Laserfiche WebLink
of this requirement, the source submitted an APEN for the generator for the main office building <br />server on February 15, 2013. <br />-Tioga Heater for ROM Processing Plant: It was noted during the inspection that there was a <br />diesel fired Tioga heater located near the ROM processing plant. The unit provides space <br />heating for the structures within the ROM processing area during winter months. The source <br />conservatively estimated in their January 11, 2013 correspondence that the Tioga Heater <br />consumes approximately 45,000 gallons of diesel fuel per year. This is based on a rate of 300 <br />gallons per day from November through March. In the response received February 14, 2013, <br />MCC provided emissions calculations (AP -42, Table 1.3-1, Boilers <100 MMBtu/hr, distillate oil) <br />which verified that at this consumption level, the unit is operating below APEN reporting <br />thresholds. Specifically, the unit's NOx emissions (the highest criteria pollutant emissions from <br />this unit), are only 0.45 tpy at a throughput of 45,000 gallons/yr. No APEN is required, and no <br />further action is required for this unit by the source. <br />-Used Oil Heater for Maintenance Shop: While reviewing the source's 2011 EPA Greenhouse <br />Gas Report, it was noted that the facility operates a used oil heater for their maintenance shop. <br />MCC was requested to provide fuel throughput for this heater in a' 111 Request Letter' dated <br />December 13, 2012 (extension granted on December 30, 2012). In their January 11, 2013 <br />response, MCC stated that they burn approximately 250 gallons of used oil in the heater per year. <br />This amount of fuel combustion would result in emissions far below the APEN reporting <br />thresholds. No APEN is required for this Point, and no further action is required by the source. <br />VOC Emissions Discussion: <br />The Division has recently become aware that certain coal mine operations may be significant <br />sources of uncontrolled VOC emissions which have been previously unreported. Almost all of the <br />hydrocarbon gas released during mining is methane (>98%), with small amounts of ethane also <br />present. Both methane and ethane are exempt from classification as VOCs for APEN/permitting <br />purposes (Ref: AQCC Regulation 3, Part A, § II.D.1.00). However, due to the extremely large <br />volume of gas released from coal mining operations, even a small percentage of non- <br />methane/ethane hydrocarbons (NMEHC = VOC) present in the gas stream can result in <br />significant VOC emissions. For example, MCC reported a total of 51,290 US tons (46,529.83 <br />metric tons) of methane released during 2011. Even at extremely low concentrations compared <br />to methane, VOC emissions above APEN and Permitting thresholds are extremely likely at such <br />high levels of methane release. <br />In 2009, Mountain Coal Company LLC — West Elk Mine conducted an extended gas analysis on <br />two of their E Seam MDWs as part of a draft environmental impact statement (see attached). <br />The samples were meant to be representative of emissions from a well at the beginning of its <br />'lifecycle' (i.e. high producing with 60.7% methane concentration) and a well at the end its <br />lifecycle (i.e. low producing with only 34.5% methane concentration). Using the values in these <br />extended gas analysis, the inspector calculated a ratio percentage of NMEHC:CH4 concentration <br />(CH4 = Methane). The high producing well had a NMEHC:CH4 ratio of 0.768% and the low <br />producing well had a ratio of 0.791 %. As each mine is required to track and record methane <br />emissions from all mine activities due to the greenhouse gas reporting rule, this value can thus be <br />multiplied by the total amount of methane reported in order to give an estimate of the NMEHC <br />emissions from each facility. This method was developed because of the limited data available <br />as to the total air flow from the facilities, and was also used to address variation in release <br />concentrations of methane from various points (variation which is accounted for in GHG methane <br />reporting records, which are available). Although these gas analyses were not conducted at all <br />points of the mine, they appear consistent with available literature which suggests that coal mine <br />gas includes a very small percentage of NMEHC. Furthermore, although methane gas <br />concentrations vary during gob drainage, it is reasonable to suggest that the extended gas <br />analysis results concerning overall NMEHC content in the gas samples remains relatively stable. <br />2012 Air Pollution Inspection <br />0510015-INSP-2012. docx Page 7 of 30 <br />