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after stockpile construction and clearly identified with appropriate signs. A berm will be placed around the toe of the stockpile to contain sediment produced from the stockpile. Upon reclamation, the surface elevation in the mined area will be lowered from 20 to 30 feet due to removal of the limestone (except when the limestone layer thickness is minimal, caused by ancient weathering and erosion), assuming approximately a 15 to 20% swell factor for the replaced shale and unconsolidated material. The physical extent of the lowering in surface elevation is controlled by the thickness of the unconsolidated material, shale, and limestone removed, and the actual swell of the excavated and replaced materials. The proposed reclamation sequence and status of each stage of reclamation at the end of the first eight -years of mining activities is illustrated on Figure D -2. Further information pertaining to the final reclamation surface is provided in Exhibit F -1. Exhibit E discusses the reclamation plan. Highwalls at the northern edge and the sides of the pit access road, and along the western side of the Panel will be excavated with slopes not exceeding approximately 70 percent for rock and 30 percent or less for unconsolidated material and shale. Final highwalls will be sloped 4h: 1v and stabilized to control erosion with the use of a geotextile material containing the prescribed seed mix (or equivalent methodology). Dust control measures will follow the dust control plan approved for this operation. Dust suppression at the crusher will be achieved by water spray during dumping, in a mostly enclosed dump hopper, and at conveyor belt transfers to maintain dust within regulated levels. Water for dust suppression on roadways and in the removal of overburden will be applied by water truck, as required. Upon review of all potential impacts to people, structures, water wells, animals and the surrounding natural environment, GCC has found no conditions that would prevent safe operation of the proposed mining and blasting operation at the site. Known domestic and livestock wells are deep, located approximately 450 feet below the Fort Hays Limestone unit in the Dakota Sandstone unit, with steel casing used through the unit to be mined. With the use of time delays and proper stemming of the blast holes, any dust, noise, and ground vibrations will not have long -term effects on the environment. It should be noted that there exists only one dwelling within one mile of proposed blasting and excavating. The geologic unit being mined is the Fort Hays Limestone, which occurs at a very shallow depth in the area to be permitted. Extensive core drilling activities have encountered no significant amounts of water within the surface rock to a depth of 100 feet. CEMENT MANUFACTURING The cement manufacturing facility is permitted for a maximum production capacity of approximately 1.4 million tons per year of portland cement products and incorporates state of the art processing technology. The primary raw material used in the manufacture of portland cement is limestone, which will be quarried on property owned by GCC and leased from the State of Colorado. Quarried limestone is processed through a crusher that reduces this material down to a five -inch size and smaller. After crushing, the limestone is combined with other raw materials such as iron and alumina (an aluminum bearing mineral) and processed through a milling operation. The milling operation grinds the raw materials into a fine powder in preparation for processing these materials through the preheater and kiln system. After milling, the raw materials are processed through a five -stage preheater and calcining vessel. A preheater is designed to heat the raw materials using waste heat from hot combustion gases vented from Technical Rev No. 4 April 26, 2013 D -7