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<br /> <br /> <br />2-1 <br /> <br />Section 2 <br />Site Description <br />2.1 Site Location and Access <br />The mining operation will develop limestone reserves from the Fort Hays and related formations in <br />portions of U.S. Geological Survey (USGS) Sections 24 and 25, T20S, R68W in Freemont County and <br />Section 19, 20, 29 and 30, T20S, R67W in Pueblo County (Figure 1). <br />The RCQ property is accessed from Florence by traveling south on State Highway 67 for <br />approximately 11 miles and turning east (i.e., left) onto State Highway 96 to travel to two separate <br />property access points along Highway 96. To access the north end of the RCQ study area, travel <br />approximately 6.5 miles to the access gate. To access the south end of the site, continue along <br />Highway 96 approximately 3 miles to the Holcim access gate (Figure 1). <br />2.2 Hydrologic Setting <br />The RCQ property is located within the Upper Arkansas River subbasin, a USGS fourth level <br />hydrologic unit code (HUC) subbasin (HUC 11020002) that drains into the Arkansas River basin. The <br />aquatic resources within the RCQ study area include several ephemeral tributaries to Red Creek and <br />the Arkansas River, an intermittent section of Red Creek, and a perennial section of Red Creek <br />(Figure 2). Observed surface waters supported the delineation wetlands downstream of field recon <br />location 004 and upstream of location 011; surface water within Red Creek was not observed <br />upstream of recon location 004 and downstream of location 011. <br />2.3 Geology and Hydrogeology <br />The RCQ property is comprised of Cretaceous age marine sediments of inter-bedded limestones and <br />sandstones including the Fort Hays Limestone and the more argillaceous Smoky Hill <br />Limestone/Shale Members of the Niobrara Formation. Underlying the limestone units is the Codell <br />Sandstone Member and Blue Hill Shale Member of the Carlisle Formation. The primary geologic <br />strata at the site are illustrated in Figure 3. <br />The Smoky Hill Limestone/Shale overlies the Fort Hays Limestone and consists of up to 125 feet (ft) <br />of dark grey, thin-bedded limestone. The Fort Hays Limestone is the primary limestone resource due <br />its high lime content and consists of approximately 35 ft of medium to light-grey, distinctly bedded <br />limestone with numerous thin clay interbeds. The Codell Sandstone consists of approximately 20 to <br />30 ft of light grey, fine-grained, massive sandstone. Contact between the Codell Sandstone and the <br />overlying Fort Hays Limestone is denoted by 2 to 3 ft thick transitional zone of dense, arenaceous <br />limestone. <br />The geology of the RCQ property likely exerts a strong influence on local groundwater conditions. <br />Groundwater was not observed in the limestone units during installation of monitoring wells in <br />November 2021, with the exception of groundwater encountered in Well 2N within a highly <br />fractures/faulted zone at approximately 35 ft below ground surface (bgs). Groundwater levels <br />present in the Codell Sandstone are shown on Figure 4. The contact of between the limestone and <br />sandstone was encountered at shallower depths on the north side of Red Creek in Wells 1 and 2S <br />than in Wells 3 and 4. Wells 3 and 4 encountered the Codell sandstone at greater depths resulting <br />in the groundwater table above the contact.