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Earth Moving <br /> Areas to be mined are prepared by removal of topsoil and overburden. Each preparation area <br /> may be 100 feet or more in front of the mining operation. Where it is found, surface topsoil <br /> material will be stripped separate from the underlying, deeper subsoil or overburden material. <br /> This topsoil layer contains most of the soils organic matter and will be stockpiled separately for <br /> use in reclamation. Once the surface layer has been removed, the rest of the overburden will be <br /> stripped and stockpiled separate from the surface layer. Due to the short time frame of the <br /> mining operation, it is anticipated that stockpiles will not remain through a growing season. <br /> Therefore, the stockpiles will not be seeded for stabilization. <br /> During mining and prior to reclamation, the mining face and walls will be a nearly vertical to <br /> '/2H:IV slope (see Exhibit E, Mining Plan Map). Generally, mining will progress down to the <br /> depth of quality aggregate material or about 10 feet below the surface. Mining in Phase 1 and <br /> Phase 2 may occur to 10 feet below the ground surface in the northern part of the mining cells, <br /> but as mining progresses south the depth of mining will decrease to zero so that the final mine <br /> cell will free drain from north to the south. Mining may also be shallower near the south side of <br /> Phase III. However, regardless of mining depths, backfill and grading will be used to allow the <br /> mine cell to free drain from north to south. <br /> As the mining face progresses, pit sidewalls behind the mining activities will be reclaimed. So <br /> that reclamation activities do not interfere with mining operations, pit sidewalls may extend <br /> 300 feet behind the active mining face without being reclaimed. The aggregate material will be <br /> recovered using equipment typical for sand and gravel mining operations. Earth moving <br /> equipment may include, but are not limited to dozers, loaders, scrapers, and excavators. The <br /> aggregate material from the pit will be temporarily stockpiled within the pit or transported <br /> directly for processing or off the site. During mining and reclamation activities, watering trucks <br /> for dust control will be used as needed. <br /> In general, setbacks from the mine pit top of slope to the proposed permit boundary will be <br /> 20 feet or greater. The exception to this setback is along the northern side of Phase I and <br /> Phase II where mining will extend to the permit boundary in order to create a smooth transition <br /> with reclamation at the adjacent Harmony Gardens Site (M-2017-021). Mining setbacks from <br /> the Sinclair gas pipeline easement, City of Greeley water line easements, and Lake Canal Ditch <br /> will be 50 feet or greater and structure agreements will be offered to each of the structure <br /> owners. <br /> Topsoil and overburden material excavated from the pit will be stockpiled and used for <br /> backfilling mine pit slopes and other reclamation activities. The non-marketable material <br /> stockpiles will be created adjacent to the areas that will be backfilled or on the pit floor. When <br /> sufficient material is available in the stockpile, the material will be backfilled into previously <br /> mined areas. <br /> The side slopes of the mine pit will be backfilled, graded to a minimum 3H:1 V slope, and seeded <br /> as mining progresses. Approximately 3,960 feet of pit side slopes will be created during mining. <br /> Since reclamation is anticipated to be concurrent with mining operations, the actual length of <br /> side slope requiring backfilling and grading at any point in time is expected to be far less than <br /> 3,960 feet. The deepest areas of the mining cells are anticipated to be near 10 feet high. Once <br /> Harmony Windsor Site <br /> DRMS Limited Impact 110 Permit Application Page 8 <br />