2012-11-21_PERMIT FILE - C1982056A (3)

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acres to be redisturbed is approximately $360K), along with the calculated bond coverage for a 50 acre area (approximately $380K), addresses bonding for the initial area of disturbance, as shown on Drawing C -102 in Exhibit 26C. This initial bonded area includes redisturbance of the eastern side of the existing RDA (approximately 40 acres), the initial CRDA bonded disturbance area (approximately 30.3 acres), haulroad disturbance (approximately 2.4 acres), stockpile and ditch disturbance (approximately 9.4 acres), stockpile access corridors (0.4 acres), and a bonded buffer of approximately 7.5 acres to address any minor unplanned disturbances. With a total facility life of approximately 14 to 20 years, it is anticipated that the remaining 50 acres of the total CRDA expansion area of 140 acres will be bonded in two future bond increments of approximately 20 -30 acres each (each increment will be approximately $150K - $230K, depending on size). It is anticipated that Bond Increment I will occur 3 -5 years in the future, and that Bond Increment II will occur 7 -10 years in the future. Consistent with the constraints inherent in a cumulative bonding approach, TCC will clearly delineate bonded areas, will limit disturbance to those areas, and will work with the CDRMS to determine and maintain adequate bond coverage for all activities. Concerning the Fish Creek Tipple, no excess spoil or underground development waste will be generated in connection with the operation. Thus, the requirements of this section and Rule 4.09 are not applicable. (9) Return of Coal Mine Waste to Abandoned Workings (a) Each plan shall describe the design, operation and maintenance of any proposed coal processing mine waste disposal facility, including flow diagrams and any other necessary drawings and maps which must meet the standards of 2. 10, for the approval of both the Division and the Mine Safety and Health Administration in accordance with 4.11.3. (b) Each plan shall describe the source and quality of waste to be stored, area to be backfilled, percent of the mine void to be filled, method of constructing underground retaining walls, influence of the backfilling operation on active underground mine operations, surface area to be supported by the backfill, and the anticipated occurrence of surface effects followina backfilline. (c) The applicant shall describe the source of hydraulic transport medium, method of dewatering the placed backfill, retainment of water underground, treatment of water if released to surface streams, and the effect on the hydrologic re i (d) The plan shall describe each permanent monitoring well to be located in the backfilled area, the stratum underlvina the mined coal, and gradient from the backfilled area. (e) The requirements of 2.05.3 shall also apply to pneumatic backfilling operations, exceMt where the operations are exempted by the Division from requirements specifying hydrologic monitoring. TCC returns the thickener underflow generated at both Washplants I and II to the abandoned and sealed underground mine workings. When Washplant I initially began operations, the thickener underflow was partially dewatered using a filter- press, and this material was then combined with the coarse refuse and hauled to the Refuse Pile for placement. Due to handling and placement problems, TC modified the fine refuse handling method, and began pumping the thickener underflow into the abandoned mine workings in the Southwest Mining District (SWMD), as opposed to mixing it with the coarse refuse for placement on the Refuse Pile. With both Washplants I and Il operating, the thickener underflow is typically a 15 to 25 percent solids, 300 to 550 gpm slurry mixture of rock and coal fines (28 mesh x 0). Exhibit 9C, Underflow Chemical Characterization, provides data on selected chemical constituents found in the thickener underflow. The water quality of the slurry is consistent with that of typical spoils water generated at the adjacent CYCC surface mine. The slurry mixture has been piped to the sealed mine workings in the SWMD, where the fines settle -out, and the decant water flows to a sump and is recycled back to the washplants. At the full coal fines refuse discharge rate, approximately 1.6MM ft3 of coal fines storage is required on an annual basis. The SWMD has approximately 110MM ft3 of coal fines storage capacity remaining (approximately 70 -years capacity). In anticipation of possible future mining of the underlying Wolf Creek Coal Seam, TC is shifting underground coal fines slurry placement to sealed mine workings TR 12 -80 2.05 -97.6 09/04/12