SO2

May 1, 2014, 5am PDT
In a huge and perhaps unexpected win for the EPA, the Supreme Court on April 29 reversed an appellate court panel ruling that had rejected their attempt to regulate interstate air pollution caused by about 1,000 coal-fired power plants in 28 states.
The Wall Street Journal - Politics and Policy
August 25, 2012, 9am PDT
For the second time, a court has thrown out EPA efforts to address pollution from power plants in 'clean-air' states that cause pollution downwind. This time, the Cross-State Air Pollution Rule was the victim.
The New York Times - Environment