On November 17, WildEarth Guardians, the Sierra Club, the Environmental Integrity Project, and the Center for Biological Diversity filed a complaint in the U.S. District Court for the District of Columbia to force the Environmental Protection Agency to act on a June 2010 petition requesting regulation of emissions of methane and other pollutants from coal mines. Emissions of methane, particulate matter, volatile organic compounds, and nitrogen oxides are targeted in the petition for their negative impacts on air quality.