2011-11-04_GENERAL DOCUMENTS - C1981019

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control structures that will aide in reducing the amount of sediment ultimately reporting to Prospect Pond via reclaimed (3+ years) or newly reclaimed (0 -3 years) watershed locations. This stock pond will also facilitate post- mining land use targets by serving as crucial watering location for livestock and wildlife. In addition to construction of a sediment stock pond, approximately 975 feet of rock ditch was constructed requiring roughly 1775 cubic yards of rock to be hauled into this reclamation area. Methods utilized in the construction of the ditches in the West Pit, mentioned above, were also used in to construct the rock ditch in the East Pit. 2011 also marked the first season of reclamation efforts in the recently established South Taylor Pit. The 49 acres of regrade efforts was completed entirely by dozer pushes. In addition to regrade work, approximately 975 feet of rock ditch was constructed requiring nearly 1450 cubic yards of rock to be hauled into this reclaim area. Methods utilized in the construction of the ditches in the West Pit and East Pit, mentioned above, were also employed to construct the rock ditch in the South Taylor regrade area. The most innovative measure of the reclamation completed in the South Taylor area was the construction of an Aspen and Tall Shrub field trial area. In a cooperative working agreement with the Colorado Division of Reclamation Mining and Safety (CDRMS), and the Colorado Department of Wildlife (CDOW), Colowyo implemented three one acre plots for Tall Shrub and Aspen trial area. The area was first regraded to the approved Post - Mining Topography and three acres were identified for the trial area which included deep and thin topsoil locations. The deep topsoil area was constructed on two of the three acres which required a forty eight inch deep topsoil replacement depth. Both of these two acres were seeded with a tall shrub mix and a Grassland mix to minimize erosion. The thin topsoil area had a four inch topsoil replacement depth and seeded with a tall shrub seed mix. Colowyo then planted 1650 containerized shrubs over the entire trial area which included Serviceberry, True Mountain Mahanoy, Serviceberry, Chokecherry, and Aspens respectively. The entire trial area was also enclosed with "elk proof' exclusionary fence to protect the trial area from ungulates depredation. Perhaps Colowyo's most impressive and important reclamation tasks during the 2011 reclamation season dealt with continued efforts implementing a variable topsoil replacement program and identification of areas for specific seed mixes and post- mining land uses within each reclaimed area. Through the end of 2009 and most of 2010, Colowyo worked closely with members of the CDRMS and CDOW to create and implement a ground- breaking Variable Topsoil Replacement Depth program for all remaining topsoil replacement activities at the mine site. In short, this topsoil replacement program was designed to mimic the natural depths of topsoil one would find in a typical drainage, thus providing more suitable and specialized environments for woody species reestablishment. Rather than a uniform depth of topsoil over an entire reclaim location, as is the most common practice, Colowyo created some sites with extremely shallow topsoil (ridge tops and topographically flat locations) designed at reducing grass stand establishment and their resulting competition with shrubs for water and soil nutrients. Colowyo also created additional sites (steep slopes and bottoms of drainages) with extremely deep topsoil depths. These sites will ideally benefit woody species like aspen and chokecherry. This non - uniform redistribution of topsoil will theoretically encourage plant diversity and ultimately produce microclimates such as those found in nearby native land.