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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 />• <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 />MR 10 -251 2.05 -50.8 01/07/11 <br />