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� ( IV D <br /> EXHIBIT D 022 oN MINING PLAN <br /> ;,�V1MW1N�AN <br /> 1 . General Mining Plan <br /> The property boundary has been surveyed on site and the permit area will be surveyed prior to <br /> any additional acreage to the site disturbance. Map C-2 shows the mining plan. Mine access will <br /> remain the same from Colorado State Highway 65 directly west of the site. Mining of the Delta <br /> Paving Gravel Pit will involve roughly 110 acres of total disturbance. The primary commodity to <br /> be mined is sand and gravel for use in construction materials such as crushed rock, sand, <br /> washed rock, concrete, and asphalt. Fill dirt may be incidentally produced during the operation. <br /> The sand and gravel deposit averages 15 feet in thickness within the alluvial deposit. It is <br /> overlain by approximately 5 inches of topsoil and 3 feet of overburden. All mining will be to the <br /> bottom of the gravel deposit with 2H:1 V slopes on the perimeter. Highwall mining with a near <br /> vertical slope will progress to the halfway point of the final mining slope. This allows for the <br /> remaining highwall material to be knocked down to the final mining slope with a dozer after <br /> mining is complete in an area. However, the slopes adjacent to the previously reclaimed <br /> groundwater lake in the west of the phase 1 pit will be mined to a 3H:1 V slope. Refer to Map C- <br /> 3 for cross sections that demonstrate the full mining and final reclamation slopes. <br /> Mining will be completed in four phases corresponding with each pit. Mining and reclamation will <br /> be done concurrently as mining progresses to minimize the total disturbance. There is sufficient <br /> topsoil and overburden on site to successfully reclaim the site to its final condition as <br /> groundwater lakes and rangeland. Reclamation will include regrading of the site, topsoiling, and <br /> revegetation. <br /> Dozers and scrapers will be used to strip topsoil and overburden from the areas to be mined to <br /> be stored in the designated stockpiles. Any stockpile to be in place longer than 90 days will be <br /> seeded to prevent erosion. Sand and gravel will be extracted using loaders, excavators, dozers, <br /> and trucks. Excavated material will be hauled to the center of the site for processing. Processing <br /> of material will include screening, washing, crushing, and the production of concrete and <br /> asphalt. <br /> The pits will require dewatering as groundwater is located approximately five feet below the <br /> surface. The active mining pit will be dewatered using pumps. Groundwater from the pit will be <br /> pumped directly to the reclaimed pond in the center of the property serving as a sediment <br /> settling pond. Any excess water from the pond will then be released to the Relief ditch to return <br /> to the Gunnison River on an as needed basis. Discharge from the settling pond will be limited as <br /> the presence of excess water is not common and typically only occurs during storm events. An <br /> NPDES discharge permit is already in place for these potential discharges of stormwater or <br /> process water. Any groundwater exposed from mining will have associated gravel well permits <br /> and appropriate augmentation plans as needed. <br /> Delta Paving Gravel Pit D-1 Lewicki&Associates <br /> September 2022 <br />