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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. Further discussion of this situation is presented in <br />Tab 12 and 20. In order to achieve the designed postmining landform, the necessary backfill material <br />must be available to perform area grading on internal spoil. Generally, adequate material will not be <br />available until mining has resulted in development of at least two spoil ridges behind the advancing pit. <br />Tab 20 discusses the area grading concept. When the pit configuration is regular le.g., typically, <br />interior spoilt, and where sufficient area is available to perform "area grading", SCC will conduct <br />backfilling and grading activities on areas beyond two spoil rows from the active pit. Typically, it will <br />take approximately 90 to 120 days to cycle the dragline from one end of the coal field and back during <br />the permit term; however, due to coal market and operation considerations, it is periodically required to <br />also cycle the dragline from the south to the north and back. This could add 60 to 90 days to the <br />dragline cycle before a single spoil row is created. Therefore, due to the depth of overburden, and <br />configuration and length of the pit, it could take over one year to generate four spoil rows. <br />Four spoil peaks will also be created by other mining situations. First, in certain locations such as along <br />the ramps and the haul road, in the box cut spoil area, along certain inside or outside curves, along <br />irregular coal recovery areas, areas with short pit lengths and adjacent to facilities areas, it could take <br />more than four spoil rows to create sufficient spoil area to allow final grading to "daylight" and blend <br />into the surrounding topography. Second, in some cases, the box cut spoil material is required to be <br />dozed or hauled forward into the mined area. In this case, the pit progression must move ahead more <br />• than four pit widths and the coal must be removed before the spoil can be excavated and graded to its <br />final configuration. Ramps, roads, or facilities must no longer be required for the mining operation <br />before they can be removed or relocated and the adjacent spoil excavated to final grade. Lastly, the <br />completion of backfilling and grading of final highwalls may require up to two years following coal <br />removal. This is due to the larger operational area required for highwall reduction as opposed to interior <br />spoil grading. <br />Therefore, based on the above reasons, a variance under Rule 4.14.11111c1 is requested for three 131 <br />areas at the Seneca II-W Mine site. These variance areas are depicted on Exhibit 19-1. The first <br />variance area is located in the final 'D' pit area of the northern block. SCC/Peabody Group will be <br />submitting a permit revision to the Division in summer 2001 for the purposes of operating an <br />underground mine off this existing final pit highwall area. Since it is not yet known at this time how <br />much of the 'D' pit area will be required for the underground mine operation, SCC has shown the entire <br />area. Once it is determined how much of the area will be needed, SCC will adjust the size of the <br />variance area and the remaining portion of the 'D' Pit area will be reclaimed. The <br />5 Revised 4/01 <br />