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5-Main North Borehole and Pipelines (MR14-283, MR15-288, TR16-84) - In order to provide concrete for the
<br /> planned Wolf Creek ramp development and construction activities, TC completed a cement borehole, located over
<br /> our 5-North Mains, extending into the existing Wadge Seam Mains. The borehole extends to a depth of
<br /> approximately 1,500 feet,was drilled to a 12.25-inch diameter, and cased to a 9.875-inch diameter.
<br /> The borehole is accessed from the paved County Road (RCR33), using the existing established access for the 6-
<br /> Main North Shaft Facility, with a new light-use road to the borehole pad location, as shown on Map 24 (4/4) and
<br /> Figure 49CC-Fl. The borehole required construction of approximately 0.6 mile of new light-use road from the
<br /> existing established 6-Main North access road. A new borehole pad (approximately 200 x 'qr' ft) vas constructed
<br /> to support the initial drilling and borehole completion activities, subsequent cement delivery and tted operations,
<br /> and planned future activities. The 5-Main North(5N/IN) Cement Borehole installation consists of .ie new light-use
<br /> road and borehole pad; adjacent soil material stockpiles, and the lined and grouted borehole extending into the 5-
<br /> North Mains in the Wadge Coal Seam. The road disturbance corridor is 40 feet wide, although the actual road
<br /> surface is only approximately 24 feet wide. The total road disturbance is approximately 3.1 acres, and the
<br /> maximum pad disturbance is approximately 0.9 acre.
<br /> Site-specific investigations required for design and permitting of the cement corehole include a cultural resource
<br /> survey and wildlife consultation. The cultural resource survey results are summarized by the survey report provided
<br /> in Exhibit 6T, and a wildlife consultation letter is included in Exhibit 23C. The perimeters of all disturbed areas are
<br /> clearly marked and construction drainage control measures (silt fences or wattles) were installed prior to disturbance.
<br /> In order to reestablish effective vegetative cover during site reclamation, TC recovered and stockpiled a maximum of
<br /> 1.0 foot of soil material from the road and pad disturbance areas. A maximum of approximately 5,060 cy of soil was
<br /> recovered and stockpiled from the road disturbance area, and approximately 1,480 cy from the pad area. Natural
<br /> vegetative materials incorporated into the salvaged soil materials and seeding with the soil stockpile stabilization seed
<br /> mixture will assist in stabilizing the stockpiled soil material and preventing erosion or loss of the soil materials.
<br /> The pad and road location are on a minor ridgeline, so upgradient drainage will be limited. The limited amount of
<br /> drainage from upgradient areas will be intercepted and routed around the borehole pad by a small upgradient diversion
<br /> ditch on the north side of the pad and the road will not cross any natural drainages, so no culvert installations are
<br /> needed. Drainage from the small borehole pad area will be controlled under a Small-Area Exemption by gravel
<br /> surfacing on the pad surface, the upgradient diversion ditch which will drain through a rock sediment basin to the
<br /> adjacent natural drainage,and temporary revegetation seeding of pad cut/fill areas.
<br /> Road construction involved soil recovery, scarification and recompaction of surface materials, any necessary cut/fill
<br /> work to establish the road profile, and placement and compaction of approximately 3 inches of suitable road-base
<br /> materials and 8 inches of pit-run gravel. Given the location of the borehole pad on top of the ridge and the relatively
<br /> short access road, it is not anticipated that any truck turn-outs will be needed. The 24-foot road surface is graded and
<br /> crowned to promote effective drainage.
<br /> Construction of the borehole pad involved soil recovery, installation of the upgradient diversion, cut/fill pad
<br /> construction, and placement of gravel surfacing material to control dust and sediment from the pad area. Borehole
<br /> completion involved drilling, installing, and grouting a 14-inch diameter steel surface casing in place to a depth of
<br /> approximately 40 feet (dependent on the ground conditions encountered). The borehole was then advanced, using
<br /> directional drilling, to a depth of approximately 1,500 feet to intercept the mine workings. Water, drilling fluids, and
<br /> cuttings were contained within one or more excavated pits or portable steel tanks (porta-pits) on the borehole pad.
<br /> The borehole was drilled at 12.25 inches, and cased and grouted to a nominal diameter of 9.875 inches. A collar for
<br /> pumping the concrete was fitted to the cased wellhead. Concrete is delivered by mix trucks, dropped down the
<br /> borehole,and transferred underground to the ramp construction area using a pipeline or underground equipment.
<br /> In conjunction with the planned Wolf Creek Reserve development and mining operations, TC anticipates the need
<br /> to dewater two large bodies of water which have accumulated in the sealed and abandoned mine workings in the
<br /> Wadge Seam. In preparation for these dewatering activities, TC plans to convert the existing 5-Main North(5MN)
<br /> borehole to a dewatering borehole, and to install approximately 5,000 feet of buried water pipeline to route the
<br /> water to the mine water handling system and to provide a tap for a planned future mine water treatment system.
<br /> The dewatering borehole, water transfer pipelines, and associated valving will allow water pumped from the Wolf
<br /> Creek Reserve mine workings and the overlying accumulations of water in the sealed and abandoned Wadge Seam
<br /> workings to be transferred to the existing 6-Main North(6MN)Reservoir, the existing 10-Right water
<br /> TR16-84 2.05-45.26 06/20/16
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