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M1 Anne Baldrige - 2 - February 19, 1985 Rule 2.06.5 - Variance from Approximate Original Contour Requirements The applicant has amended the original application, in order to achieve approximate original contour. Therefore, response to this section is not required. Rule 4.14 - Backfilling and Grading The amended reclamation plan requests approval for delay in contemporaneous reclamation, as allowed under Rule 4.14.1(1)(c). This request is necessitated by the amended mine plan. The plan was amended to eliminate the need for deposition of box cut spoil outside the mined area. This desirable amendment resulted in the rehandling of the box cut spoil, which will remain unreclaimed from 1985 though 1987. The applicant does not propose to temporarily reclaim this area, because the vegetation would have an insufficient growing season prior to permanent reclamation. The second area for which the applicant requests variance from the normal contemporaneity requirements is northwest of the box cut location, near the end of the 1986 mined area (see Map 12-1). The drag line will return to the box cut location. This will leave approximately 3,200 feet of open pit, and at least several rows of spoil piles. This area cannot be permanently reclaimed until mining recommences in 1991 and progresses further toward the northwest. A similar situation in encountered near the southeast terminus of the mined area in 1990. Approximately 3,400 feet of pit will be left open at that location for two years. Geotechnically, I see no problem with these requested contempraneity variances. However, I have not considered the environmental impacts of delayed reclamation, such as possible water quality or wind erosion effects. The applicant completed projections of overburden bulking, in order to project post-mining topography within the mined area. The projections included within the original application were completed prior to submittal of the original application in 1982. Subsequently, in connection with operations at the existing Seneca II mine, the applicant has completed observations of reclaimed land. These aerophotogrammetric observations have determined that the actual bulking factor slightly exceeded the original projection (19.8% in the operator's terminology, versus 15.3% projection). The Division reformatted the applicant's analytical projections in a format more familiar to the Division. The applicant projects an average overburden swell factor (loose swollen overburden volume divided by bank overburden volume) of 1.32. Further, the applicant projects a bulking factor (swollen backfilled volume divided by excavated pit volume) of 0.91. This suggests an average post-mining topographic deflation of 4.6 feet. Adjusted for the possible discrepancy in observed versus original projected bulking, discussed