A leaked document from the Environmental Protection Agency suggests that the agency is considering a significant change in air-pollution rules. It would give chemical factories, refineries and manufacturing plants new leeway to increase emissions of pollutants that cause cancer and birth defects.

John Walke, who heads the clean-air program for the environmental group Natural Resources Defense Council, says he received the document from sources at the EPA who wanted the public to become aware of this "backward step."

Currently, any factory that emits more than 25 tons of toxic chemicals into the air each year must reduce its pollution as much as it feasibly can. Walke says the draft proposal would give a break to companies that own those plants. After they clean up, their only requirement would be to keep their pollution below 25 tons a year.

"Take an oil refinery that 10 years ago polluted 100 tons of toxic air pollution," Walke says. "Due to the Clean Air Act, that refinery today will emit only five tons of toxic air pollution. Under this EPA proposal, that refinery can increase it's toxic pollution from five tons to 25 tons."

But Lorraine Gershman of the American Chemistry Council says there are no incentives to increase emissions under the new rules.

Gershman says her industry has been pushing EPA to make the changes described in the draft rule. Under the current rules, even after the factory cleans up, it's still considered a major polluter and is required to keep monitoring its pollution and reporting what it learns to the government. Under the draft proposal, these requirements would disappear.

"We believe it's EPA recognizing a lot of these major sources have made in reducing their emissions and realizing that there should be some sort of benefit of that, and that is reducing the administrative burdens," Gershman says.

Lobbyist Scott Segal, who represents refineries, says the proposal will give big polluters the incentive to reduce pollution below that 25-ton-a-year cap.

But EPA officials charged with running the air toxics programs outside of Washington apparently disagree. In December, the regional officials sent a letter to EPA headquarters warning that the draft rule would be "detrimental to the environment and undermine the intent of the program."

The letter criticizes EPA's draft rule for failing to analyze how many companies might be encouraged to cut pollution and how many might relax their pollution controls because they're already under the threshold.

In the draft rule, the EPA asserts that plants will not use the rule to increase pollution because they'll want to "avoid negative publicity and maintain their appearance as responsible businesses."

But EPA's regional air toxic chiefs in their letter call that statement unfounded and overly optimistic.

EPA spokesperson Lisa Lybbert released a statement saying that "commenting on the draft at this point in the process is like asking us how a cake tastes when we haven't even put the batter in the oven."

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