The Clean Air Act requires older power plants and industrial sources (built between 1962-1977) to install the "best available retrofit technology" (BART) if they cause or contribute to visibility impairment in any Class I area (national parks and wilderness areas)...
On March 10, 2005, EPA issued the Clean Air Interstate Rule (CAIR). CAIR will permanently cap emissions of sulfur dioxide (SO2) and nitrogen oxides (NOX) from electric-generating stations in the eastern United States...
In an extraordinary sequence, three tropical storms brought clean, pristine air to Great Smoky Mountains National Park, North Carolina/Tennessee, in September 2004...
The U.S. Environmental Protection Agency (EPA) is moving forward
with several air pollution control programs that will substantially reduce pollution
over the next 10-15 years...
The National Park Service has been following federal and state activities
related to the implementation of the new 8-hour ozone standard, including proposed rules by the
Environmental Protection Agency (EPA) on various alternatives for designating and classifying
nonattainment areas that are violating the ozone standard...
EPA is proposing to find that 29 eastern States and the District of Columbia contribute significantly
to nonattainment of the national ambient air quality standards for fine particles and/or 8-hour ozone in
downwind States...