_GENERAL DOCUMENTS - C1981017 (270)

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Pond Outfall Pond Outfall Number Notes Number Notes 001 Old Refuse Pile,East 017 Mine 5 Upper 018 Mine 1 Middle Upper Lower Lower 006 Old Refuse Pile,Top 021 Sutey Refuse Pile 008 Bus Garage Upper East Lower West 022 Mine 2 North Upper 010 Warehouse Lower Upper 023 Mine 3 Bin Pad Lower 024 Slurry Pond 013 Mine 4 025 Rock Tunnel Pad Reclamation construction at each of the ponds was accomplished in the same manner. Construction began by excavating the corrugated metal pipe (CMP) dewatering device located within each pond. During removal of the CMP, the side slopes of each cut were reduced to 2.5 H : 1 V, and the excavation base was widened to five feet minimum width. Following completion of excavation,two courses of rip rap were placed within the cut. The first was mechanically pushed into the base of the excavation, and into the lower portion of the side cuts. The second course was placed over the first. The cut slopes were then severely roughened to minimize erosion potential and to promote successful revegetation. A wetlands seed mixture was distributed around the perimeter of each pond from the water level to an elevation ten feet above the water level. An upland, high altitude reclamation seed mixture was distributed on any disturbed areas above the ten foot elevation. Approximately sixty willow cuttings were planted at the perimeter of each pond. The Best Management Practices employed included severe surface roughening of excavated pond embankments in order to disrupt surface flows and to minimize erosion potential. Construction was accomplished when water levels were low so as to not impact water quality with sediment. Silt fences were erected below excavation areas in order to retain sediment prior to it entering adjacent water resources. All disturbed areas were revegetated with appropriate wetlands and uplands area seed mixtures in order to promote long term stability of the sites. Inspections conducted in 2001 indicate that the Best Management Practices employed during construction were functioning as designed. The rock rip rap placed in the bottom of the excavated spillways was sufficient in size and volume to deter erosion. No erosion of the embankment cut slopes was observed. The severe scarification and the minimal height of these areas were sufficient to minimize erosion potential. The silt fence erected at the base of each cut slope was tightened and stabilized as needed. No erosion or sediment generation problems were noted at any of the discrete pond locations. It is assumed that the vegetative cover will become sufficiently established in 2002 so as to warrant a request for permit termination in 2002 or 2003.