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the rotary kiln and calcining vessel. A calcining vessel is designed to further heat the raw materials to the <br />point where calcination of the material is started. Calcination, where limestone is converted to lime, is the <br />first of several material changes that occur within a kiln /calciner system during the manufacture of <br />portland cement. Of the total fuel consumed in a kiln /calciner system, 60 percent is consumed in the <br />calciner vessel. After preheating and calcining, the raw materials are introduced into the kiln. <br />The rotary kiln heats the raw materials to an ultimate temperature of around 2,800 °F. Additional heating <br />of raw materials in the rotary kiln initiates a series of changes that result in the formation of clinker, <br />which is an intermediate product. In physical appearance, the clinker looks roughly like walnut -sized <br />nodules that are dark gray in color. Coal is used as the primary source of fuel for supplying the necessary <br />heat required in the rotary kiln to convert raw materials to clinker. A coal stockpile is maintained in an <br />enclosed covered storage area. GCC is permitted to use tire- derived fuel to supplement coal. Natural gas <br />is used as a startup fuel. <br />Clinker is discharged from the kiln at about 2,200 °F. This material needs to be cooled prior to the next <br />processing step, which is achieved by passing the clinker through equipment known as a clinker cooler. <br />The clinker cooler blows large volumes of air from under the clinker to quickly cool it. This serves two <br />purposes: cooling the clinker in preparation for the next processing step and flash - freezing the desirable <br />chemical and physical properties of this material. <br />The final step in the manufacture of portland cement is the addition of about 5 percent gypsum and up to <br />10% crushed limestone to the clinker. This mixture is then ground to a very fine powder in a process <br />known as finish milling. The product from the finish mill process is portland cement. <br />Most of the portland cement produced at the facility is shipped out by railcar. Some of the annual <br />production is shipped out by truck. The portland cement will be shipped to either distribution terminals or <br />directly to customers. <br />SURFACE WATER MANAGEMENT PLAN <br />Surface water will be managed prior to mining, during mining, and after reclamation using several <br />methods and temporary or permanent facilities. Exhibit D -3 provides an overview of the proposed storm <br />water, management facilities. A description of each facility is provided below and additional design <br />details are provided in Appendix F "Surface Water Management Plan." For the purpose of discussion, <br />these methods are divided into ancillary mining, mining, and reclamation activities. <br />Ancillary Mining Activities <br />Ancillary mining activities requiring surface water management facilities include construction of the <br />access road, railroad spur, borrow area, and plant area. Surface water management facilities have been <br />developed based on the following goals and objectives: <br />• Protect critical transportation facilities. <br />• Protect plant operation from storm water run -on. <br />• Control runoff from disturbed areas. <br />• Manage process water. <br />• Manage domestic wastewater. <br />Protect Critical Transportation Facilities <br />Technical Rev No. 4 <br />April 26, 2013 <br />D -8 <br />