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a nominal diameter of 4.5 inches. A collar for pumping the concrete will be fitted to the cased wellhead. Concrete
<br />will be delivered by mix trucks, dropped down the borehole, and transferred underground to the construction area
<br />using a pipeline or underground equipment.
<br />The 13LT Outby Utility Borehole installation will remain in-place until the planned construction activities are
<br />completed, and will then be reclaimed. Reclamation of this installation will involve plugging and sealing the
<br />borehole, regrading the pad and road to their approximate original configuration, soil material replacement, and
<br />reseeding with TC's standard Rangeland Seed Mix.
<br />9 -East Utilitv Borehole Installation (MR16-296
<br />Once development of the headgate, tailgate, and bleeder entries for the 9 -East Longwall Panel is completed, a
<br />utility borehole, connected to monitoring equipment and dual exhauster units on the surface, will be completed at
<br />the back of the bleeders to facilitate monitoring and control of conditions in the gob or bleeders which could
<br />contribute to or result from spontaneous combustion. Given that the eastern limit of the 9 -East Panel will be
<br />determined by the coal seam and ground conditions encountered as mining reaches this area, three alternate
<br />locations have been identified for permitting of the 9 -East Utility Borehole Installation. The 9 -East Utility
<br />Borehole Installation will consist of a new light -use road, drill pad, two utility boreholes, a short powerline
<br />extension, and the portable skid -mounted dual exhauster units. Dependent on which location is selected, the two
<br />boreholes will extend fi-om the surface to the Wolf Creek Seam at a depth of 1,040 to 1,090 feet.
<br />Site-specific investigations completed to support design and permitting for the borehole installation include a
<br />cultural resource survey and wildlife consultation. The cultural resource survey results are summarized by the
<br />survey report provided in Exhibit 6T, and a wildlife consultation letter is included in Exhibit 23C. The proposed
<br />surface disturbance activities will not impact either identified cultural resource values or sensitive wildlife habitat.
<br />The perimeter of all areas to be disturbed will be clearly marked and construction drainage control measures (silt
<br />fences or wattles) will be in place prior to disturbance. In order to reestablish effective vegetative cover during site
<br />reclamation, TC will recover and stockpile a maximum of 1.5 feet of soil material from the road and pad
<br />disturbance areas. A maximum of approximately 5,070 cy of soil will be recovered and stockpiled from the road
<br />disturbance area, and approximately 5,000 cy from the pad area. Natural vegetative materials incorporated into the
<br />salvaged soil materials and seeding with the soil stockpile stabilization seed mixture will assist in stabilizing the
<br />stockpiled soil material and preventing erosion or loss of the soil materials. Soil material stockpiles will be located
<br />at reasonable intervals along the road and adjacent to the pad area, and drainage from the stockpiles will be
<br />controlled by placing straw wattles, silt fence, or similar materials downgradient from the piles.
<br />The 9 -East Utility Borehole Installation will be accessed from County roads RCR33 and RCR179, using the
<br />existing established Fish Creek Tipple and 18 -Right Shaft roads. From the 18 -Right Shaft Road, a maximum of
<br />approximately 2,300 feet of new light -use road will be constructed to access the borehole location, as shown on
<br />Map 24, and the series of figures reflecting the three alternatives in Exhibit 49EE. The road disturbance corridor
<br />will be 40 feet wide, although the actual road surface will only be approximately 24 feet wide. The road will be
<br />constructed on a compacted base with 8 -inches of pit -run material, surfaced with 8 -inches of gravel. Road cut and
<br />fill slopes will be a maximum of 2H:1 V and overall road gradient will not exceed IOH:1 V. Up to five 24 -inch
<br />culverts will be installed along the road to pass natural drainage under the road. A borehole pad (surface area of
<br />approximately 200 x 200 ft.) will be constructed to support the initial borehole drilling, subsequent borehole
<br />completion activities, and future site activities. As shown on Figure EX49EE-F1, TC has identified three potential
<br />borehole locations, although only one location will ultimately be developed and completed. The drill pad size
<br />would be the same, regardless of location, and TC will permit and bond for the maximum road disturbance. Road
<br />and pad construction will involve placement of construction sediment controls, soil recovery, installation of
<br />drainage features, any necessary cut/fill work to establish the road profile and pad, and placement and compaction
<br />of approximately 3 inches of suitable road -base materials and 8 inches of pit -run gravel for the road, and gravel
<br />surfacing on the pad. The 24 -foot wide road surface will be graded and crowned to promote effective drainage.
<br />The total road disturbance will be approximately 2.09 acres, and the maximum pad disturbance (including cut/fill
<br />slopes and diversion ditches) will be approximately 2.07 acres.
<br />The proposed pad and road location are on a low -gradient sidehill, so upgradient drainage will be limited. The
<br />limited amount of drainage from upgradient areas will be routed under the road through culverts or intercepted and
<br />routed around the borehole pad by a small perimeter diversion ditch on the east, south, and west sides of the pad,
<br />MR 16-296 2.05-45.30 05/03/16
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