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The application states that the mining plan for the Seneca H-W Mine was developed in <br />conjunction with the Seneca H Mining Plan. The pit progression design was based on <br />standard mining practices, tried and proven at the analogous Seneca H Mine. The <br />backfilling and grading plan is found within Volume 13, Tab 20. The reclamation schedule, <br />including a request for a variance from the contemporaneous reclamation requirements of <br />Rule 4.14 is contained within Volume 12, Tab 19. <br />The applicant completed projections of overburden bulking, in order to project post-mining <br />topography within the mined area. The projections included within the original application <br />were completed prior to submittal in 1982. Subsequently, in connection with operations at <br />the existing Seneca H Mine, the applicant has completed topographic observations of <br />reclaimed land. These aerial observations have determined that the actual bulking factor <br />slightly exceeded the original projection (19.8% in the operator's terminology, versus 15.3% <br />projection). <br />In completing its review of the amended application, the Division converted the applicant's <br />analytical projections into an analytical format more familiar to the Division. The applicant <br />projected an average overburden swell factor (loose swollen overburden volume divided by <br />bank overburden volume) of 1.32. <br />Further, the applicant projected 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. Adjusted <br />for the possible 4.5 percent discrepancy in observed versus original projected bulking <br />discussed above, the post-mining topography might rise by an additional 1.8 feet, resulting <br />in an average post-mining topographic deflation of 2.8 feet. In either case, the projected <br />post-mining topographic configuration is considered by the Division to constitute an <br />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 mining <br />areas (north and south) with a single dragline, in the original permit area. Pit development <br />in both the north and south blocks began with an initial box cut. Development progressed <br />from each box cut in opposite directions at different times during the operations plan. The <br />sequence of pit development did not allow for backfilling and grading to be completed <br />within 180 days of coal removal. At the point of maximum disturbance, there were <br />projected to be two open pits within each mining block. <br />Pursuant to Rule 4.14.1(1)(c), the Division approved a variance from the requirement that <br />rough backfilling and grading be conducted within 180 days following coal removal. This <br />variance applied to the entire original permit area. In addition, a variance from the <br />requirement that there be no more than 4 spoil ridges behind the pit currently being work <br />Seneca II-W Findings Document 46 C1982057 <br />Permit Renewal No. 5 December 9, 2010