2008-01-11_PERMIT FILE - C1982056A (2)

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The Coal Washplant structures aze of steel-frame constmction with steel siding and roofs, and typical constmction techniques were used to erect these structures, including use of a crane or boom track to set stmctures, and the use of metal fabricating equipment for wnstmction. The approximate dimensions of the structures are as follows: Washplant Building - 48 x 54 x 76 feet Thickener Tank - 35-foot diameter x 18 feet deep Refuse Bin - 2 x 54 x 76 feet Transformer Pad Low-quality coal is transported by a front-end loader from the Low-Quality Coal Stockpile to the Plant Feed Grizzly. Coarse material, consisting primarily of 4-inch plus waste rock, is diverted from the grizzly to a chute and temporary storage azea on the north side of the Washplant. This material is periodically recovered, loaded into haul tracks and transported to the approved coal refuse pile for placement and disposal along with the coal refuse generated from the washing process. From the Plant Feed Grizzly, the low-quality coal material is conveyed to the plant for processing. A reclaim tunnel, feed conveyor, and hopper transfer the low-quality coal into the coal Washplant. The plant is designed to process up to approximately 300 tons per hour using a heavy media (magnetite) to separate coal from waste rock inclusions. Two magnetite storage bins (50 and 100 tons) aze located adjacent to the plant. A Thickener Tank is constmcted adjacent to the plant. An emergency overflow sump adjacent to the plant provides overflow storage capacity in the event a power outage occurs and the Thickener has to be partially or fully drained. The overflow sump is sized to hold the entire contents of the Thickener while maintaining one-foot of freeboazd. In the event the Thickener has to be dumped, the material will be pumped back into the system or to Pond D. After the low-quality coal is processed, clean coal is transferred directly onto the Overland Conveyor or transferred via wnveyor to a Clean Coal Stockpile adjacent to the Washplant. A front-end loader can be used to transfer the stockpiled clean coal to a feed bin on the Overland Conveyor. The clean coal is then transferred via the Overland Conveyor to the Tipple. The processed clean coal may also be utilized in the production of stoker coal, with the stoker coal stockpile located on the west side of the Washplant. The circulaz Stoker Coal Stockpile azea is located on the west side of the Washplant and encompasses an approximately 120-foot diameter azea centered below the stacking conveyor. The Clean Coal Stockpile is approximately rectangular in shape and encompasses the westemmost portion of the ROM Coal Stockpile azea as depicted on Map 24. This area is approximately 200 x 250 feet. Up to three feet of coarse rock material (coarse refuse from the grizzly) was laid down as base course in these azeas. In total, 1,260 yazds are spread under the stoker pile and 5,560 yazds aze spread under the clean coal pile. This material will be excavated and relocated to the approved refuse disposal area during reclamation of the Washplant facilities. The refuse material generated during the washing process is transferred via a conveyor belt to a Refuse Bin. Refuse is transferred from the bin to haul tracks which transport the refuse to the designed Coal Refuse Disposal Facility. In order to reduce the amount of refuse hauled to the refuse pile, TCC pumps the thickener underflow (refuse fines mixed with water) directly into abandoned and sealed underground workings. The material is pumped into the mined-out longwall panels in the Eastern Mining District. The underflow is pumped via a 4-inch line to an existing fresh water borehole into the mine. The bottom of the borehole is plumbed into a pipeline terminating at a dischazge point located behind the seals in the EMD. The process is described in greater detail under Rule 2.05.3(9). On completion and commissioning of the Coal Washplant, TCC temporarily stockpiled material generated during the start-up period to allow sampling and evaluation of the quality of the reject material being produced and the percent recovery of coal from the feed coal material, in order to better understand the functioning of the plant. This material was stockpiled at a site on the existing Low-Quality Coal Stockpile. The material was tested to determine if the plant was producing the quality of washed coal projected in the design, and to determine if the physical characteristics of the refuse material produced were consistent with the parameters used in designing the Refuse Pile TR07-59 2.05-30 02/27/07