Laserfiche WebLink
operating below reporting thresholds as gas usage in these burners appears to be relatively low. <br />See 'Ventilation Shaft Burners' discussion section below for details. <br />Once removed from the underground mine via the 3,000 tph capacity conveyor, coal is <br />transferred to ROM stockpiles (Point 011) via three coal missiles. Bulldozers on the stockpiles <br />move coal to respective areas within the stockpile that signify different grades of coal, and also <br />act to compact and turn the coal as needed to decrease the risk of spontaneous ignition. There <br />are several reclaim shoots below the stockpile which drop material onto a conveyor in the reclaim <br />tunnel to be transferred to the screening/crushing plant. At the plant, material is crushed, <br />screened, and classified down to the required size (Point 012), and residual rock is removed from <br />the process line and sent to a coal refuse area (Point 015). From the crushing/screening plant, <br />coal travels by conveyor to two large storage silos located near the highway. When a train is <br />ready for loading, coal is reclaimed from the silos and conveyed over Highway 133 to the train <br />loadout (Silos and loadout operations covered under Point 013). <br />The eastern side of the current longwall panels mining the E Seam is too thin (consistently less <br />than 8') to mine without using a Coal Prep Plant (CPP), which was recently built and began <br />operation in 2010. When mining from thin areas of the seam where a higher percentage of total <br />material contains rock, this material is sent to the CPP, rather than the ROM stockpile. The CPP <br />(Point 020) is a separate processing plant in an enclosed building, which is used to separate rock <br />from coal product. This is accomplished by first crushing and screening the material similar to the <br />regular ROM processing plant. After the initial crushing and screening portions of the CPP, all <br />remaining processes are 'wet' and thus APEN exempt. Screened material is 'floated' across a <br />magnetite solution, and coal is skimmed off the surface while the heavier rock sinks. This is <br />possible because the magnetite raises the density of the water solution to a pre-set value such <br />that the coal will float. Following initial separation, the coal and refuse go through a series of <br />screens/separators used to wash and recover magnetite for re -use. Very little magnetite is lost in <br />the entire process. The separated coal is sent via conveyor to the appropriate stockpile near the <br />silos (Point 014), to later be reclaimed into the product for railcar loadout. Refuse rock material, <br />containing very little coal, is sent via conveyor to the coal refuse pile for burial (Point 015). <br />Prior to building their CPP, the facility would truck -haul marginal material to the nearby Bowie <br />prep plant (Point 014). Similarly, some material was previously hauled by truck to customers <br />from the ROM stockpile (Point 0016). Although still permitted for these activities, MCC has not <br />truck -hauled any coal since September 2010. Also permitted at the facility is an emergency <br />backup generator (Point 021) which powers the Shaft #2 fan. This generator was mandated by <br />MSHA to be installed, and will provide adequate ventilation air to miners if there is a loss of <br />power. To prevent the engine from stalling, a small generator is used to power the emergency <br />backup generator fan during startup. Similar other single backup emergency generators power <br />the elevator hoists to allow miners to exit the mine if there is a loss of power. <br />At the time of the inspection, the underground coal mine was operating but was not entered, as <br />this would require advanced safety training by Division personnel. Material was being dropped <br />down the coal missile into the ROM stockpile and bulldozing activities were also observed. <br />Although not operating at the time of the inspection, train loading at this facility was observed <br />during the two-day period spent in the area. No visible emissions were observed from any point <br />at this facility. <br />Unreported Emissions Discussion: <br />-Ventilation Shaft Burners: As stated above, the source uses large ventilation shaft intake air <br />burners during cold periods, in order to heat mine intake air and minimize ice buildup in <br />ventilation shafts. These burners utilize mine gas from the inseam gob drainage pipes, but <br />release combustion emissions which have not previously been reported to the Division. MCC <br />2012 Air Pollution Inspection <br />0510015-INSP-2012.docx Page 4 of 30 <br />