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• <br />0 <br />5.0 EX MIT D- MINING PLAN <br />5.1 General <br />The proposed Morton Lakes Sand and Gravel pit is anticipated to affect <br />approximately 132 acres of land located on either side of Big Dry Creek. <br />The aggregate deposit consists of alluvial sand and gravel overlain by topsoil and <br />overburden. The topsoil layer and overburden layer will range from three to five feet in <br />thickness, while the sand and gravel deposit is 25 to 30 feet thick. The deposit is <br />underlain by bedrock shale. The maximum depth of excavation will be approximately 35 <br />feet. <br />The alluvial groundwater levels are approximately 3 to 5 feet below natural ground <br />level. The deposit is therefore classified as a wet alluvial deposit. However, the sand and <br />gravel deposit will be mined dry once the each mining stage has been de-watered. The <br />sand and gravel deposit is cataloged in the report Sand, Gravel and Quarry Resources, <br />Colorado Front Range Counties (Colorado Geologic Survey, 1974). <br />An estimate of overburden and resource volumes for the property is as follows: <br />Mining Stages Acres Sand and Gravel Overburden <br />Stage 1 17.0 1,000,000 tons 85,000 yds <br />Stage 2 21.6 1,300,000 tons 105,000 yds <br />Stage 3 36.4 2,200,000 tons 175,000 yds <br />Stage 4 37.3 2,240,000 tons 200,000 yds <br />Stage 5 19.3 960,000 tons 92,000 yds <br /> <br />5.2 Mining Method <br />Dry mining techniques will be used. Initially, a dewatering ditch will be excavated <br />around the perimeter of each mining stage and groundwater recovered in the dewatering <br />ditch will be discharged to the South Platte in accordance with Colorado/NPDES <br />discharge permit regulations. <br />1