Jim Marsili, left, and Martin Garrigan, right, stand below the 580 MW coal-fired Cheswick Power Plant September 13, 2008 in Springdale, Pennsylvania. Marsili and Garrigan monitor the power plant to ensure it complies with noise and pollution guidelines they and local citizen groups claim the Reliant Energy owned company is violating. A 2004 emission inventory report showed the Cheswick plant is responsible for 80 percent of all sulfur dioxide emissions in western Pennsylvania's Allegheny County. Sulfur dioxide contributes to respiratory illnesses, particularly in the elderly and children, and aggravates heart and lung disease. Built in 1970, the Cheswick plant is now building a second smokestack of 550' to help reduce sulfur dioxide, mercury, hydrochloric acid and hydrogen fluoride emissions by 90 percent.