PORTLAND – The owner of Wyman Station in Yarmouth has come to terms with an environmental group on a plan to cut air pollution at Maine’s largest and dirtiest power plant.

FPL Group has backed away from its controversial emissions trading program and embraced a plan that would require Wyman to reduce emissions on site, but do so by use of a more cost-effective technology.

FPL and the Natural Resources Council of Maine worked for several weeks with the Department of Environmental Protection, which came up with the new air-quality plan on which both parties agree.

After the state’s Board of Environmental Protection takes public comment on the plan, it will schedule a vote on whether to approve it.

Because prevailing winds carry Wyman’s emissions Down East, the new regulation would mean cleaner air for Maine not only around the plant but as far away as Acadia National Park, Jim Brooks, director of the DEP’s Bureau of Air Quality, said Wednesday.

The new plan calls for the oil-burning plant on Cousins Island to install new pollution-control technology that will reduce smog-creating nitrogen oxides by 25 percent to 40 percent by the time the plan is implemented fully in 2005.

Passage of the plan “would be a victory for Maine’s environment,” said Pete Didisheim, advocacy director of the Natural Resources Council of Maine. He said the reduction of 800 to 1,200 tons of nitrous oxides annually would be equal to removing 27,000 to 40,000 cars from the road.

The controversy over emissions from Wyman, which is Maine’s largest single source of nitrogen oxides, has been ongoing since FPL bought the plant about two years ago.

FPL had proposed emissions trading as a way to reduce what it estimated would be the $50 million cost for it to install anti-pollution technology on each of its four generators to reduce emissions. It wanted to spend just $10 million on pollution controls at the plant and rely on emissions trading to satisfy Maine’s air-quality standards fully.