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in the direction of the mining cat/ face. This extension 11'111 be through the mid- section of the panel. The in crusher and mobile conveyors may he moved several tulles a year to stay lrltll the mining face. block will be closed and reclaimed, and the sump, equipment access ramp, and conveyor will be moved to a new pit entry point south cast of the initial —i g arm Because of the gradually decreasing thickness of the limestone in an up- gradient direction, the area disturbed for each year of mining will vary, gradually increasing upslope. In addition, the area mined each year will depend on the demand, for Portland cement and any slight variations in the limestone. Figure D -1 illustrates the area disturbed for each of the first 8 years of mining. . -, , - I I. A box cut of about 16 acres (1,400 feet long by 150 feet wide) with an average d initiate the operation and be connected to the adjacent plant by an excavated earth incline truck and access Material above the limestone from the initial cut has been stored in an area south and south -east of mining year blocks 4 and 5, as noted on Exhibit D -1, and has been temporarily revegetated for stabilization. (Pre- stripped materials from the Year 6 operating block (not illustrated) will be stored above the Year 15 mining block.) excavated with slopes not exceeding 70 percent. Final highwalls will be sloped 4H:IV and stabilized to control erosion. See the Surface Water Management Plan (Appendix F) for a discussion of storm water controls. TR 4 with Markup April 26, 2013 Mining of the limestone and up to 5 feet of bottom sandstone will continue from the initial box cut in a southwesterly direction as shown on Exhibit D -1. Incremental production panels will be established generally along strike. The panels are offset slightly relative to strike to achieve an overall slope along the pit floor in order to facilitate passive drainage to the sump (settling pond) located in the first year mining block. The dimension of weekly panels must be at least 24 -feet wide by 600 -feet long. There are, regardless of the thickness of the limestone layers, approximately 7,000 to 15,000 cubic yards of limestone to be removed in the weekly panels. The limestone to be removed is covered by an unconsolidated layer (including subsoil and topsoil) and shale approximately 0- to 45 -feet thick in the area to be mined. The average yearly panel dimension for the first five years of mining will be approximately 450- to 600 -feet wide (upslope) by an average of 1,400 -feet long by 20 to 30 feet in thickness of limestone (plus 1 to 6 feet of the Codell Sandstone)to maintain a proposed limestone production level of 2.25 million tons per year. The total area affected by mining in any one given year will be dependant on the thickness of limestone removed in order to maintain the annual production target. Areas undergoing active quarrying subject to wind erosion will be limited to 40 acres at any point in time. As each production block progresses, unconsolidated material and shale, along with topsoil and subsoil will be removed from the pre -strip areas and carried behind current production panels and placed on the pit floor from which the limestone and sandstone have has been removed, or upon areas at which regraded unconsolidated materials and shale have been placed. This backfill material will be graded prior to subsoil and topsoil placement and seeding, sequenced according to weather conditions and seasonal revegetation periods. The combined area of active mining, processing, stockpiling, and reclamation will vary from year to year based on thickness of the various materials encountered and production requirements. D -3