The latest Environmental Protection Agency (searchstudy says President Bush's Clear Skies Initiative would mean clean and healthy air in almost every American city.

"This problem that has looked really almost unsolvable for years and years is solvable," John Holmstead, EPA Assistant Administrator at the Office of Air and Radiation (search), told Fox News.

The study, released last week, says if Congress approves Clear Skies (search), the United States would experience less smog, less acid rain, and better visibility at national parks.

"If you reduce diesel emissions, and if you substantially reduce power plant emissions, the combination of those two things will provide healthy air quality to virtually everybody in the United States," Holmstead said.

The report says that 65 million people around the country were affected by unhealthy air particles that exceeded health standards in 2001. Under Clear Skies, the report concludes that the problem in the eastern United States would be virtually eliminated by the year 2020.

But the report's statistics don't impress environmental groups.

"The new numbers out ... from EPA are really old wine in a new bottle," said John Coifman of the Natural Resources Defense Council (search).

Coifman said the president's plan will actually roll back air quality protections already in place. The NRDC is running a new television ad that makes a comparison with terrorism to criticize the Bush pollution plan.

"They're not weapons, but they cause mass destruction," the ad says.

The president's plan faces an uphill battle in Congress. Sen. Tom Carper, D-Del., said his version -- the Clean Air Planning Act (search-- would cost more, but would save more lives.

"We can actually reduce the number of premature deaths from people who are breathing bad things in our air by over 5,000 people per year by 2020," Carper said. "At the same time, the cost to us as consumers for our monthly electricity bill is only a couple of bucks."

Carper said the EPA has a study that backs him up, but officials refuse to give it to him.

"We're trying to make all these decisions based on good science, and it would sure be helpful to have the benefit of their expert analysis," he said.

Holmstead denies his agency is holding anything back.

"We have provided Sen. Carper with all of the data and analysis that he's asked for," Holmstead said.

Another big problem for environmentalists: the Clear Skies Initiative does not address carbon dioxide emissions, which have been linked to global warming. Holmstead said environmentalists are not dealing in economic reality.

"We could shut down all the power plants in the United States, and we would get greater environmental benefits," he said.

Holmstead said the president is determined to get an air pollution bill passed soon. But unless it generates more enthusiasm in Congress, the forecast for his Clear Skies Initiative remains cloudy.

Fox News' Maggie Dore contributed to this report.