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proximity of existing ranch roads, TC does not plan or anticipate the need for new road construction to access the
<br />drill -site. With dry ground conditions, drilling equipment and supplies should be able to travel the short distance
<br />overland from the existing roads to the drill -site, without significant surface disturbance. Installation of the
<br />dewatering borehole will involve placement of construction erosion controls (silt fence and/or straw wattles) around
<br />the downslope margins of the drill pad, removal and windrowing of available soil materials from a maximum 100 x
<br />150 foot (0.35 acres) pad area, grading to establish a level drill -pad, excavation of one or more temporary cuttings
<br />pits on the drill -pad, drilling and casing of the borehole, and installation of a protective access manhole. During
<br />drilling, a 14 -inch diameter steel casing will be placed and grouted in the borehole. On completion of drilling and
<br />casing operations, the cuttings pits will be allowed to dry -out, material excavated from the pits will be replaced and
<br />graded, a protective cover consisting of an 10 -foot length of 8 -foot diameter CMP with steel lid and with lightening
<br />protection will be installed, a 400hp submersible downhole pump will be installed in the well, and the pad surface
<br />will be seeded to control erosion and sediment.
<br />Pipeline installation will involve removal and windrowing of soil materials from the pipeline construction corridor
<br />(maximum - 50 -foot wide) to one side; trenching, with the excavated material to be placed on the opposite side;
<br />placement of suitable bedding materials; placement, connection, and pressure testing of the pipeline; backfilling
<br />and compaction of suitable fill materials around and over the pipeline; backfilling and compaction of the trench;
<br />regrading; replacement of soil materials; and revegetation of all disturbed areas. The pipeline will be constructed
<br />using high-strength fused HDPE pipe, buried approximately 5 -feet deep. A maximum of five access/inspection
<br />manholes will be located at key points along the pipeline route. A power distribution line will be extended
<br />approximately 6,800 feet from the 6MN Ventilation Installation, to provide power for the 19 -Right Dewatering
<br />Borehole. Powerline installation will require installation of approximately 25-35 powerpoles, and a pole -mounted
<br />transformer will feed the required pump supply and controls within the borehole manhole structure. Powerpoles
<br />will include installed raptor protection to minimize the potential for electrocution and discourage use as perches.
<br />During construction, and for the minor surface structures that will remain during mining, drainage and sediment control
<br />will be provided by Alternative Sediment Controls (ASC's) consisting of combined Best Management Practice (BMP)
<br />measures. Construction -related surface disturbance will be limited to soil removal and windrowing from the pipeline
<br />trench alignments and stockpiling for the borehole pad area, excavation of the trenches and temporary stockpiling of
<br />excavated material adjacent to the trench, minor cut/fill grading to establish the borehole drill -pad, and excavation of
<br />temporary cuttings pits. The pad for the 19RT Mine Dewatering Borehole installation has been designated as a Small
<br />Area Exemption (SAE), and the limited drainage from this area will be controlled by staked straw wattles, and
<br />reclamation/stabilization of the pad area following well installation. Temporary drainage and sediment control
<br />measures will remain in-place until vegetation is sufficiently established to effectively control runoff, erosion, and
<br />sediment loss.
<br />Following installation of appropriate ASC's for each portion of the project disturbance, available soil materials will be
<br />bladed from any new disturbance areas and temporarily windrowed or stockpiled on the upgradient edge of these
<br />disturbance areas. For pipeline trench areas, consideration of soil horizon segregation must be balanced with the
<br />objective of limiting overall surface disturbance. In the interest of minimizing overall surface disturbance, TCC
<br />proposes to not segregate and separately stockpile individual soil horizons for the pipeline trench disturbance, and
<br />submits that this approach will not significantly alter soil suitability characteristics, since the differences between the
<br />soil horizons is not significant over the areas to be affected by trenching. For the borehole drill -pad, individual soil
<br />horizons will be segregated, if present.
<br />Soil materials will be replaced following completion of pipeline installation. Reseeding of the disturbed areas will
<br />be completed during the first appropriate planting period following soil material replacement. When no longer
<br />needed to support ongoing or future mining and related operations, the dewatering borehole will reclaimed by
<br />removing the surface manhole structure, plugging and sealing the borehole, consistent with State Engineer
<br />requirements; cutting -off the casing below ground level, and placing a permanent marker; then regrading, replacing
<br />soil materials, and reseeding the associated disturbance area. Pipelines will be abandoned in-place, with the ends of
<br />the pipelines cut-off and capped below grade.
<br />5 -Main North Borehole and Pipelines and Future Passive Water Treatment System (MR14-283, MR15-288,
<br />MR16-295) — In conjunction with the planned Wolf Creek Reserve development and mining operations, TC
<br />anticipates the need to dewater two large bodies of water which have accumulated in the sealed and abandoned
<br />MR16-299 2.05-50.10 06/16/16
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