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1.0 GENERAL • Seneca Coal Company (SCC) has previously auger mined at Seneca II, Yoast, and II-W. Angering occu«ed in the mid- to late 1980's at Seneca II and from June 2000 to December 2001 at Yoast and II -W. Seneca proposes highwall mining at II-W shown on Exhibit 72-3, Operations Plan (Combined Mine Plan). Since the final highwall is the economic limit at which the dragline can uncover coal, other coal extraction methodology has to be utilized. Potentially recoverable reserves under and beyond the highwall would be lost if alternative recovery methods are not implemented. SCC has used angering in the past and experienced an unacceptably low recovery rate, therefore SCC is proposing to employ a highwall miner in place of the auger. The highwall miner is expected to have a higher in-place recovery rate and deeper seam penetration than experienced with the auger. tt is proposed to highwall mine the Wadge, Sage Creek, and Wolf Creek seams. Per regulation 4.23.2111 (there are no highwall miner regulations, therefore auger regulations will be followed) any auger (highwall miner) mining associated with surface mining activities shall be conducted to maximize recoverability of the coal reserves remaining after the surface mining activities are completed. After careful study and consideration of the potential for future underground mining, SCC has determined that access to potential underground reserves from the final highwall areas would • not be a feasible, economic, or practical undertaking. There are a variety of factors that influence this determination. • Known and inferred adverse geologic conditions including the extremely steep dip of the coal seams • Re-excavation of deeply backfilled pit areas would be required to establish face-up areas and entries • Currently used conventional or long-wall type coal recovery methods are not suited Tor the structural conditions in the areas to be highwall mined or the areas immediately adjacent • Short and long-term stability of the reclaimed spoils up•dip from the face-up area Surtace water control at the steeply dipping face-up areas • Surtace and mineral ownership required for access Based on the above factors, SCC requests that Rule 4.23.21111a1, Ibl. and Ic) be waived and that no pre-designed access areas to unmined coal be required in the mine plan. • Although it is SCC's intention to maximize coal recovery in all areas, it should be understood that during the course of highwall mining there could be areas where blocks of unmined coal will 6e unavoidably left. This statement is based on previous experience with auger mining and the results of the NSA, Geotechnical Design and Operational Considerations analysis. These locations will be determined as highwall mining operations proceed and will result from on-the-spot determinations of the PR04 12-4-1 Revised 04/04