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reducing reagent may be injected into the treated water if required. After treatment, water flows from the treatment
<br />• ponds through a discharge ditch to Fish Creek. A portable structure, approximately 20 x 8 x 8 feet, placed on the north
<br />light-duty road for the easternmost cell of the treatment facility, houses storage containers of NaOH and equipment for
<br />metering and injecting the reagent. An additional structure, approximately 32 x 8 x 8 feet, will be placed adjacent to
<br />this existing structure to house a larger storage container for NaOH. A smaller portable structure, approximately 8 x 8
<br />x 6 feet, placed on the west light-duty road for the westernmost pond, houses storage containers of HzSO4 and
<br />equipment for metering and injecting. Overhead power is provided to all of these structures, via pole-mounted lines
<br />from the substation. Three to five additional poles will be set to provide power to the remote monitoring equipment.
<br />Barricade Chamber/FCM-2 Borehole
<br />As a consequence of TCC's plans to develop 22,000 foot long mining panels, MSHA required that mid-panel barricade
<br />chambers, or alternate escape and supply provisions be established to assure the safety of miners working on the panels.
<br />A Barricade Chamber was established underground, and connected to the surface by a 4-foot diameter drilled shaft and
<br />a 6-inch diameter cased borehole, for the purpose of providing air, water, food, first aid supplies, etc., in the event of an
<br />emergency. Surface disturbance typical of exploration drill-pad development is associated with the Barricade Chamber
<br />shaft and borehole.
<br />The shaft and borehole developed to serve the 9-Right and 10-Right gate-road barricade chambers are located in
<br />Sections 22 and 21 respectively as depicted on Figure 16B. Both sites are located on previously cultivated croplands.
<br />Each site was accessible from existing ranch roads located in the general vicinity. No access improvements were
<br />required, providing the sites were accessed and developed during dry weather or periods when the ground was frozen.
<br />No regular periodic access requirements pertain to these sites. In the event of poor ground conditions during
<br />development or for subsequent access to these sites, TCC retained the flexibility to windrow topsoil from the access
<br />routes, as appropriate, to assure protection of the topsoil resource.
<br />Surface disturbance for each site is minimal and consists of an area encompassing approximately 100 x 100 feet.
<br />Topsoil from the drill-pad and mud-pit areas was salvaged and stockpiled adjacent to each drill-site. Approximately
<br />26 inches of the Binco silty clay loam was salvaged, based upon the existing soils mapping for each site. Following
<br />topsoil salvage, each drill-site was leveled and mud pits developed. Site drainage was configured to contain surface
<br />runoff from the site within the mud-pit areas. Secondary sediment control measures consisting of silt fences or hay
<br />bales were utilized as necessary to minimize sediment transport from each site. For both the shaft and borehole, the
<br />shaft collar and casing extend above ground elevation. Protective shelters/covers of wood frame and/or metal
<br />construction were constructed on concrete foundations over the shaft and borehole casing. Following completion of
<br />drilling activities, the mud pits at each site, once suitably dry, were backfilled. The sites were regraded, topsoil
<br />redistributed, and the areas seeded with the appropriate seed mix at the first appropriate seeding opportunity.
<br />Given that the Barricade Chamber is no longer needed for mine safety purposes (function is now addressed by mine
<br />escapeway plans utilizing fresh-air returns and escape elevators), the Barricade Chamber and associated shaft have
<br />been sealed, with bulkheads at the top and bottom of the shaft, are now used for mine water storage, and the protective
<br />shelters have been demolished, with the foundations remaining in-place. The shaft collar and borehole casings are
<br />now covered by locked steel caps, as a security and safety measure. Existing mine water transfer pipelines connect to
<br />the Barricade Chamber/FCM-2 boreholes from the Fish Creek Water Treatment Facility and l ORT Dewatering Wells,
<br />allowing water to be transferred from these locations to the mine water system. An additional transfer pipeline,
<br />approximately 8,560 feet long, will be extended from the Barricade Chamber/FCM-2 boreholes to the new Fish
<br />Creek/Area 1 Pit Transfer Pipeline, to. allow water to be transferred directly from this location to the Area 1 Pit Mine
<br />Water Storage Reservoir. The pipeline will be laid in existing pipeline and road corridors to minimize new
<br />disturbance, and will be welded 12-inch 1-1DPE pipe, buried approximately 5 feet deep, connecting to the Fish
<br />Creek/Area 1 Pit Transfer Pipeline at a CMP or concrete culvert manhole enclosing the pipeline control valves. For
<br />all pipeline construction, soil material will be removed and temporarily windrowed on one side of the trench, with
<br />• trenched material placed to the other side. Once the pipeline is placed, properly bedded, connected, and leak tested,
<br />trenched material will be backfilled and compacted, and soil material will be replaced over the excavation and
<br />reseeded.
<br />MR08-230 2.05-50.3 11/20/08
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