Late yesterday afternoon, the U.S. Environmental Protection Agency (EPA) announced a court settlement requiring it to adopt clean air standards that protect revered national parks and wilderness areas from air pollution-related ecosystem damage. Under the agreement between EPA and Environmental Defense, the Agency must address standards for limiting nitrogen oxides air pollution affecting national parks and wilderness areas including Acadia, Grand Canyon, Great Smoky Mountains, Rocky Mountain, and Shenandoah.

The settlement was prompted by a lawsuit filed by Earthjustice on behalf of Environmental Defense, aimed at ending EPA’s 13-year delay in strengthening clean air standards to protect ecosystems in some of the nation’s most prized national parks. EPA must propose a rule to address nitrogen oxide pollution by September 30, 2004, and issue a final rule by September 30, 2005.

“This is a case of ‘better late than never,” said Earthjustice attorney Jennifer Kefer, who represented Environmental Defense in the lawsuit and settlement negotiations. “If adequate nitrogen oxide limits had been put in place when the court first ordered it 13-years ago, we’d have far fewer high pollution days harming our parks and wilderness areas. Hopefully, the new rules EPA must now adopt will prevent any further decline in air quality.”

“This settlement will help protect some of America’s most inspiring places, from the Grand Canyon in the West to the Great Smokies in the East,” said Vickie Patton, a senior attorney at Environmental Defense. “Air pollution in our national parks is bad for visitors’ health, acidifies lakes and streams, and degrades scenic vistas. Today’s settlement will help protect our national parks and the Americans that visit them.”

In a previous lawsuit, Environmental Defense challenged significant deficiencies in EPA’s existing limits for nitrogen oxides (NOx) air pollution. In 1990, the DC Circuit court agreed that EPA had failed to comply with the law, and instructed EPA to reconsider its rules, but the agency still had not done so, 13 years after the ruling.

Nitrogen oxides contribute to numerous environmental and ecosystem effects. According to the National Park Service, ozone (smog) pollution is worsening in our national parks, from Yellowstone in the north to the Grand Canyon in the south. Vegetation damage caused by high ozone pollution is also changing ecosystems in parks, including Shenandoah, Yosemite and Great Smoky Mountains. The plant species impacted by ozone include quaking aspen, red maple, Jeffrey pine, paper birch, eastern white pine, American sycamore, and flowering dogwood trees. At the same time, nitrogen deposition due to NOx is acidifying lakes and streams in the East, and altering high altitude ecosystems in the Rockies. The National Park Service has also found that air pollution currently impairs visibility to some degree in every national park, with the average visual range in most of the Western U.S. now about one-half to two-thirds of what it would be without manmade air pollution. In most of the East, the average visual range is about one-fifth of what it would be under natural conditions.

A public comment period and court approval is required before the settlement becomes final.