2019-10-08_PERMIT FILE - M2019054 (74)

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Exhibit E Skull Creek Sand Project Project Area Description The Skull Creek Sand Project is located approximately 2.7 miles NW of Massadona, CO on State Lands. The Project Boundary encompasses approximately 476.4 acres of which there will be approximately 140 acres of disturbance due to mining activities. Elevations of the Project Boundary vary from 5,665 ft to 6,040 ft. All affected lands within the project boundary will be reclaimed and revegetated as described below. The final design topography of the project area is shown on Map E-1, while Map E-2 shows the approximate extents and sequence of reclamation activities on Affected Lands. The reclamation plan includes methods and descriptions of measures that will be taken to ensure that affected lands will achieve: • Complete Backfill and Final Grading • Proper placement of soils • Adequate fertilization and mulching of growth media • Sufficient seeding of desired species • Targeted revegetation of native plants Reclamation Plan Phase 1 - Earthmoving, Backfill and Regrading As described in Exhibit D, regrading of the open pits is integrated into the mining sequence by utilizing the pits for concurrent backfill. As the pits are mined from East to West, spoil material from the mining face and product rejects from the Spoil & Product Rejects Stockpile (SPRS) or directly from the sand processing facility will be placed in backfill by the mining fleet by either truck and shovel haulage or by direct push with a bulldozer. The backfill will be placed and regraded to achieve the final landform depicted in Map E-1. The final landform has been designed with slopes having a ratio no greater than 3:1 and generally averaging between 5:1 and 10:1. The final backfill landform has been designed to conform with regional topography, to adequately store all spoils and product rejects, and to properly re-establish pre-mining drainage patterns. To conform with regional topography, the landform is purposefully irregular, grading out flat benches and terraced waste dumps to establish a gently sloping topographic ridge. To adequately store all spoils and rejects, the final landform accounts for 33% swell of the interbedded shale and sandstone overburden. It also accounts for void loss of the sandstone product and a 20% return of the sandstone product rejects from the processing facility. These rejects are expected to swell at 60%from in situ volume. Overall, the final landform allows for a volumetric percent difference of approximately 15% from the pre-existing state. By establishing gentle slopes and a topographic ridge along the spine of the backfill, the final landform minimizes the possibility of post-mining erosion and routes surface drainage to their pre-mining conditions. 7 10/3/19