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Explosives will be used to fragment overburden and exposed coal at the Seneca II-W Mine. Seneca Coal Company typically will use ammonium nitrate and fuel oil (ANFO) for this purpose, primed with cast primers and detonated with detonating cord. A certified blaster will be in charge of all blasting operations to ensure compliance with State and Federal laws. Additional information regarding planned blasting operation is located in Volume I1, Tab 14 of the permit application package. Seneca submitted a revision to the permit application to establish maximum allowable ground vibrations from blasting, as a result of damage to private property, including oil tanks and an oil well. Seneca will maintain peak particle velocities at the oil well site of five inches per second (ips) or less, and will utilize a seismic monitor at the well site to verify maximum peak particle velocities. Seneca also increased the bore hole column stem in areas where mud seams are encountered in the upper strata. These plans are implemented within 1,000 feet of the Meridian Oil Well. VII. Backfilling and Grading The application states that the mining plan for the Seneca II-W Mine was developed in conjunction with the Seneca II Mining Plan. The pit progression design was based on standard mining practices, tried and proven at the analogous Seneca II Mine. The backfilling and grading plan is found within Volume 13, Tab 20. The reclamation schedule, including a request for a variance from the contemporaneous reclamation requirements of Rule 4.14 is contained within Volume 12, Tab 19. 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 in 1982. Subsequently, in connection with operations at the existing Seneca II Mine, the applicant has completed topographic observations of reclaimed land. These aerial observations have determined that the actual bulking factor slightly exceeded the original projection (19.8% in the operator's terminology, versus 15.3% projection). In completing its review of the amended application, the Division convened the applicant's analytical projections into an analytical format more familiar to the Division. The applicant projects an average overburden swell factor (loose swollen overburden volume divided by banl: overburden volume) of 1.32. Further, the applicant projects a bulking factor (swollen backfilled volume divided by excavated pit volume) of 0.91. Considering the average mined depth and extracted seam thickness, this suggests an average post-mining topographic deflation of 4.6 feet. Adjusted for the possible 4.5 percent discrepancy in observed versus original projected bulking discussed above, the post-mining topography might rise by an additional 1.8 feet. Seneca 11-W Findings Document 35 June I5, 2001 Permit Renewal No. 3