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EXHIBIT D MINING PLAN <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. The mine will <br /> include 116 acres of disturbance. The primary commodity to be mined will be sand and gravel <br /> for use in construction materials. These construction materials may include crushed rock, sand, <br /> washed rock, concrete, and asphalt. Fill dirt may incidentally be produced as well. The mine will <br /> be accessed from the existing connection to US-85. This access road will require improvements <br /> to be able to support mine traffic. All earthwork required to improve the road will be completed <br /> prior to mining. Slurry walls will be installed surrounding Pod 1 and 2, and another surrounding <br /> Pod 3. These walls will stop groundwater from infiltrating into the pits, and facilitate water <br /> storage in the reclaimed pits. Slurry wall construction will be completed prior to mining in any <br /> given pod. <br /> The sand and gravel deposit is an average 25 to 45-foot thickness within the alluvial deposit <br /> surrounding the South Platte. The deposit is overlain by an average of two feet of topsoil and <br /> two feet of overburden. It is split into two terraces: a lower terrace adjacent to the Platte River <br /> and an upper terrace along US-85. The lower terrace is made up of the primary sand and gravel <br /> layer overlain with topsoil and overburden. An additional sand layer overlies the gravel deposit, <br /> starting midway through the lower terrace and increasing in depth to the southeast. It reaches <br /> an average thickness of 28 feet in the easternmost mining area, Pod 3, on the upper terrace. <br /> The bedrock is an olive-gray claystone and siltstone that exists approximately 30 to 40 feet <br /> below the surface. <br /> Mining will occur in three separate pods, starting on the lower terrace and proceeding east: Pod <br /> 1, Pod 2, then Pod 3. The processing area in the northern part of Pod 3 will be mined last. <br /> Mining and reclamation will occur concurrently as mining progresses in order to minimize the <br /> total disturbance. There is sufficient topsoil and overburden on site to successfully reclaim the <br /> site to its final condition as water storage ponds surrounded by rangeland. Reclamation will <br /> include backfilling and regrading of the site, topsoiling, and revegetation. The slurry walls <br /> installed prior to mining will be retained. <br /> All mining will continue to the bottom of the gravel deposit with 1.51-1:1 V final mining slopes <br /> along the perimeter. The active highwall will be at a near vertical slope, and will progress to the <br /> halfway point of the final mining slope. This allows for the remaining highwall to be knocked <br /> down via dozer to create the completed mining slope. Slopes will then be backfilled with sand or <br /> overburden to the reclaimed 3H:1V slopes. Refer to the cross sections on Map C-3 for the <br /> various slope details throughout mining. <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 /> Ewing Gravel Pit <br /> August 2023 D'1 Lewicki&Associates <br />