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Sedimentation Pond A receives runoff and limited spoil spring discharge from the reclaimed and bond-released
<br /> Eckman Park surface-mined areas. The Pond is used as a supplemental water supply for the current mining
<br /> operations, for recreation for mine employees (stocked with trout for fishing), and discharge from the Pond
<br /> provides for sustained flows through-out most of the year in Foidel Creek. As an MSHA impoundment, Pond A is
<br /> subject to regular monthly inspections, except during the winter months. For the MSHA inspections, the outlet
<br /> works and pond embankment are inspected, and any necessary repairs made on a timely basis.
<br /> Treatment Facility B receives runoff from the Tipple area, including the Belt-Out-Back (BOB) Stockpile.
<br /> Upstream of the treatment facility is a clean-out sump, which captures wash-down flows and sediment from the
<br /> Tipple. This sump is cleaned-out periodically throughout the year. The treatment facility itself is comprised of an
<br /> H shaped pond, which discharges to Foidel Creek. During the fall, under low-water conditions, the pond will be
<br /> visually inspected to determine if there is a significant sediment delta at the pond inlet. If so, a long-reach backhoe
<br /> will be used to remove the accumulated sediment, and the excavated material will be loaded and hauled to the
<br /> refuse pile for disposal. During the quarterly pond inspections, the Facility B flume will be visually inspected to
<br /> assess whether or not it remains level and in good working condition. Repairs, such as leveling, assuring free
<br /> discharge, and removal of accumulated sediment in measuring devices will be done on an as-needed basis. The
<br /> facility will be removed when it is no longer needed. The H shaped pond will be backfilled with material from
<br /> adjacent areas, graded to blend with the surrounding terrain,topsoiled, and revegetated.
<br /> Sedimentation Pond C controls runoff from the old Train Loadout area, which has been converted to the Truck
<br /> LoadOut. Historically, the pond has discharged infrequently, and holds only a very limited amount of water during
<br /> spring runoff. TC will inspect the pond for any significant sediment accumulations in the fall. The same criteria
<br /> note for Pond B will be used to determine if the pond requires cleaning. If so, the material will be removed and
<br /> hauled to the refuse pile for disposal. During the quarterly pond inspections, the outlet works of Pond C are
<br /> inspected to determine if any maintenance work is required. Any required maintenance work is noted and
<br /> completed within a reasonable time period following the inspection. When the pond is longer needed it will be
<br /> removed. The outlet works will be removed, the embankment pushed in and graded to blend with the surrounding
<br /> terrain, topsoiled, and revegetated.
<br /> Sedimentation Pond D controls runoff from a portion of the surface facilities area, discharge from the Area I Pit,
<br /> runoff from the Refuse Pile, minor amounts of underground mine discharge (also from the Area 1 Pit), and will
<br /> receive and control discharge from a temporary Water Treatment Pilot Installation during a brief test period. In
<br /> general, because the Area 1 Pit is part of the mine-water collection and recycle system, discharge from the Area 1
<br /> Pit or underground mine discharge occurs rarely, if ever, since process water demand equals or exceeds normal
<br /> flows to the Area 1 Pit. During Permit Renewal 3, TC contracted with Montgomery Watson to review the design of
<br /> Pond D. The resulting design review report is provided in Exhibit 8H(1). At one point in time, an aerator was
<br /> installed in Pond D to promote aerobic conditions throughout the year. There is an existing powerline and power-
<br /> box on the west side of the pond. The aerator and power supply will be removed prior to reclamation of the pond.
<br /> With construction and initiation of operations for Washplant II, process water withdrawals from the Area 1 Pit for
<br /> the Washplant have been balanced with inputs to meet process demands and maintain a stable water level in the Pit
<br /> (well below the maximum design water level). The Washplant 11 construction encroached on the Pond D
<br /> emergency spillway, so the spillway was relocated to a location near the principal spillway riser on the Pond
<br /> embankment. Spillway dimensions and configuration were preserved, and the new spillway location provides for
<br /> better routing through the pond, increasing the distance between the eastern pond inlet and the spillway.
<br /> TC will vivally inspect Pond D in the fall to for any significant sediment accumulations. The same criteria will be
<br /> used to determine if the pond requires cleaning. If so,the material will be removed and hauled to the refuse pile for
<br /> disposal. The pond is inspected during the regular CPDES samplingand quarterly pond inspections, and the flume
<br /> is checked to determine if it is functioning correctly. Any problems are noted and repairs made as-needed. Pond D
<br /> is also an MSHA pond, subject to regular monthly inspections, except during the winter months. For the MSHA
<br /> inspections, the outlet works and pond embankment are inspected, and any necessary repairs made in a timely
<br /> basis. The pond will be removed when it is no longer needed. . The outlet works will be removed, the rock in the
<br /> emergency spillway may be reclaimed or placed in the pond basin,the embankment will be pushed in and graded to
<br /> blend with the surrounding terrain, and the area will be topsoiled and revegetated.
<br /> RN 17-07 2.05-77 02/15/18
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