It's hard to believe, rocking on the front porch of the Roosevelt Lodge, looking out on a magnificent mountain range, that the nation's oldest national park has an air-pollution problem -- regional haze.

Could a place such as this, filled with wild lupines and sticky geraniums, open fields of sagebrush and a porcelain-blue sky, possibly have air quality so poor that it would damage the visual feast of 2.2 million acres of forest, waterfalls and steamy geyser shows?

It does, say regulators at the Environmental Protection Agency. The agency, after years of study and controversy over the issue, came out with a final rule recently that will attempt over the next 65 years to return Yellowstone and 155 other national parks and wilderness areas to their former natural beauty and pristine status. In other words, on a clear day, visitors to these areas should be able to see forever.

"It's the difference between seeing 60 miles or six miles," said William Becker, executive director of the State and Territorial Air Pollution Program Administrators.

That's not the case at many national parks right now. A top EPA official who worked on the rule said that on a good day at Yellowstone there may seem to be no visual impairment, but, on a bad one, vistas can be reduced from 127 miles to 72 miles. At the Grand Canyon, views can be reduced by as much as 50 percent.

In Pinkham Notch, N.H., at the Appalachian Mountain Club visitors center, Bruce Hill, who is head of research for AMC, has his office in the shadow of Mount Washington. From his vantage point, and from checking air-quality monitors, he can attest that there are days -- such as last Saturday -- that the air is as polluted there as in any major urban area.

"On a clear day, you can see 130 miles to the Adirondacks. On Saturday, we exceeded the federal health standard for ozone and smog. And we're one of the cleaner places in the Appalachians," Hill said. The peak of Mount Washington is 6,288 feet above sea level.

Reducing haze to natural background levels means returning the picturescape to a condition where no human-caused pollution impairs visibility, according to the Clean Air Act.

Federal regulators said sulfates, nitrates, organic carbon, diesel emissions and smoke know no boundaries. These pollutants create a general haze that can move over large geographical areas. Automobiles, power plants and large industrial boilers are contributing factors.

The EPA's rule is in response to a mandate issued by Congress 20 years ago to establish national goals for visibility in these special areas. After two proposals, and discussions with hundreds of interest groups and businesses, what the agency came up with is a highly technical haze abatement plan that in its mind-numbing complexity is the antithesis of the simple natural beauty that visitors see at Yellowstone.

Under the rule, the states will have to participate in planning, analysis and emission-control programs. Some will be expected to cut emissions even more than they have already through programs such as vehicle emission reductions, while others may choose to trade pollution credits among themselves. Some will have to make sure that older industrial sites such as smelters, refineries and electric utilities are using the best available technology to clean up pollution.

The aim of the rule is to improve visibility on the haziest days and ensure that no degradation occurs on the clearest days. The agency will use "deciviews," or an atmospheric haze index, to track changes in visibility, and it will measure emission fluctuations reported by the states as well.

EPA has asked all states -- regardless of whether they have a park within their borders -- to develop plans for how they will cut pollution over the next 60 years. The first plans are due in 2003.

"The idea here is to have a long-term strategy to return these pristine areas to natural visibility," said a top EPA official, who asked not to be named. "We hope to have significant progress in less than 60 years."

But even before the first step toward improvement is made, 12 large industrial groups representing railroads, coal, manufacturers and utilities have petitioned the EPA to stop the rule. They claim the regional haze rules cannot go forward because they are tied to other pollution-abatement rules that recently were struck down in court.

"It's arbitrary to go forward now," said Paul Seby, a lawyer in Denver who filed the petition.

As for the cost of the rule, it's a pretty penny. The EPA estimates that it's somewhere between $1 billion and $4 billion, with benefits that could be worth as much as $10.8 billion annually.

But who's counting? Certainly no one on the front porch of the Roosevelt Lodge.

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