Proposed anti-mercury rules may have minimal effect

AUGUSTA - The Regional Waste Systems trash incinerator in Portland would have to slash its mercury releases by at least 60 percent under new air pollution rules proposed Wednesday by state environmental regulators.

But the rules may have only a limited effect on mercury pollution in Maine.

Much of the mercury that has piled up in the state's rivers, lakes, fish and wildlife comes from sources outside Maine's borders. And the new rules would not apply to a trash plant in Auburn that also sends large amounts of the toxic metal into Maine's air.

Staff members at the Department of Environmental Protection said the Auburn plant is too small to regulate under federal guidelines for the rules. They said they would not go beyond those guidelines without support from the public.

''If the public demand is high,'' said Deborah Avalone-King of the DEP, ''the department may need to consider working with (Auburn) on an accelerated mercury reduction plan.''

The DEP will accept written public comments on the rules until Oct. 25. The rules would set limits for nine forms of air pollution from incinerators, including sulfur dioxide, carbon monoxide, lead, cadmium and dioxin.

Maine's mercury pollution problem was highlighted in a four-part investigative series published last week in the Maine Sunday Telegram and Portland Press Herald.

Mercury is a naturally occurring element that has built up to potentially dangerous levels in the environment because of industrial releases from coal-burning power plants, waste incinerators and some types of manufacturing.

The toxic metal rains out of the sky into lakes and rivers, where it is converted to a more toxic form that becomes increasingly concentrated as it moves up the food chain - from plankton and insects to amphibians, fish and humans.

Maine has four trash plants that discharge a total of 514 pounds of mercury into the air each year, or about 20 percent to 25 percent of the state's total industrial mercury air emissions.

The RWS plant, owned by 21 communities in Cumberland and York counties, burns up to 550 tons of trash a day and releases 301 pounds of mercury a year. Under the DEP rules, mercury emissions could not exceed 114 pounds a year.

RWS is studying technologies for removing mercury from the smokestack of its plant, located off outer Congress Street near the Maine Turnpike. The new pollution controls would have to be operating by December 2000 under guidelines set by the federal Environmental Protection Agency.

The state Board of Environmental Protection, an appointed panel that sets policy for the DEP, heard the proposed rules at a public hearing Wednesday. In comments to the board, DEP Commissioner Edward O. Sullivan said the rules were an important part of the department's plan for combating the mercury threat.

''Beyond reducing ozone pollution, mercury is probably the issue we're most concerned about,'' Sullivan said.

However, the impact of the DEP's trash incinerator rules may be limited.

DEP staff members said much of the mercury that falls into Maine waters comes from industrial sources as far away as the Midwest. State government is powerless to do anything about those long-distance emissions.

The federal Environmental Protection Agency has been studying mercury pollution since the early 1990s. But the EPA's study, which would lay the groundwork for more federal regulation, has been tied up by intensive political opposition.

The state's proposed incinerator rules also exempt the Mid-Maine Waste Action Coalition plant in Auburn, owned by a group of communities in the Lewiston-Auburn area.

The Auburn plant produces 193 pounds of mercury a year, second only to RWS. But it burns less than 250 tons of trash a day, below the minimum threshold set in federal guidelines for the incinerator rules.

By law, the DEP could set whatever standards it wants for the Auburn plant. But the Legislature has opposed efforts by the department to exceed federal minimums.

Without significant public comments on the need to regulate the Auburn plant, the DEP will have a tough time politically moving forward on its own.

At Wednesday's hearing, the only person who spoke on the proposed rules was David Dixon, a consulting engineer hired by the plants in Auburn, Biddeford and Orrington. Dixon said the rules were fair - but he opposed extending them to Auburn.

The plant would have to spend money on pollution controls to meet the DEP rules. But it could then face the ''economic hardship'' of more spending once the EPA adopts its own standards for smaller trash incinerators, he said.

EPA action on small plants is not expected for at least three years, Sullivan said.

He would not comment Wednesday on whether the DEP could accept that delay in reducing mercury emissions in Maine.

Most of the mercury released by incinerators comes from batteries, fluorescent lamps, thermostats and other consumer products burned in the plants.

The Maine Energy incinerator in Biddeford and the Penobscot Energy Recovery Co. in Orrington were designed to burn waste that has been sorted beforehand, removing metals such as batteries.

The plants also use a more sophisticated pollution control technology than the plants in Portland and Auburn, so their combined mercury emissions are only 20 pounds a year. Both plants already meet the proposed mercury limit.