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Rule 6.4.4 EXHIBIT D - Mining Plan <br />Map 5, Mine Plan Map depicts the overall layout of the gravel pit. The plan shows two <br />access points for the pit off of Moffat County Road (MCR) 21. The south access will be <br />constructed first to serve mining operations for phase 1 and part of phase 2. Once these <br />phases are complete, the south access will be removed and the north access will be <br />constructed to serve mining operations for the remainder of phase 2 and phase 3. The <br />scale house, office trailer, storage trailers, and fuel station will be moved from the south <br />access to the north access. Five cross-sections on Map 7 have been prepared to depict the <br />proposed slopes during ` the active mining phase of the project, based upon the <br />recommendations of the geotechnical engineer. <br />(a) The mining operation will start with clearing and grubbing to remove existing <br />vegetation. Any topsoil or overburden soils will be stripped and stockpiled. The <br />initial gravel extracted will be used to construct the access road off of MCR 21. <br />The proposed gravel pit access road will be 40 feet wide and will be adequate for <br />the level of anticipated truck traffic associated with this gravel pit. The sands and <br />gravels will continue to be mined with screening and processing occurring within <br />the pit area. The mine faces will be cut to a 1.5:1 slope. Map 5 Mine Plan Map and <br />Map 7 Mining & Reclamation Cross Sections depict the mine layout and sections <br />during mining operations. The surrounding network of Moffat County Roads will <br />serve as haul routes for the pit products to the surrounding destinations. <br />(b) Earthmoving activities will consist of using backhoes and loaders to remove sands <br />and gravels. The pit-run gravel will either be loaded directly into haul trucks or <br />moved to the crusher. <br />(c) All proposed water diversions and sedimentation ponds are shown on Map 5 Mine <br />Plan Map. A primary stormwater diversion ditch will run just inside the perimeter <br />of the pit area. The secondary stormwater diversion ditch will run east to west <br />through the pit area and connect to the primary stormwater diversion ditch. The <br />stormwater diversion ditch will convey water to a sediment pond. The sediment <br />pond will allow settling of any solids. There will be no outlet for the sediment pond. <br />The captured stormwater will dissipate through infiltration and evaporation. There <br />is one cross culvert under Moffat County Road 21 that discharges into the pit area. <br />This is located approximately 150 feet south of the proposed south access to the pit. <br />A diversion ditch will be constructed to channel this stormwater to the south and <br />into the existing drainageway. This will prevent erosion on the east mine face. The <br />rundown of the diversion ditch into the existing draw will be lined with riprap to <br />prevent erosion. Riprap sizing calculations are attached to this exhibit. <br />(d) The overall maximum area of disturbance proposed is 35 acres at any one time. <br />Approximately 15 acres will be utilized for the access road, processing area, scale <br />station, fueling station, and storage trailers. The remaining 20 acres of the 35 acres <br />will be used for active mining. The approximate dimensions of the active 20 acre <br />mining block will be 800 feet by 1,100 feet. <br />(e) The amount of gravel mined per year will depend on the economy and local <br />demand for these resources. It is not intended for the pit to be an intermittent <br />operation; however, there may be periods of inactivity due to lack of demand for