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overburden, sliding down from the slopes in either of those areas. This topsoil will be stored for use in final reclamation or immediately distributed over reclaimed areas. The mining methods and engineering techniques in future lifts will remain the same as they were during Phase 1, and the bench mining process will be continued. The surface of the South Pit is completely covered with a sandstone caprock and must be mined, for the most part, from the top elevation down. Therefore, it will be a bench mining process and the benches will be created along the 20 foot contour levels. More than one bench will be created as necessary in wnjunction with the construction of, and/or changes in, the pit roads as required. Not all existing benches will be mined simultaneously, however. Therefore, more than one internal highwall will exist at any given period of time until the entire Section is mined out. When mining of this area has been completed, there will be no working bench remaining, as all of the massive sandstone overburden will have been placed in the bottom of the canyon and in the bottom of Segments H-1 and G-1 in the future Lifts. The massive sandstone and the less massive silts, sands, and shales removed from the main pit, and placed in the backfill, must be balanced to provide the most stable condition possible and maintain the hydrologic balance. The North Pit, after mining, will be at approximate original contour even though the upper layer of materials will have been removed. Backfilling the slope above the sandstone stratum has been previously determined to be insufficiently stable over the long term. The sandstone surface will be fractured by blasting to create a stable base for revegetation. The last pit area will be regraded to conform with the surrounding topography. During Phase II, 8.0 acres are anticipated to be mined annually. The mine plan map indicates the annual progress for the mining areas showing the yearly mining units. The acreages for each mining segment are also shown on the Disturbance Map 5-1, totaling 52 acres. 2.05.3(3) Mine Facilities Mne Support Facilities The Disturbance Map 5-2 shows the location of all of the mine facilities and each structure is labeled according to its intended and current use. All facilities have been designed, constructed, and maintained in accordance with Section 4'.04 of the performance standards. Each facility is designed to be mobile or portable. No permanent facilities will be constructed. All of the mine facilities have been purchased or constructed with the needed mobility in mind. Each structure has been described and the basic designs provided have been • Technical Revision 08 (v 1.3) 5-8 Revised 9!1997