The 620-megawatt Vermont Yankee nuclear power plant disconnected from the regional power grid Monday after four decades of producing electricity, according to the company’s decommissioning website.
Vermont Yankee’s final day of operation came 16 months after parent company Entergy Corp. said the plant would close by the end of 2014. Entergy cited economic reasons for the shutdown, including high regulatory costs, increased competition from natural gas power plants, and disadvantageous market structures.
Vermont Yankee is along the Connecticut River in Vernon, VT, five miles north of the Massachusetts border. The plant, built in 1972 and purchased by Entergy in 2002, employed 625 workers when in August 2013 the company said the facility would close. A round of layoffs and retirements this month will slash the workforce, and further reductions will occur as workers prepare the plant for dormancy.
The reactor has been going through a “coast down period” since September, where its power level has been gradually reduced as fuel is spent, according to the company.
Under Entergy’s preferred decommissioning process, all spent nuclear fuel will at some point transfer to an on-site dry cask storage, and will stay there until the U.S. Dept. of Energy authorizes its removal. The reactor won’t end up dismantled until at least the 2040s.
Entergy estimates the cost of decommissioning at $1.24 billion. The estimate includes costs associated with terminating the Nuclear Regulatory Commission (NRC) operating license ($817 million), spent fuel management ($368 million) and site restoration ($57 million).
The wind-down of Vermont Yankee caps a drawn-out battle between plant owners and environmentalists who for decades fought the reactor’s right to operate. The plant has been the site of many anti-nuclear protests, including one in 2011 that drew 600 participants in the wake of the Fukushima Dai-ichi disaster in Japan.
The plant’s 40-year operating license was on schedule to expire in March 2012, but in March 2011 it ended up extended for another 20 years by the Nuclear Regulatory Commission. The Vermont legislature voted in February 2010 to block the license renewal, setting off a legal battle between Governor Peter Shumlin and Entergy; Entergy prevailed in January 2012 when a federal judge ruled the state did not have authority to close the plant.
In recent years, Vermont Yankee made headlines for a number of mechanical failures and problems, including 2007 and 2008 cooling tower collapses and tritium leaks reported in 2010 and 2011. Plant operators admitted in 2010 that they misled state officials while under oath about the existence of underground pipes carrying the tritium.