"EPA Sees Decline in Toxic Air Releases"
"The U.S. Environmental Protection Agency said Wednesday that total toxic air releases in 2011 declined 8 percent from 2010. In the mid-Atlantic region, which includes Pennsylvania and Delaware, the agency recorded a decline of 13.8 percent or 32.5 million pounds. Among the hazardous air pollutants showing declines were hydrochloric acid and mercury, which EPA attributed to improved pollution control technologies at coal-fired power plants and a shift to other fuel sources."