2018-06-01_REVISION - C1980007 (3)

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Results of our initial evaluation of methane liberation from the West Elk Mine for the years 2011 through 2016 is expressed graphically in Figure 1 below. Figure 1: Graphic Representation of Publicly Available Methane Liberation Data for West Elk Mine Weekly Methane Liberated Volumes: 2011-2016 W C 80,000 70,000 60,000 v E 50,000 40,000 Gl 3 30,000 i Q. 20,000 a 10,000 ca 0 G! 2011 Weekly Drainage 2012 Weekly Drainage 2013 Weekly Drainage 2014 Weekly Drainage 2015 Weekly Drainage 2016 Weekly Drainage • • 2011 Weekly Ventilation • • 2012 Weekly Ventilation • • • • 2013 Weekly Ventilation • • 2014 Weekly Ventilation • • 2015 Weekly Ventilation • • 2016 Weekly Ventilation 2011 Total Liberated 2012 Total Liberated 2013 Total Liberated 2014 Total Liberated 2015 Total Liberated 2016 Total Liberated Methane liberated from the West Elk Mine was noticeably higher in 2011 and 2012 but rapidly decreased to levels seen in 2013 - 2016. For this reason, only data from 2013 — 2016 was used in our analysis, as the higher methane emissions may be related to mining conditions and production rates unique to those years. The total methane liberated during the period 2011 through 2016 was 3.25 billion cubic feet, 2.12 billion cubic feet, or 65 percent of total methane liberated was emitted to the atmosphere via the two ventilation exhaust shafts, and 1.13 billion cubic feet, or 35 percent of methane liberated, was drained via the GVBs. By employing a more aggressive drainage program, by more closely monitoring the GVBs and allowing the boreholes to produce for a longer period of time, it may be possible to capture a larger portion of the liberated methane which would otherwise be emitted by the ventilation system, thereby reducing the overall ratio of methane liberated via the exhaust shafts. Any acts to manage methane in the mine by increasing GVB production must be evaluated by management and make the safety of the miner paramount. In that regard, it is important to monitor the boreholes to ensure that there is no increased oxygen levels detected in the gob caused by increasing suction at the mine. Total methane liberated by the mine is equivalent to the carbon dioxide (CO2) emissions that would be generated from the consumption of 3.55 million barrels of oil. The volume of drained gas alone is sufficient to power an 8.5 MW power station, which would service approximately 5,525 homes. It would take 1.8 million acres of U.S. Forest lands one year to sequester the equivalent volume of greenhouse gases liberated as methane from the West Elk Mine between 2011 and 2016. 4