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Surface Facilities Area
<br />The sedimentation control structures associated with the portal area, as shown on Map 24, Surface Facilities, have
<br />been constructed in accordance with previously approved permits (CYCC Permit No. 79-177 and TCC Permit No. C-
<br />82-056). These structures include Ponds D, E, F, G, and the associated drainage collection ditches and discharge
<br />structures. An aerator may be utilized in Pond D to promote aerobic conditions, as appropriate. There is an existing
<br />powerline and power-box on the west side of the pond. Since the aerator is not essential to compliance with effluent
<br />limitations, its operation and use will be subject to site-specific considerations. The aerator and power supply will be
<br />removed prior to reclamation of the pond.
<br />All of the above referenced sedimentation control structures have been addressed under Rule 2.05.6, with the
<br />exception of surface drainage modifications associated with the new coal handling facilities. Drainage from these
<br />facilities will be channeled to Ponds D, E, F, and G as shown on Map 24, Surface Facilities. Diversion ditch and
<br />culvert designs are included in Exhibit 8, Sediment Control Plan.
<br />In order to provide for better drainage from the west ramp of the portal, the drainage system has been modified. The
<br />two culverts that carry water from the west ramp have been plugged, and the water is diverted to the Wadge sump.
<br />These culverts have been deleted from Map 24, but still exist in the field. Water will flow to a small sediment dam
<br />with a 4-inch overflow pipe draining to the Wadge Sump. This system will facilitate settling of sediment from the
<br />flow stream prior to discharge to the sump. From the sump, the water will be pumped through a 6-inch welded HDPE
<br />pipeline, discharging to the Area 1 Pit Storage Reservoir. The transfer pipeline, installed in 2008, crosses the edge of
<br />the previously disturbed coal stockpile and plant facilities areas, is buried approximately 5 feet deep, and will be
<br />plugged, cut-off below grade, and be buried in-place during site reclamation.
<br />Two water bodies, the Area 1 Pit MineWater Storage Reservoir and the Washplant I Thickener Overflow Sump,
<br />utilized in conjunction with ongoing mine water handling operations, have existed for years and were not previously
<br />identified or considered as "impoundments" under the regulatory defmition. As a result of changes in regulatory
<br />interpretation, however, the CDMG has determined that these existing water bodies fall under the broad defuution of
<br />"impoundments" and should be identified and regulated as such. Because they are existing water storage facilities
<br />and were not specifically designed or constructed as impoundments, the applicable requirements of Rule 4.05.9 are
<br />addressed in this context by the following descriptions and the referenced existing configuration drawings:
<br />Area 1 Pit Mine Water Storage Reservoir -The Area 1 Pit is a remnant surface mine pit adjacent to the Run-of--Mine
<br />Coal Stockpile), as shown on Map 24, Surface Facilities, and by Figure EX8v-1 in Exhibit 8V. This area was
<br />previously permitted, and is designated as a permanent disposal area for low-quality coaUcoal refuse, however, the
<br />western portion of the area is no longer utilized for this purpose, and has been converted to a mine water storage
<br />impoundment. Impoundment design, operation, maintenance, and reclamation information is provided in Exhibit 8v.
<br />The remnant pit area is a totally incised excavation, enclosed by undisturbed natural ground and backfilled surface
<br />mine spoils, with an estimated maximum water storage capacity of approximately 200 acre-feet. The western pit area
<br />is used for temporary storage of excess mine water, as part of the closed-loop mine dewatering and recycle system.
<br />Water inputs to the pit are limited to spoil spring discharge from the adjacent reclaimed spoils areas, excess
<br />dewatering flows from the mine dewatering systems (Portal and 0-Entry Borehole), and minor incident precipitation.
<br />An upgradient diversion ditch (Ditch D-3) intercepts any surface runoff from upgradient reclaimed surface mine areas
<br />and routes it around the Area 1 Pit to Pond D. While a small culvert outlet at the low point on the crest of the pit
<br />allows for minor discharge flow to Pond D if the water reaches this level, the temporary storage basin is normally
<br />managed to keep water levels well below the discharge pipe. A fixed pumping station is used to control water level,
<br />with discharge to a de-sander, located at an old well site, and then to Washplant I, or the mine water recycling system,
<br />or directly to Pond D for discharge to Foidel Creek. Management of the Area 1 Pit Mine Water Storage Reservoir
<br />involves regular inspection and maintenance of water levels and pumping systems, and reduction of water levels prior
<br />to spring discharge to provide additional water storage capacity for any minor increases in subsequent spoil spring
<br />discharge.
<br />MR08-231 2.05-79 11/20/08
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