WISCASSET – Voters in the town that was home to the Maine Yankee atomic plant will have a say Nov. 6 on a proposal for a new, $1.5 billion power plant on the site of the decommissioned nuclear reactor.

If voters in the midcoast town approve the idea, developers of Twin River Energy Center say they’ll move forward with studies and designs, with hopes of breaking ground in 2009 for the 700-megawatt coal gasification plant.

The question before Wiscasset voters seeks approval of a zoning change to allow a 230-foot-tall building at the plant site. Even if the voters approve, the project would also face a review by state regulatory agencies.

Supporters of the proposed plant say it will generate clean energy, jobs and tax revenue.

Scott Houldin, who manages the project for the Connecticut-based National RE/sources, said the plant would be nothing like the traditional coal-fired plants that spew pollutants into the air and give coal its bad name.

“We don’t burn coal. We create gas from the coal and then that gas is cleaned,” Houldin said. “Environmentally speaking, we’re actually going to lower the air emissions in the state of Maine.”

The site was chosen because power lines and railroads that served Maine Yankee are already there. Supporters say it would replace the industrial tax base that was lost when Maine Yankee closed in 1996.

Environmentalists take issue with those claims. While some pollutants would be removed, 5 million tons of carbon dioxide, a global warming gas, could be released by the plant each year, said Steve Hinchman, staff attorney for the Conservation Law Foundation in Brunswick.

Maine’s six largest existing power plants, which burn natural gas, wood and oil, now pump about 6 million tons of carbon dioxide a year into the atmosphere.

The proposed plant “would roll back all the good work Maine has done over the past five years to fight climate change,” Hinchman said. “There’s no such thing as clean coal. Coal is not clean.”

Coal for the plant would be shipped up the East Coast by barge. The coal would be pulverized and superheated under high pressure to create a synthetic gas, a cleaner, more efficient fuel than the coal it came from. Biomass or wood would also be fed into the gasifier as a supplemental fuel.