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<br /> <br />Bear Creek Quarry (M-1977-344) Permit Amendment <br />Holcim US Inc, 3500 Highway 120, Florence, CO 81226 <br />Phone (719) 288-1443 www.holcim.us 47 <br />Plant growth material will be salvaged and stockpiled during all site development and mining activities. Up <br />to two feet of plant growth material will be ripped and pushed into a temporary stockpile. Haul trucks will <br />transport the material to the property boundary and planned quarry area for construction of a 10-foot-high <br />perimeter berm. In the event plant growth material will not be used in reclamation within one year, it wil l be <br />seeded with a temporary seed mix to stabilize the surface until the material is needed in final reclamation. <br />During initial mine development, a temporary stockpile will be located in the northwest corner of Section <br />24 (Figure 2.4.5-1). The temporary stockpile will be 1,200 feet by 800 feet with a total capacity of 3.1M <br />tons. It will be constructed in two lifts. The bottom lift will be plant growth material salvaged from <br />infrastructure and initial mine development. The top lift will be overburden and limestone as needed as the <br />mining operation commences. Once sufficient mine floor is mined out, the top lift will be pushed into the <br />quarry as backfill for slopes. The stockpiled topsoil will be placed in the perimeter berm. The anticipated <br />life of the temporary stockpile is less than 20 years. <br />The limestone mine will develop as a surface mine with benches and a perimeter berm (Figure 2.4.5 -2). <br />Limestone will be mined by cutting benches with a vertical face of 36 feet and a bench of 20 feet. The <br />depth of limestone is approximately 140 feet deep with Codell sandstone below the limestone deposit. The <br />crest of the mine bench will be 150 to 200 feet within the permit boundary. A 10-foot berm will be <br />constructed of overburden approximately 100 feet from the crest of the limestone bench. <br />The sandstone mine will be an open pit mine in the floor of the limestone mine. After extracting the <br />limestone, a sandstone pit will be developed in the Codell. Sandstone will be mined from two 23-acre <br />locations along the west boundary; one in each Section. Sandstone will be mined to a depth of 15 feet as <br />a typical open pit mine using backhoes and haul trucks. The slopes of the sandstone pit will be 3H:1V. <br /> <br />Figure 2.4.5-2 Limestone bench mining cross section <br />Daily mining activity will be performed by diesel fueled loaders, a dozer, motor grader, three 100 -ton off- <br />road haul trucks, a 20,000-gallon water truck, and electric backhoes. Once the plant growth material is <br />salvaged and the mine area is leveled, the mine area will be drilled in preparation for blasting at depths <br />based on the geologic stratigraphy of overburden, translime, Fort Hays limestone and Codell sandstone. <br />The drilling patterns are described in the Blasting Plan (Appendix 4.1). The blasted material is segregate <br />as overburden and limestone. Overburden is hauled to the waste dump area and stockpiled for use during <br />final reclamation to rebuild slopes and bring up the elevation of the mine floor or it will be used to construct <br />the perimeter berm. <br />Limestone is processed twice in the RCQ, prior to being conveyed to the BCQ. Electric backhoes will feed <br />one of two electric primary jaw crushers (each rated at 650 tons per hour [tph]) located near the working <br />face. The crushed limestone will be conveyed to the electric secondary cone or impact crusher (rated at