Laserfiche WebLink
combustion. Dust emission was controlled by watering. All precipitation runoff from the coal <br /> storage areas passed through sediment pond DP-1. <br /> A maximum of approximately 130,000 tons were stored at the D Portal Area. The temporary coal <br /> storage was reclaimed by front-end loaders and conveyed to the breaker by truck and/or temporary <br /> conveyors where it entered the normal processing stream. This area may be used periodically in <br /> the future to temporarily store up to 50,000 tons of coal and/or coal refuse. The location of the <br /> storage area is shown on Maps 26 and 27 as"Temporary Refuse Storage Area No.2". <br /> W.C.5 Preparation Plant The coal preparation plant is designed as a closed water circuit. A fine <br /> coal froth floatation circuit was added in early 1993 to increase recovery of fine coal and decrease <br /> the amount of refuse to be disposed. A thickener is incorporated into the circuit for removal of fine <br /> solids from the process water. Thickener underflow is further dewatered via filters. Depending <br /> upon the coal contents, this fine refuse is either combined with the coarse refuse for disposal or <br /> added to the clean coal circuit. The preparation plant building size is approximately 50 feet by 80 <br /> feet by 100 feet high. The thickener tank is 150 feet in diameter and 12 feet high. In 2019 a set of <br /> belt presses will be installed to treat the prep plant thickener slung. The belt presses will remove <br /> water from the slurry which will allow the solids to be disposed at the refuse pit. Design drawings for <br /> the upgrade can be found in Illustration 58. <br /> An emergency overflow pond is used to handle unscheduled overflows. Washdown water from the <br /> preparation plant and from the silos is collected and pumped to this pond. The emergency overflow, <br /> pond is shown as PP-1 on Map 15 and 26. <br /> Upon the cessation of mine operations, the breaker, preparation plant, thickener tank, sampling <br /> building, and machinery at the silos will be dismantled or demolished and removed and/or buried on <br /> site. The silos will be demolished and the debris buried on site. Foundations will be covered. <br /> Afterwards, the areas will be regraded and revegetated according to the procedures outlined in <br /> Section V, Reclamation Plan. <br /> IV.C.5.a Preparation Plant Bypass System <br /> A system to bypass washing of coal in the preparation plant was installed in the fall of 1995. This <br /> system is installed between the existing silos and the sampling building. This system will bypass <br /> some or all of the run-of-mine coal depending on the quality of coal being mined. The coal to be <br /> bypassed is transferred from the bottom of the existing silos by a belt conveyor to a transfer <br /> building, then to a crusher building by a second belt conveyor where it is crushed to 2" minus and <br /> then transferred by another belt conveyor to the existing sampling building. <br /> Minor Revision 175(5/2019) IV-9 <br />