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Maintenance, operation, and removal requirements for each of the sedimentation ponds and treatment
<br />facilities are similar, however, specific details relative to each are described separately in the following
<br />sections.
<br />Treatment Facility B receives runoff from the Tipple azea, 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
<br />the Tipple. This sump is cleaned-out periodically throughout the year. The treatment facility itself is
<br />comprised of an H shaped pond, which dischazges to Foidel Creek. TCC will survey the facility every three
<br />years, with the date of the 1999 Permit Renewal being year one. Therefore, the survey will be conducted
<br />during 2001. The survey will be used to determine if sediment removal is required, with the criteria that
<br />sediment accumulation increased by 40 percent from the prior survey. If sediment removal is required, the
<br />dredged material will be brought to the refuse pile or pit for disposal. During CDPS field monitoring, the
<br />Facility B flume will be visually inspected to determine that it is working correctly. Repairs, such as
<br />leveling, assuring free dischazge, and removal of accumulated sediment in measuring devices will be done on
<br />an as-needed basis. The facility will be removed when it is no longer needed. The H shaped pond will be
<br />backfilled with material from adjacent areas, graded to blend with the surrounding terrain, topsoiled, and
<br />revegetated.
<br />The Sedimentation Pond C structure controls runoff from the old Train Loadout area, which has been
<br />converted to the Truck Loadout. Historically, the pond has discharged infrequently, and holds only a very
<br />limited amount of water during spring runoff. TCC will survey the pond per the schedule for Treatment
<br />Facility B. The same criteria will be used to determine if the pond requires cleaning. If so, the material will
<br />be removed and hauled to the refuse pile or pit for disposal. During the quarterly pond inspection, the outlet
<br />works of Pond C are inspected to determine if any maintenance work is required. Any required maintenance
<br />work is noted and completed within a reasonable time period following the inspection. When the pond is
<br />~~ longer needed it will be removed. The outlet works will be removed, the embankment pushed in and graded
<br />to blend with the surrounding terrain, topsoiled, and revegetated.
<br />Sedimentation Pond D controls runoff from a portion of the surface facilities azea, discharge from the Area 1
<br />Pit, runoff from the Refuse Pile, and minor amounts of underground mine discharge (also from the Area 1
<br />Pit). In general, because the Area 1 Pit is part of the mine-water collection and recycle system, discharge
<br />from the Area 1 Pit or underground mine discharge occurs rarely, if ever, since process water demand equals
<br />or exceeds normal flows to the Area 1 Pit. With construction and initiation of operations for Washplant II,
<br />process water withdrawals from the Area 1 Pit for the Washplant have been balanced with inputs to meet
<br />process demands and maintain a stable water level in the Pit (well below the maximum design water level).
<br />The Washplant II construction encroached on the Pond D emergency spillway, so the spillway was relocated
<br />to a location near the principal spillway riser on the Pond embankment. Spillway dimensions and
<br />configuration were preserved, and the new spillway location provides for better routing through the pond,
<br />increasing the distance between the eastern pond inlet and the spillway.
<br />TCC will survey Pond D per the previously outlined schedule. The same criteria will be used to determine if
<br />the pond requires cleaning. If so, the material will be removed and hauled to the refuse pile or pit for
<br />disposal. The pond is inspected during the regular CDPS sampling and the flume is checked to determine if
<br />it is functioning correctly. Any problems are noted and repairs made as-needed. Pond D is also an MSHA
<br />pond, subject to regular monthly inspections, except during the winter months. For the MSHA inspections,
<br />the outlet works and pond embankment are inspected, and any necessary repairs made in a timely basis. The
<br />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
<br />graded to blend with the surrounding terrain, and the area will be topsoiled and revegetated.
<br />Sedimentation Pond E controls runoff from a portion of the surface facilities, including the main coal
<br />stockpile area, prior to discharging to Foidel Creek. TCC will survey the pond per the previously outlined
<br />schedule. The same criteria will be used to determine if the pond requires cleaning.
<br />TR07-59 2.05 ?6.1 02/27/07
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