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

Home Browse Search

The tunnel also includes a 36-inch buried corrugated steel pipe escape tube extending from the tunnel approximately 50 feet to the south. One cubic yard of concrete was required at the point where the escape tube daylights. A 150-foot long 36-inch conveyor extends from within the tunnel to discharge directly into the stoker • trucks. Two cubic yards of concrete were required for a pad to support the conveyor structure. An MCC building was constructed neaz the escape tube exit. Dimensions of this building are approximately 15 x 15 feet, with a concrete floor requiring approximately 2 cubic yards of concrete. A retaining wall was constructed on the north side of the existing pile. The wall required 6 steel piles driven to a depth of 25 feet, with treated wood cribs placed between the piles to form the wall. On completion, this wall was approximately 50 feet long and up to 12 feet in height. Haulroad B-2 was widened by approximately 20 feet to allow for a loading area with room for traffic to pass trucks that are loading. The emergency spillway elevation of Pond E was staked and the toe of the fill does not extend past this line, to assure that no storage capacity is lost. Topsoil was stripped, salvaged, and stockpiled on the topsoil stockpile east of Pond E where the haulroad widening extended below the west of the pond embankment. No construction occurred within a buffer zone of 100 feet from Foidel Creek. Silt fences, hay bales, rock filters, or a combination of these control measures were used, as required, to prevent sediment from washing into Foide] Creek from the new fill material or road section. Reclamation associated with these additions will occur when the Washplant facility is dismantled. The concrete will be broken up and disposed of on-site. The steel associated with these additions will be either salvaged or disposed of on-site. New Coal Washplant (Washplant II - TR07-591 In 2007, TCC completed engineering/economic evaluations and determined that construction of a new washplant was justified to increase the amount of low-quality coal that could be converted to a saleable product, address fluctuations in ash content as mining extended into reserve boundary areas, and potentially increase mineable • reserves and extend mine life. The new washplant, Washplant II, has been designed to supplement the existing coal processing capacity of the existing washplant (Washplant I), with Washplant I being used to process low- quality coal, and Washplant II being used to wash and enhance the quality of the primary coal process stream from the ROM Coal Stockpile. The design for Washplant II focused on providing approximately 1,300 tph feed capacity, minimizing conveyor lengths and open coal stockpiling requirements, limiting potential air emission sources, providing for direct discharge of clean coal to the existing Overland Conveyor, and establishing a configuration that could be expanded in the future to add additional wash circuits, if needed. Washplant II is located to the southwest of the existing Washplant, between Washplant I and Sedimentation Pond D, adjacent to the Overland Conveyor, as shown on the Freshwater Systems and Surface Facilities Map, Map 24 (Sheet 1/3). In order to integrate the new Washplant R into the existing coal-handling system, construction modification of both new and existing equipment and facilities was required as follows: • Dismantle old Stacker Tube and associated conveyor structures • Modify the run-of--mine and low-quality coal handling systems to reduce the quantity of run-of--mine product diverted as low-quality coal, and to eliminate low-quality coal crashing and simplify flow (eliminate intermediate transfers) to Washplant I • Remove the primary and secondary screening equipment, crusher, and coal sampling system from the Crushing and Sampling buildings in the Belt-Out-Back (BOB) area • Modify chute-work in the Crusher and Sampling Buildings in the BOB area to allow duect pass-through of the coal product stream • Modify existing drainage structures, including the Sedimentation Pond D spillway(s) to accommodate the revised grading plans and drainage configuration • Complete site backfill, compaction, and grading activities to establish required facilities pad and yard areas • Complete required building and conveyor foundation work TR07-59 2.05-32 03/26/07