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The Division has recently become aware that certain coal mine operations may be <br />significant sources of uncontrolled VOC emissions which have been previously <br />unreported. Almost all of the hydrocarbon gas released during mining is methane <br />(>98%), with small amounts of ethane also present. Both methane and ethane are exempt <br />from classification as VOCs for APEN [Air Pollution Emission Notice]/permitting <br />purposes (Ref: AQCC [Air Quality Control Commission] Regulation 3, Part A, § <br />II.D. Loo). However, due to the extremely large volume of gas released from coal mining <br />operations, even a small percentage of non-methane/ethane hydrocarbons (NMEHC = <br />VOC) present in the gas stream can result in significant VOC emissions. For example, <br />MCC reported a total of 51,290 US tons (46,529.83 metric tons) of methane released <br />during 2011. Even at extremely low concentrations compared to methane, VOC <br />emissions above APEN and Permitting thresholds are extremely likely at such high levels <br />of methane release. <br />In 2009, Mountain Coal Company LLC — West Elk Mine conducted an extended gas <br />analysis on two of their E Seam MDWs as part of a draft environmental impact statement <br />(see attached). The samples were meant to be representative of emissions from a well at <br />the beginning of its `lifecycle' (i.e. high producing with 60.7% methane concentration) <br />and a well at the end its lifecycle (i.e. low producing with only 34.5% methane <br />concentration). Using the values in these extended gas analysis, the inspector calculated <br />a ratio percentage of NMEHC:CH4 concentration (CH4 = Methane). The high producing <br />well had a NMEHC:CH4 ratio of 0.768% and the low producing well had a ratio of <br />0.791%. As each mine is required to track and record methane emissions from all mine <br />activities due to the greenhouse gas reporting rule, this value can thus be multiplied by <br />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 <br />available as to the total air flow from the facilities, and was also used to address variation <br />in release concentrations of methane from various points (variation which is accounted <br />for in GHG methane reporting records, which are available). Although these gas <br />analyses were not conducted at all points of the mine, they appear consistent with <br />available literature which suggests that coal mine gas includes a very small percentage of <br />NMEHC. Furthermore, although methane gas concentrations vary during gob drainage, <br />it is reasonable to suggest that the extended gas analysis results concerning overall <br />NMEHC content in the gas samples remains relatively stable. This is reinforced as the <br />two extended gas analysis performed on both the high producing well and low producing <br />well had similar NMEHC:CH4 ratio percentages. <br />Therefore, using the total methane emissions data in the greenhouse gas reports, in <br />conjunction with the 2009 extended gas analysis which were performed on two of <br />the MDWs, the Division asserts that MCC has been operating with NMEHC/VOC <br />emissions far above the APEN-required threshold of 2 tpy [tons per year] from <br />individual points (Ref: AQCC Regulation 3, Part A, Section II.B.3.a.), and the <br />permit -required threshold of 5 tons per year from all APEN-required sources at the <br />facility (Ref: AQCC Regulation 3, Part B, Section II.D.3.a.). As stated above, MCC <br />reported with their recent greenhouse gas report that the facility emitted 51,290 tons of <br />methane in 2011. Multiplying this value by the 0.768% and 0.791% NMEHC:CH4 ratio <br />10 <br />