2020-12-08_REVISION - M2008078 (23)

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EXHIBIT E Reclamation Plan Lined water storage reservoirs will be the final reclaimed use for the West Farm Pit site. The majority of the mining areas will be reclaimed as a water storage reservoir. The remaining area within the proposed permit boundary will consist of reservoir shoreline, unimproved access roads around the reservoir, and reclaimed or otherwise undisturbed land. Water Storage Reservoir In general, the mining limits will be mined down to the shale bedrock. The reservoir will be separated from the surrounding alluvial aquifer by a slurry wall liner system as detailed in the cross-section shown on the Reclamation Plan Map. The slurry wall liner will be keyed into the bedrock material and extend upward through the entire height of the alluvium. Design specifications and quality control procedures used during the construction of the slurry wall liner will ensure that the reservoir meets the State Engineer's Office (SEO) performance standards for permeability. The slurry wall liner will be constructed concurrently with the mining activities when a new phase is opened for mining. Currently slurry walls have been constructed, tested, and approved around Phases 1 and 2. See the attached liner approval letters from the Colorado Division of Water Resources. All reservoir slopes will be reclaimed to at least 3H:1 V final grade. Final reclamation by capping with topsoil and re-vegetating above the expected reservoir water level will follow mining activities closely to minimize the amount of disturbance at any one time. After final reclamation, inlet and outlet facilities for the reservoir(s) will be designed and installed once the operational criteria of the proposed reservoir have been identified. Reclamation Measures/Materials Handling Topsoiling and seeding will be done to provide stabilized shorelines around the reservoir(s) and to minimize erosion. There will not be known toxic or hazardous materials in the backfill material. Additionally, it is not likely that acid forming or toxic materials will be encountered during mining. The mining will not leave high walls on the property. In addition, there will be no auger holes, excavations, or shafts left on the property. Topsoiling Approximately the top 12 inches of soil on the property is classified as topsoil. This layer includes the root zone of grasses and crops, which will be stripped and stockpiled separately. By using concurrent reclamation techniques, the topsoil is not expected to remain in stockpiles for more than one to five years. If the stockpile remains more than one year, it will be seeded with a fast growing vegetative cover to prevent erosion. Some of the topsoil may be sold as a construction product. Most of the topsoil will be retained on-site to reclaim the reservoir shoreline, and other areas disturbed by mining activities. Where required, topsoil will be replaced to a depth of approximately six inches. RM Prowers Aggregate Operators, LLC. J&T Consulting,Inc. West Farm Pit—M-2008-078 DRMS 112 Permit Amendment Application