stability is a critical component in the mining <br />and reclamation process. Adequately controlling erosion and minimizing sediment <br />transport serves to prevent or minimi~r. uttpacts t0 receiving waters, and supports and <br />enhances the long-term stability of reclaimed areas. There are a variety BMPs that ma be <br />employed to accomplish these goals during development, operation and reclamation of the <br />project. BMPs may be used independently or in combination to accomplish erosion and <br />sediment control objectives. While serving a common purpose there are distinct <br />applications to which BMPs are best suited. <br />Erosion and sediment control requires the use of specific BMPs that address different <br />physical conditions than those associated with channel reconstruction. Generally, surface <br />sheet flow control practices vary physically from those used to control concentrated surface <br />flows because of the differences in environmental conditions and requirements. Selecting a <br />single or combination of BMPs for use on a site must take into consideration the variety of <br />flow conditions that may occur there. Often then; isn't a correct solution, but rather a <br />variety of combinations that may accomplish erosion and sediment control objectives for a <br />given location. Typically, complex flows require more sophisticated structttres and <br />practices than less complex flows. <br />BMPs have been grouped in these appendices based on their primary uses or applications. <br />While the use of some of them may be limited to the category in which they are placed, <br />many of them present useful applications in multiple categories. Typical installations for <br />BMPs are provided for clarity. The practice of routinely prescribing controls for erosion <br />and sedimentation problems will be avoided. Each drainage situation will be treated <br />creatively to min;mi~e construction and treatment costs, while striving to maximi~P the <br />effectiveness of BMPs. <br />BIOTECIiNICAL STABILIZATION MEASURES <br />When reconstructing channels it may be possible to incorporate biotechnical stabilization <br />measures to provide for erosion stability. Biotechnical stabilization measures involve the <br />use of selective vegetation plantings to protect the channel from erosion and to maintain <br />alignment and grade. Herbaceous rhizomatous species are normally used through out the <br />channel profile. Woody species may be planted in the secondary floodplain to control <br />channel cross-sectional profiles and gradient. <br />It may be necessary to provide suitable substrates th the pilot channel so that the stream <br />channel is capable of naturally self armoring. Methodologies for evaluating a channel's <br />ability to self armor based on particle size are available. When excessive channel erosion <br />occurs these methodologies may be used to evaluate self-armoring capabilities. Based on <br />such analyses, additional larger substrate particles may be added to a streambed to promote <br />self-armoring. <br />Various biotechnical engineering methods and practices that may be used to accomplish <br />erosion and sediment control in reconstructed channels include live cuttings, fascines <br />(wattles), brush layering, vegetated dikes, live cribwalls and tree revetments. These <br />techniques may be used individually or in combination depending upon site needs and <br />requirements. Site specific plans using biotechnical stabilization measures will be prepared <br />as appropriate sites are encountered during project development. <br />E-1 <br />