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excavation advances away from the box cut area. Surface mining with a dragline progresses in a logical repetitious sequence: the dragline opens a pit (uncovers/exposes coal), the overburden is placed in the previous mined pit, the coal is removed, the current highwall is drilled and blasted, the dragline begins again and uncovers another pit width of coal. This process is repeated until all the coal has been recovered. This mining process/sequence does not allow more than one pit-width to be open at a time. There may be single pits open in more then one mining area, but physically there can't be more than one pit width open in a single mining area. However multiple spoil ridges may be present in each mining area depending on the reclamation (rough grading) sequence. Further discussion of this situation is presented in Tab 12 and 20. In order to achieve the tlesigned postmining landform, the necessary backfill material must be available to perform area grading on internal spoil. Generally, adequate material will not be available until mining has resulted in development of at least two spoil ridges behind the advancing pit. Tab 20 discusses the area grading concept. When the pit configuration is regular (e.g., typically, interior spoil), and where sufficient area is available to perform "area grading", SCC will conduct backfilling and grading activities on areas beyond two spoil rows from the active pit. Typically, it will take approximately 90 to 120 days to cycle the dragline from one end of the coal field and back during the permit term; however, due to coal market and operation considerations, it is periodically required to also cycle the dragline from the south to the north and back, This could add 60 to 90 days to the dragline cycle before a single spoil row is created. Therefore, due to the depth of overburden, and configuration and length of the pit, it could take over one year to generate four spoil rows. This typical cycle has been drastically reduced in the later years of mining due to the limited areas and required pif orientations due to steep grades. SCC proposes to utilize the general backfilling and final grading sequence illustrated by Exhibit 19-1 and the reclamation schedule shown on Table 19-1 to achieve the proposed postmining topography shown on Exhibit 20-2, Postmining Topography and Drainages. In summary, the annual projection of areas graded are based upon certain considerations. First, approximately two spoil rows are normally graded simultaneously, once pit development establishes asteady-state confguration, to achieve the desired postmining land configuration and to effectively maintain topographic continuity between grading sequences. The number of spoil ridges associated with irregular box cuts, certain inside or outside curves, short pits, facility areas, and haulage ramps will not exceed four spoil rows. Second, timing of grading for specific spoil areas is based upon excavation cycle times and pit configuration. Rough backfilling and grading will be kept within four spoil ridges and within 180 days, except as discussed invariance areas requested. Cycle times are dependent upon factors such as pit configurations, excavator performance, and customer demand. Third, once grading begins, the number of acres graded annually in a given pit is approximately equal to the number of acres disturbed annually. In certain circumstances, this generalization may not apply because of spoil material needed to achieve the designed postmining landform. For example, the backfilling and grading of box pit spoil, final highwalls, and deep ramps typically require the movement of large volumes of spoil for great distances and requires up to two years after coal removal for final grading. Also, grading of certain box cut spoil areas (where box cut material is spoiled on recoverable coal) will be temporarily delayed until the recoverable coal is stripped (see Exhibit 19-1). All of the acres graded in a given year are projected to be topsoiled and seeded as soon as operationally feasible based on the reclamation timetable and site PR-05 5 Revised 01/06