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10. Deposit and Underlying Stratum Geology <br /> 10.1 . Mapped Geology <br /> A soil report was generated using the United States Department of Agriculture's Natural <br /> Resources Conservation Services' (NRCS) Web Soil Survey (WSS)2 and is included with this <br /> permit application (Exhibit I Soil Report) along with a site specific soil investigation. <br /> The main applicable United States Geological Survey geologic map for the site is from 2001. <br /> The area of the North Hangs Mine was mapped by Shroba and Scott (2001)3 as consisting of <br /> Holocene and Pliestocene age clast-supported, slightly bouldery, pebble and cobble gravel in a <br /> sand to sandy silt matrix. The North Hangs deposit is underlain by the Eocene to Paleocene <br /> Wasatch Formation, specifically the Eocene aged Shire Member, a nonmarine, predominantly <br /> multicolored fine-grained clastic intervals of thick claystone, mudstone, and siltstone <br /> interbedded with less abundant intervals of minor coarse-grained clastic beds of thin fluvial <br /> sandstone. <br /> 10.2. Geology and Resource Discussion <br /> Details of the Natural Resources Conservation Service (NRCS) site-specific soil report (Exhibit <br /> I) indicate that the deposit is a minimum of 5 feet deep in the area of the deposit. Shroba and <br /> Scott (2001) indicate that gravel deposits along the Colorado River are typically 1-6 meters (-3 <br /> to 18 feet) deep. Material balances for reclamation purposes will be calculated using a topsoil <br /> depth of 18 inches. <br /> Mining will proceed to two feet off of bedrock or a depth of 25 feet; whichever is encountered <br /> first. This depth is based on the operator's experience within the same deposit in Grand River <br /> Park to the east. No bedrock will be exposed by mining. <br /> 11 . Primary and Secondary Commodities <br /> The operation will produce raw materials including sand, gravel, and rock. These materials will <br /> all be processed onsite into construction materials such as rock, sand, fines, and concrete. <br /> Excess overburden will be sold from the site as fill. Excess topsoil may be shipped offsite for <br /> use. Necessary overburden and topsoil will be maintained onsite to retain the backfill needed for <br /> reclamation. Inert material may be imported for backfilling purposes. Any backfill imported for <br /> this purpose will be certified inert with an affidavit signed by the importee. <br /> Western Slope Materials will clearly mark the permit/affected area boundary with stakes <br /> surveyed on site prior to mining. <br /> 2 https://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm. <br /> 3Shroba R.R.and Scott. R.,(2001).Geologic Map of the Silt Quadrangle, Garfield County, Colorado. Denver,CO: <br /> United States Geological Survey. <br /> North Hangs <br /> December 2024 D_6 Lewicki& Associates <br />