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Principal spillways for each of the ponds w111 consist of CMP risers and <br />conduits which will be equipped with antiseep collars. Emergency spillways <br />will be constricted for each of the ponds. These will be open channel <br />spillways excavated in an abutment or reservoir side. The spillway channels <br />will be riprapped to prevent erosional hazards. <br />The small semi-insitu ponds used to control rvn-off along the coal transport <br />system will not be constructed to the same specifications as the four major <br />sediment ponds. The embankments will typically have sideslopes 2h:ly up and <br />downstream and no cut-off trench will be provided. The spillway system will <br />consist of a v-shaped ditch lined with riprap. The applicant has designed <br />these to retain local runoff for "the required theoretical detention time" <br />(page IV-31~•and part C, "Sedimentation Ponds" section of this TEA). <br />Stream Bed Reconstruction <br />During construction of the surface facilities, Scullion Gulch and three of its <br />tributaries will be relocated beneath the D-Portal area. Restoration of the <br />channels will be accomplished after the D-Portal facilities and sediment pond <br />are reclaimed. The channel will then be returned to its approximate original <br />contour and meander pattern. <br />Other ephemeral and overland flow drainages that might be diverted during <br />construction of surface facilities will be returned to approximate original <br />contour during reclamation, thereby reestablishing the premining erosional <br />balance. (see Maps 43-47 D Portal Area Site Restoration; Map B1~, Refuse Area <br />Sites 1, 2, 3, and 4 Reclamation; Maps 55, 89, 92, 104, and .105). <br />Erosion Control <br />The applicant is proposing a variety of measures to control erosion at the <br />Deserado Mine, thereby reducing the sediment contribution to drainages on and <br />off the permit area. These measures include: protection of topsoil stockpiles <br />during the life of the mine by revegetating with quick-growing species (page <br />V-32c), revegetation and mulching during reclamation, anchoring the mulch with <br />jute netting and contour furrowing on slopes greater than 3h:ly, and loose rock <br />11 <br />