MONTPELIER, Vt. -- The owners of Vermont's only nuclear power plant filed suit Monday to stop the state from closing the plant, which recently won a 20-year license extension from federal regulators but still needs a state permit.
Vermont is the only state in the country with a law saying both houses of its legislature have to give their approval before regulators can issue a state license for the nuclear plant to continue operating.
In a complaint filed in U.S. District Court in Burlington, New Orleans-based Entergy contends that the U.S. Supreme Court has found that states have no authority over nuclear plant licensing. It also says Vermont might be interfering with federal authority to regulate the wholesale power market.
Built in 1972, the Vermont Yankee power plant has been plagued by leaks of radioactive tritium and strained relations with Vermont authorities.
Last year, the state Senate voted 26-4 to block the plant from operating past March 2012, when its state permit expires.
Gov. Peter Shumlin, a staunch opponent of the plant, didn't immediately comment on the lawsuit. He called an afternoon news conference in the state capital.
Located on the banks of the Connecticut River in Vernon, within sight of New Hampshire and about three miles from the Massachusetts line, the plant is a General Electric Mark 1 boiling water reactor, as are the Fukushima reactors damaged in last month's tsunami in Japan.
Entergy bought it from a group of New England utilities in 2002.
In January 2010, Vermont Yankee announced that test wells had turned up evidence that radioactive tritium had leaked from underground pipes at the plant into surrounding soil and groundwater. Within days, it was revealed that plant executives had misled state lawmakers and regulators – the latter under oath – by saying the plant did not have the type of underground pipes that carried radioactive substances.
But the U.S. Nuclear Regulatory Commission granted it a 20-year license extension last month.
Entergy's suit sets up a legal battle over whether the state or federal government has the final say in nuclear plant licensing.