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The application states that the mining plan for the Seneca II-W Mine was developed in <br />conjunction with the Seneca II Mining Plan. The pit progression design was based on <br />standard mining practices, tried and proven at the analogous Seneca II Mine. The <br />backfilling and grading plan is found within Volume 13, Tab 20. The reclamation <br />schedule, including a request for a variance from the contemporaneous reclamation <br />requirements of Rule 4.14 is contained within Volume 12, Tab 19. <br />The applicant completed projections of overburden bulking, in order to project <br />post-mining topography within the mined area. The projections included within the <br />original application were completed prior to submittal in 1982. Subsequently, in <br />connection with operations at the existing Seneca II Mine, the applicant has completed <br />topographic observations of reclaimed land. These aerial observations have determined <br />that the actual bulking factor slightly exceeded the original projection (19.8% in the <br />operator's terminology, versus 15.3% projection). <br />In completing its review of the amended application, the Division converted the <br />applicant's analytical projections into an analytical format more familiar to the Division. <br />The applicant projects an average overburden swell factor (loose swollen overburden <br />volume divided by bank overburden volume) of 1.32. <br />Further, the applicant projects a bulking factor (swollen backfilled volume divided by <br />excavated pit volume) of 0.91. Considering the average mined depth and extracted seam <br />thickness, this suggests an average post-mining topographic deflation of 4.6 feet. <br />Adjusted for the possible 4.5 percent discrepancy in observed versus original projected <br />bulking discussed above, the post-mining topography might rise by an additional 1.8 <br />feet, resulting in an average post-mining topographic deflation of 2.8 feet. In either <br />case, the projected post-mining topographic configuration is considered by the Division <br />to constitute an acceptable approximate original contour configuration. <br />In the first permit term, the Division approved a reclamation plan allowing a delay in <br />contemporaneous reclamation under Rule 4.14.1(1)(c). The approval was granted due to <br />the nature of the operation plan, which involved concurrent mining of two separate <br />mining areas (north and south) with a single dragline, in the original permit area. Pit <br />development in both the north and south blocks began with an initial box cut. <br />Development progressed from each box cut in opposite directions at different times <br />during the operations plan. The sequence of pit development did not allow for <br />backfilling and grading to be completed within 180 days of coal removal. At the point <br />of maximum disturbance, there were projected to be two open pits within each mining <br />block. <br />Pursuant to Rule 4.14.1(1)(c), the Division approved a variance from the requitement <br />that rough backfilling and grading be conducted within 180 days following coal removal. <br />This variance applied to the entire original permit area. In addition, a variance from the <br />Seneca II-W Findings Document 52 June 12, 2006 <br />Permit Renewal No. 5 <br />