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2. In historical sections of the mine with sealed panels, underground gob methane drainage pipes <br />(sometimes referred to as inseam mine drainage) are used to provide fuel for surface heaters. During <br />periods of cold weather, this concentrated gas stream from sealed historical sections is used to fire <br />large burners located on intake air shafts for the mine ventilation systems. Shaft #1 and (each) Shaft <br />#2 intake ventilation system contains eight (8) burners for hot inlet air into the shaft, and have one (1) <br />burner used for deicing the system housing. MCC reported that the inseam drainage systems are <br />currently only utilized to provide fuel for ventilation burners, and this gas is not released uncontrolled <br />during other operations. Burner operations were reviewed during the 2012 inspection and determined <br />to not result in emissions above APEN-reporting thresholds. <br />3. For methane which has escaped into the mine ventilation air (i.e. was not removed by MVBs behind <br />the longwall or directly from the gob by inseam drainage systems), four large ventilation shafts <br />operate to provide adequate air replacement (Point 019). The Sylvester Gulch fan is equipped with a <br />Joy 1,500 hp motor. Shaft #1 has a TLT Babcock fan which is rated at 2,500 hp. Shaft #2 has two <br />TLT Babcock fans, each rated at 2,500 hp, but is restricted to operating only one (1) fan at any time. <br />Shaft #3 operates a Joy fan rated at 1,500 hp. The facility is restricted to operating with combined <br />ventilation air throughput of 3,000,000 cfin, and typically operates around 1,350,000 cfm. Methane <br />gas from these points, although usually at concentrations below 0.5%, constitutes the majority of the <br />methane emissions from the mine due to the high volume of air movement. <br />Emissions from ventilation fans also includes particulate matter in the form of coal dust and rock <br />dust. Although several of the intake shafts were observed at the time of the inspection, ventilation <br />shaft exhaust points for active areas of mine workings are located in the National Forest in the hills <br />above the mine, and were not observed during this inspection. The Sly Gulch fan was observed <br />operating during the inspection (inactive F Seam ventilation) with no visible emissions. <br />As will be discussed below in more detail, although most of the hydrocarbons released from the coal bed gas are <br />methane and ethane (exempt and not considered VOCs), a small percentage of the gas includes non-exempt VOCs <br />(i.e. propane, butane, pentane, hexanes, etc.). Because of the extremely large amount of methane released from <br />this facility, uncontrolled VOC emissions are also released at a level above the permitting threshold. See `VOC <br />Emissions Discussion' below for details. <br />Once removed from the underground mine via the 3,000 tph capacity conveyor, coal is transferred to ROM <br />stockpiles (Point 011) via three coal missiles. Bulldozers on the stockpiles move coal to respective areas within <br />the stockpile that signify different grades of coal, and also act to compact and turn the coal as needed to decrease <br />the risk of spontaneous ignition. There are several reclaim shoots below the stockpile which drop material onto a <br />conveyor in the reclaim tunnel to be transferred to the crushing and screening plant. At the plant, material is <br />crushed, screened, and classified down to the required size (Point 012), and residual rock is removed from the <br />process line and sent to a coal refuse area (Point 015). From the crushing and screening plant, coal travels by <br />conveyor to two large storage silos located near the highway. When a train is ready for loading, coal is reclaimed <br />from the silos and conveyed over Highway 133 to the train loadout (silos and loadout operations are covered <br />under Point 013). The coal flow within the crushing and screening plant is as follows: <br />Reclaimed material from the ROM stockpile passes through a roll crusher and two (2) parallel screens. <br />Small material is sent directly to the coal storage silos. Oversized material from the screens travels to the <br />rotary breaker. Small material from the rotary breaker is sent to the silos. Oversized material from the <br />rotary breaker is sent back to the roll crusher for reprocessing. There are water fog systems throughout the <br />processing plant to control particulate emissions on screens, crushers, and drop points into surge bins. <br />Similarly, water spray bars are used on belts to add moisture content to coal for processing. <br />2015 Inspection 1&17 <br />0510015-INSP-2015 Page 3 of 37 <br />