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Twentymile Coal, LLC (TC) Geologic and Engineering Data Report Lease by Modification Application — Wolf Creek Reserve April 2014 Special stipulations N/A II. MINE PLAN SECTION A. Mine plan scenario Possible mine plans The depth of the coal deposit precludes cost-effective surface mining. Conventional room and pillar mining would be acceptable only if the tract were to be bypassed otherwise. The most efficient underground method currently in widespread use is the continuous miner and shuttle car system used for entry development, combined with longwall equipment for coal production. The depth and thickness of the Wolf Creek Seam is well-suited for the existing longwall equipment and conventional underground development methods currently used by TC in the Foidel Creek Mine. The Wolf Creek Seam would be accessed from the existing Wadge Seam workings by driving declining rock -slope ramps down from the Wadge Seam to the Wolf Creek Seam. Briefly, conventional continuous miner sections develop a main entry system off which the three - entry head -gate and three -entry tailgate are driven at right angles to the mains. The gate entries are separated by approximately 1,000 feet, and are designed to be as long as possible in order to maximize the efficiency of the longwall. The longwall equipment is moved in and installed in a setup room mined between the headgate and tailgate entries. The longwall mining method mines the block of coal between the head -gate and tailgate entries by cutting the coal with a rotary shearer, while temporarily supporting the roof in the immediate mining area with movable hydraulic shields. The back, or roof, caves in behind the shields as the longwall face advances. A chain conveyor transports coal from the longwall face to a conventional rubber belt conveyor. The belt conveyor transports the coal outside for processing, shipping, and sale. As the coal is cut and removed, the shields move forward, and the process is more or less continuous. Recovery within the actual longwall panel itself is nearly 100 percent. 2. Company data provided Data from fifteen underground and surface drillholes was used to draw lithological cross sections and to generate the coal quality tables. A print-out of this data in Table 1 includes the drillhole numbers, the Wolf Creek Seam and mining height thicknesses and general quality data at a 1.5 specific gravity. Map data includes the following key elements: subsurface mapping data (overburden, interburden, and coal bench thickness), geologic data, topography, drillhole locations and numbers, public land survey system grid, mine coordinate system, and underground mine scenario (mine development and longwall layout). This map data was used to produce the illustrative maps included in this report. Evaluation and recommendations The methods and mine plan proposed by TC (Refer to Plate 7) will result in Maximum Economic Recovery of the Wolf Creek Seam coal within the proposed lease modification area and the planned mining area, and in addition, will contribute to overall coal recovery and Maximum Economic Recovery for the adjacent federal and private coal leases. Given the benefits of producing and making the available coal resource available as a quality, low-cost energy source, the probability of achieving Maximum Economic Recovery, and the associated labor, economic, and community benefits, the proposed lease modification application should be approved and the modified lease WCR BLM Lease App Geologic & Engineeering Data Report 0414.docx Page 5