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block. As shown by Exhibit 12-2, a narrow pit will be extended to the south along the Wadge seam cropline from the final pit highwall in the lower block. Given the initial pit configuration, same development material may be moved by scrapers to facilitate partial backfilling of the foal cut in the lower block. The pit will be widened and extended further to the south and west, following the Wadge seam outcrop. A box cut will be opened approximately in the middle of the south extension mining area where the outcrop extends around a natural topographic feature. The resulting pit will connect with the main pit with mining continuing to the south and west to the defined reserve limit. Once the final highwall is established, augering operations will be conducfed and progress to the south, as shown on Exhibit 12-2. All aspecfs of the augering operations are described in Attachment 12-2, Auger Mining. As stated previously in the discussion regarding auger mining in the Lower Block, the auger operation produced unacceptably low recovery rates. SCC will mine the Wadge, Sage Creek, and Wolf Creek seams wherever possible in the South Block. The Sage Creek seam is present in only portions of the South Black. The Wadge and the Wolf Creek seams are the most prevalent and will be the seams concentrated on for dragline mining operations. The mining areas are shown on Exhibit 12.2, Operations Plan. Initially, coal will be hauled from the south block using Haul Road H, which will be extended from existing Haul Road A. As mining proceeds to the south, the haul road network will be extended with construction of additional Haul Roads, I, J, K and L. In order to minimize overall mining-related disturbance, new haul roads will be extended from existing roads with Haul Road I connecting to Haul Road H and Haul Road K connecfing to Haul Road J as shown by Exhibit 12-2. An additional mining area in the South 81ock will allow recovery of the Sage Creek and Wolf Creek coal seams, which are located stratigraphically below the Wadge coal as shown on Exhibit 6-16, Site Specific Geology. The Sage Creek coal is present in only fhe extreme northern and extreme southern portions of the overall area. As mining has progressed south, SCC has gained additional experience in dealing with the ever- increasing steepness of the topography. This affect was not considered in the original timing and sequencing. The addition of the Sage Creek/Wolf Creek mining areas has altered the original sequencing and timing coal removal and reclamation. The Walf Creek mining block began by opening a box cut with initial pre-stripping by scrapers and them completing the box cut with the dragline. The coal removal is a complex operation involving: 1) sufficient room for coal trucks to enter the pit; 2) removing the upper portion of the Wolf Creek seam; 3) removing and disposing of the rock parting; 4) removing the lower portion of the Wolf Creek seam. The short pits in the Sage Creek/WOIf Creek mining block further complicates the coal removal, the dragline needs to complete the entire length of pit prior to coal removal. The reason for having to open an entire pit length before coa! removal cart begin is also due to the extreme grade within the pit. Haul trucks cannot negotiate up the steep pit grade, therefore, they must enter the pit from the upper end and exit from the lower end. PR-06 9 Revised 01/06