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The other paremetera used by COV in arriving at the revised mina plan; spontaneous combustion, ventilation, cleat system, ^tructural geology,.and ^ubsidanca are also • well supported by both mining experience on the property and variou^ regulatory requirements. The exclusion of coal outcrop erase from the reserve base and mina plan era reasonable and prudent given the known apontaneoue combustion tendencies of the coal, particularly near previously heated areas close to the burn line. Tha 1986 fire, while almost certainly directly ceased by the large differential air pressure acroae the pillars, wa• also linked to surface subsidence and air entry from the surface in the general area due to vary high coal extraction of the near outcrop coal on C-15079 adjacent to the mains. In near outcrop production panels, obtaining good seals from uncontrolled outside air ingress through ehsllow cover subsidence cracking, ie not seeurad. Given the possible consequences of a large fire, with the possible lose of life and loss of the remaining coal resource, the exclusion of production panels from suspect outcrop areas ie well justified. The production panel bleeder eyatam design, which reduces panel recovery beeauee of the two row^ of piller• left to support the panel blander entries, i• unavoidable again given the susceptibility of other bleeder systems to spontanaou• combustion and the present regulatory requirements of NSHA. Siting of additional ventilation intakes sway from the outcrop, and limiting the gross srea of the mine needing to be ventilated at a given time, both work to lower air pressure differential• acroe• pillars separating intake frao exhaust airways, and tbua lower the possibility of spontaneous combustion within the mina. The orientation of all production panels in the mina at 45 degrees to the cleat i^ identical to the existing mine plan and is common in the industry to minimize rib problems and make coal cutting easier. While the rigid adherence to thi^ orientation in places results in lost coal, the snticipated benefits with regard to increased roof stability, (for thi^ property a much more sariou• concern) outweigh the lost coal. Tha knowledge of the structural geology of the property, which 1• far from complete, primarily consists of offset and orientation of several faults, thaw being large enough to limit the extant of soma of the production panels. Thaee faults, and other suspected faults, work against any serious consideration of longwalling the property, which would be a higher recovery production method much better suited to the poor roof conditions. Areas restricted to development mining only, due to possible impacts of surface resources by subsidence, era dictated by State and Federal regulations that era out of the company's contcol and must be accepted ae aacrifica areas of the coal reserves within them. Summary of Compliance COV•s proposed major revision to the existing R2P2 for the Orchard Valley property is wall supported both by mining experience gained in tan years of production from the property and the conclusions of a detailed, comprehensive geologic model of the property as it relates to the remaining recoverable reserves and their economic extraction. The;degree of analyei^ applied to the property to arrive st the recalculated recoverable reserves, and the proposed mina plan to extract them, is adequate to meet the requirements of the 43 CFR 3480 regulations, including lgR, and ie in compliance vlth the Mineral Leasing Act. Accordingly, approval of the revised Cyprus Orchard Valley Revised Mining and Reclamation Plan ie recommended. Ed bi,.ouves GTRA M,.;..f ~„y,.~~, ~'~~,9~