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1111 ENERGY
<br />Twentymile Coal, LLC "-,_.
<br />SCANNE'r`
<br />- In
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<br />Mr. Jared Ebert, Environmental Protection �)pecialtst
<br />Division of Reclamation, Mining, and Safety
<br />Divisionng & safety�on,
<br />1313 Sherman Street, Room 215
<br />Denver, Colorado 80203
<br />29515 Routt County Road 27
<br />Oak Creek, CO 80467
<br />970.879.3800
<br />NovembeW hVED
<br />Nov 16 'ZO15
<br />(303) 866-3567 X 8120
<br />Division of Reclamation,
<br />Mining & Safety
<br />RE: Twentymile Coal, LLC - Foidel Creek Mine (Permit No. C-82-056), Minor Revision
<br />(MR15-291) —13 -Left Outby Utility Borehole
<br />Dear Mr. Ebert:
<br />Twentymile Coal, LLC (TC) requests CDRMS approval of a Minor Revision to our existing approved
<br />Permit for installation, operation, and reclamation of a new utility borehole, to be located over the 13 -
<br />Left Outby Gateroad. As the 12- and 13 -Left outby panels approach the Main Entries and fault zone,
<br />the cross -panel grade at the end of the panels increases to the point where it may affect the stability of
<br />the longwall during the final cut and recovery phase. The purpose of the borehole is to allow concrete
<br />to be transferred from the surface to the end of these two panels, to facilitate pouring of a "wedge" at
<br />the end of each panel to level the operating surface during the final cut and recovery phase. The
<br />borehole will extend to a depth of approximately 1,270 feet, will be drilled and subsequently reamed to
<br />a maximum 10 -inch diameter, and cased to a 4.5 -inch diameter. The proposed borehole will be
<br />accessed from the paved County Road (RCR33), using the existing established 6 -Main North mine
<br />road. From the 6 -Main North Road, approximately 1,550 feet of an existing two -track ranch road
<br />ranch will be upgraded, and 1,000 feet of new road will be constructed to access the borehole location,
<br />as shown on Map 24, and in Exhibit 49DD.
<br />In addition to the road upgrades and new road construction road construction previously described, a
<br />new borehole pad (maximum of approximately 200 x 200 ft.) will be constructed to support the initial
<br />borehole drilling, subsequent borehole completion activities, and delivery and transfer of concrete.
<br />The 13 -Left Outby Utility Borehole installation will consist of the upgraded/new access road, the new
<br />borehole pad; adjacent soil material stockpiles, and a cased and grouted borehole extending into the
<br />existing Wadge Coal Seam mine workings. The proposed pad and access road locations are on a low -
<br />gradient side -hill, so upgradient drainage will be limited. The limited amount of drainage from
<br />upgradient areas will be intercepted and routed around the borehole pad by a small upgradient
<br />diversion ditch on the southwest and northwest sides of the pad. The existing ranch road crosses a
<br />small ephemeral drainage, and the existing culvert will remain in-place (may be necessary to extend
<br />this culvert). Drainage from the borehole pad will be controlled under a Small -Area Exemption, with
<br />gravel surfacing on the pad and road to control runoff and sediment, and placement of rigid sediment
<br />filter material on the northeast side of the pad area. The 13 -Left Outby Utility Borehole installation
<br />will remain in place for up to two years to facilitate transfer of concrete to the underground workings,
<br />and will then be reclaimed. Reclamation of this installation will involve plugging and sealing the
<br />borehole, regrading the pad and road, soil material replacement, and reseeding.
<br />This submittal includes revised PAP text, exhibits; and maps, addressing the location, configuration,
<br />operation, maintenance, and reclamation of the proposed 13 -Left Outby Utility Borehole installation.
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