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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 131-T 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 Utility Borehole Installation and Additional Boreholes(MR16-296, MR17104)
<br />Once development of the headgate, tailgate, and bleeder entries for the 9 -East Longwall Panel is completed, two
<br />utility boreholes, 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, two alternate locations
<br />have been identified for permitting of the 9 -East Utility Borehole Installation. The 9 -East Utility Borehole
<br />Installation will consist of a new light -use road, drill pad, two utility boreholes, a short powerline extension, and the
<br />portable skid -mounted dual exhauster units. Dependent on which location is selected, the two boreholes will
<br />extend from the surface to the Wolf Creek Seam at a depth of 1,040 to 1,090 feet. Two additional boreholes will be
<br />completed to provide the capability to monitor and control the atmosphere in the overlying sealed Wadge Seam
<br />workings. One of the additional boreholes will be drilled and completed from the existing 9 -East Borehole pad, the
<br />other will require construction of a new pad on the existing access road to the northeast of the existing pad.
<br />Site-specific investigations completed to support design and permitting for the borehole installation include a
<br />cultural resource survey, review of site-specific soil mapping, and wildlife consultation. The cultural resource
<br />survey results (08/15) are summarized by the survey report provided in Exhibit 6L, the soils information is
<br />provided in Exhibit 16C, and a wildlife consultation letter is included in Exhibit 23C. The proposed surface
<br />disturbance activities will not impact either identified cultural resource values or sensitive wildlife habitat. The
<br />perimeter of all areas to be disturbed will be clearly marked and construction drainage control measures (silt fences
<br />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 up to 2.0 feet of soil material from the road and pad disturbance areas.
<br />A maximum of approximately 5,200 cy of soil will be recovered and stockpiled from the road disturbance area, and
<br />approximately 6.680 cy from the pad area. An additional 700 cy of soil will be recovered from the additional pad
<br />area, and this material will be placed in the existing soil stockpiles. Natural vegetative materials incorporated into
<br />the 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 1,760 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 two alternatives in Exhibit 49EE. The road disturbance corridor will
<br />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 l OH: l V. Up to four 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. The new pad for the additional borehole will be approximately 80 x
<br />120 feet, as shown on Figure 49EE-F2. As shown on Figure EX49EE-F1, TC has identified two potential borehole
<br />locations, although only one location will ultimately be developed and completed. The drill pad size would be the
<br />same, regardless of location, and TC will permit and bond for the maximum road disturbance. Road and pad
<br />construction will involve placement of construction sediment controls, soil recovery, installation of drainage
<br />features, any necessary cut/fill work to establish the road profile and pad, and placement and compaction of
<br />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 />MR17-304 2.05-45.30 01/12/17
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