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human activities. Human activities have altered the chemical composition of the atmosphere through the buildup of greenhouse gases -primarily carbon dioxide, methane, and nitrous oxide. The heat-trapping property of these gases is undisputed although uncertainties exist about exactly how earth's climate responds to them. Even though methane is considered a greenhouse gas, emissions are not regulated. (Source: www.epa.~ov/Klobalwarminr). Coalbed methane is formed during coalification, which is the process that transforms plant material into coal. In 1999, U.S. coal mines liberated approximately 196 billion cubic feet of methane (www.epa.gov/coalbed). Coal mine methane emissions account for approximately 10 percent of total U.S. methane emissions (source: Inventory of U.S. Greenhouse Emissions and Sinks: 1990-2000). Globally, coal mines account for 8 percent of all methane emissions (Source: Intergovernmental Panel on Climate Change, 1996, www.epa.QOV/globalwarminR). The total amount of United Slates greenhouse gas emissions for 2000 is estimated to be 7,044 teragrams of carbon dioxide equivalents. Carbon dioxide comprised 83% of this amount, while methane comprised 10%. Methane emitted from coal mines comprised less than 1 % of the United States greenhouse gas emissions in 2000. (Source: Inventory of U.S. Greenhouse Emissions and Sinks: 1990-2000) Recent information received from MCC updates the methane data displayed in the EA in Section 2.2.2. Currently, methane is released from the West Elk Mine through the main ventilation system, a system of in mine horizontal drainage holes, and the existing MDWs. This additional information gives an indication of the methane release from the mine hi a typical month. Of the total methane release from the mine, it is estimated that [hat about 40% is contributed by [he main ventilation system, about 10% is contributed by the in-mine horizontal drainage system, and about 50% by the existing MDWs. The main ventilation system and the horizontal drainage system operate fairly consistently. Operation of the MD Ws fluctuates due to intermittent operating issues and varying numbers of MDWs in use at any given time. Operation of MDWs is modified to accommodate the mining progression. The MDWs are typically operated about 70% of the time. Measurements of the methane emitted from the main ventilation system indicates that in the month of April 2002, methane emissions ranged tietween 535,500 cubic feet per minute (cfm) and 897,300 cfm of methane. The in-mine horizontal drainage holes emitted an average of about 1.7 million cubic feet (mmcf) per day of methane for the month. There were 1 I MDWs in operation, and they emitted an average total of 9.7 mmcf of methane per day for the month. My decision will result in construction of up to 58 MDWs in the next 4 years. It is anticipated that between 6 and 14 MDWs would be in operation a[ any one time. The expected methane release from the MDWs is estimated to be between I.5 and 3.5 billion cubic feet (bcf) per year for 4 to 6 years, dependent on the variable gassiness of the strata. The methane emission from these MDWs would be in addition to the existing and ongoing methane emissions that have been occurring from the mine's main ventilation system and in-mine horizontal drainage system. MCC currently estimates that the mine emits an average of 19 mmcf of methane per day from all sources. This computes to 6.9 bcf of methane per year. With the operation of the MDWs from this decision, and assuming between 6 and 14 MDWs would be in use, the mine would emit between 4.9 and 6.9 bcf of methane per year. Thus, the West Elk Mine's percent of United States coal mine methane emissions would be about 3 percent, depending on fluctuations in the amount of methane emitted from coal mines nationally over the life of this project. Methane emitted from all US coal mines comprised less than 1% of the US greenhouse gas emissions in 2000. Therefore, the methane emitted from the West Elk Mine will comprise 3% of 1% of the U.S. greenhouse gas emissions (0.03%) The methane liberated from the West Elk Mine as a result of my decision will contribute 0.03% to United States Greenhouse gas emissions for a period of about 6 years. After reviewing the information available in the EA, [he project record, and references, I have concluded [ha[ my decision to contim~e to.allow [his amount of methane to be vented from MDWs into the atmosphere results in an insignificant contribution to the total amount of greenhouse gases emitted in the US. This insignificant contribution to greenhouse gas emissions does not require environmental documentation in an EIS.. Final Version 5/31/02 Page 20