Action on greenhouse gases: it's about time

The Environmental Protection Agency is finally taking steps to limit the release of greenhouse gases in the United States. Large emitters will have to demonstrate that they're using the latest technology to reduce their emissions just as they already have to for pollutants like sulfur dioxide.

“We are not going to continue with business as usual,” Lisa P. Jackson, the E.P.A. administrator, said Wednesday in a conference call with reporters. “We have the tools and the technology to move forward today, and we are using them.”

The proposed rules, which could take effect as early as 2011, would place the greatest burden on 400 power plants, new ones and those undergoing substantial renovation, by requiring them to prove that they have applied the best available technology to reduce emissions or face penalties.

Ms. Jackson described the proposal as a common-sense rule tailored to apply to only the largest facilities — those that emit at least 25,000 tons of carbon dioxide a year — which are responsible for nearly 70 percent of greenhouse gas emissions in the United States.

The rule would not, as critics contend, cover “every cow and Dunkin’ Donuts,” Ms. Jackson said.