Central to the proposal, say Park Service and EPA experts, are four changes. They would:
•Substitute an annual average of emissions for the current "maximum" emissions that is measured over a few hours, up to a single day.
•Exclude from pollution estimates output from existing industrial emitters that have been granted variances.
•Switch from calculating emissions using the two most recent years of data to any time period "more representative" of normal operations.
•Grant discretion to state regulators to use whatever data and information in their judgment would be most reliable in calculating emissions.
The final period of public-comment on these changes closed earlier this month. The final rule is expected to take effect before the end of the year.
Several federal air-quality experts contacted by the Monitor say it is clear to them that EPA's planned changes would weaken the underpinnings of clean-air standards for Class 1 regions.
"We're talking about more pollution in national parks and wilderness, not less, because of this proposed change," says a federal air-quality expert, who asked not to be named because he was not permitted to speak to the press.
Lawmakers raise objections
Congress is concerned, too. In February, Rep. Henry Waxman (D) of Calif., chairman of the House Committee on Oversight and Government Reform, sent a letter expressing his concerns to EPA Administrator Stephen Johnson. In it, Congressman Waxman quotes an internal e-mail from Mr. Bunyak that compares the EPA's plan to average polluters' emissions over a year when evaluating air permit applications to "allowing a person to average all the variations in his driving speed over [an] entire year to see whether he is complying with the 55-mile-per-hour speed limit."