Maine’s Board of Environmental Protection is expected tomorrow to decide whether FPLE, owner of the Wyman Station power plant in Yarmouth, can make re-quired reductions in the amount of nitrogen oxides the plant emits through a combination of on-site cuts and a trade for reductions elsewhere. It sounds complicated but has, or once had, most people concerned with the issue in favor of it.

Specifically, FPLE wants to cut 80 percent of the ozone-causing emissions at its plant through improvements in its facility. It wants to meet its obligation for the remaining 20 percent through a program called cap and trade, which lets a company with emissions below its regulated limit trade, essentially sell, the amount it is below the limit to another company. Done properly, cap and trade is a relatively inexpensive way for power plants to meet pollution laws, encourage new plants to be built cleaner than ever so that they will have something to trade and cut pollution on a regional rather than state level.

That’s why the Ozone Transport Region, made up of states from Maine to Virginia, favors trading these credits, and through the OTR, Maine has urged this program on other states. It is why the Natural Resources Council of Maine and other environmental organizations, now opposing the cap-and-trade proposal, favored the idea in 1998. They concluded then that cap and trade “will serve to ratchet down the total mass of emissions from the Ozone Transport Region’s power plants and large industrial boilers.”

Now environmental groups want FPLE to make all of its reductions in NOx entirely at its site, reasoning that this is the surest way of reducing pollutants. FPLE estimates that the cost of cutting the necessary 1,500 tons of NOx annually all on site at $50 million; making an 80 percent cut at the plant and trading credits for the final 20 percent would cost $10 million, plus the cost of credits at several hundred dollars a ton.

Ozone, a component of smog, doesn’t form the minute NOx leaves a smokestack. It takes three or four hours, depending on the amount of sunlight and other conditions, according to the Department of Environmental Protection. Because Maine’s location places it downwind of neighboring states with major power plants, the large majority of the smog here started somewhere else. Maine companies that reach agreements with those plants through cap and trade could have more impact on cleaning Maine’s air at a lower cost.

The results of this idea elsewhere, according to the group Environmental Defense, have been encouraging. For instance, the U.S. acid rain reduction program, which uses this process, has seen sulfur dioxide drop 30 percent below allowed levels over a decade, with power plants cutting more than 7 million tons of the pollutant. Environmental Defense concludes that cap and trade is “an affordable program that spurs innovation to cut pollution beyond what the law requires [and] is good for business and good for the planet.”

The BEP should conclude the same for Wyman Station and support this effective and affordable form of pollution control for Maine.