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box cut that is disturbed twice during the excavation process, and cannot be final graded until <br /> excavation advances away from the box cut area. Surface mining with a dragline progresses in a <br />• logical repetitious sequence: the dragline opens a pit (uncovers/exposes coall, the overburden is placed <br /> in the previous mined pit, the coal is removed, the current highwall is drilled and blasted, the dragline <br /> begins again and uncovers another pit width of coal. This process is repeated until all the coal has <br /> been recovered. This mining process/sequence does not allow more than one pit width to be open at a <br /> time. There may be single pits open in more then one mining area, but physically there can't be more <br /> than one pit width open in a single mining area. However multiple spoil ridges may be present in each <br /> mining area depending on the reclamation Irough grading) sequence. Further discussion of this <br /> situation is presented in Tab 12 and 20. In order to achieve the designed postmining landform, the <br /> necessary backfill material must be available to perform area grading on internal spoil. Generally, <br /> adequate material will not be available until mining has resulted in development of at least two spoil <br /> ridges behind the advancing pit. Tab 20 discusses the area grading concept. When the pit <br /> configuration is regular le.g., typically, interior spoilt, and where sufficient area is available to perform <br /> "area grading", SCC will conduct backfilling and grading activities on areas beyond two spoil rows from <br /> the active pit. Typically, it will take approximately 90 to 120 days to cycle the dragline from one end <br /> of the coal field and back during the permit term; however, due to coal market and operation <br /> considerations, it is periodically required to also cycle the dragline from the south to the north and <br /> back. This could add 60 to 90 days to the dragline cycle before a single spoil row is created. <br /> Therefore, due to the depth of overburden, and configuration and length of the pit, it could take over <br />• one year to generate four spoil rows. This typical cycle has been drastically reduced in the later years <br /> of mining due to the limited areas and required pit orientations due to steep grades. <br /> SCC proposes to utilize the general backfilling and final grading sequence illustrated by Exhibits 19-1 <br /> and 19-tA and the reclamation schedule shown on Table 19-1 to achieve the proposed postmining <br /> topography shown on Exhibits 20-2 and 20-2A. In summary, the annual projection of areas graded are <br /> based upon certain considerations. First, approximately two spoil rows are normally graded <br /> simultaneously, once pit development establishes asteady-state configuration, to achieve the desired <br /> postmining land configuration and to effectively maintain topographic continuity between grading <br /> sequences. The number of spoil ridges associated with irregular box cuts, certain inside or outside <br /> curves, short pits, facility areas, and haulage ramps will not exceed four spoil rows. Second, timing of <br /> grading for specific spoil areas is based upon excavation cycle times and pit configuration. Rough <br /> backfilling and grading will be kept within four spoil ridges and within 180 days, except as discussed in <br /> variance areas requested. Cycle times are dependent upon tactors such as pit configurations, <br /> excavator performance, and customer demand. Third, once grading begins, the number of acres graded <br /> roximately equal to the number of acres disturbed annually. In certain <br />it is a <br />i <br />ll <br />i <br /> pp <br />ven p <br />n a g <br />y <br />annua <br /> circumstances, this generalization may not apply because of spoil material needed to achieve the <br /> designed postmining landform. For example, the backfilling and grading of box pit spoil, final highwalls, <br /> and deep ramps tYPically require the movement of large volumes of spoil for great distances and <br />• requires up to two years after coal removal for final grading. Also, grading of certain box cut spoil <br /> areas (where box cut material is spoiled on recoverable coal) will be temporarily delayed until the <br /> recoverable coal is stripped Isee Exhibit 19-1 and 19-1 A). All of the acres graded in a given year are <br /> projected to be topsoiled and seeded as soon as operationally feasible based on the reclamation <br /> PR04 5 Revised 04/04 <br />