More than a dozen nuclear reactors along the U.S. East Coast are being prepared for potential loss of power and damage from high winds and storm surges as Hurricane Irene bears down on the region.
Nuclear plants in Irene’s path continued to operate as workers secured loose equipment, checked diesel fuel supplies for backup generators and stowed cots and food for workers who may be stranded during the storm.
At Dominion Resources Inc.’s Millstone nuclear station, which sits on a narrow peninsula in the Long Island Sound near Waterford, Connecticut, workers were examining flood barriers and submarine doors designed to keep reactors dry from a hurricane’s storm surge.
“That’s part of our storm preparations: ensuring those flood barriers are in place, ready to do their job,” said Ken Holt, a spokesman for Richmond, Virginia-based Dominion, in an interview yesterday.
Irene, a Category 3 hurricane, is on track to become the first major storm to strike the U.S. since Hurricane Ike in 2008, following a similar path to Gloria in 1985, which swept through New York City into New England.
More than 65 million people from North Carolina to Maine live in the projected path of the storm, according to data compiled by Bloomberg News. National Hurricane Center forecasts show Irene first making landfall along North Carolina’s Outer Banks tomorrow before sweeping north and east through the most populous region of the country.
Entergy Corp.’s Indian Point plant, about 35 miles from midtown Manhattan, is monitoring the storm, which is expected to reach that area as soon as Aug. 28, said Jerry Nappi, a plant spokesman.
The storm’s winds pose a greater threat to the switch yards and power lines that support a nuclear plant than the reactors themselves, which sit beneath containment structures of steel-reinforced concrete, Alex Marion, vice president of nuclear operations for the Nuclear Energy Institute, an industry trade group, said in an interview.
Emergency planning at nuclear plants is in the spotlight following Japan’s Fukushima Dai-Ichi reactor meltdown earlier this year. The disaster occurred after a magnitude-9 earthquake in March triggered a 40-foot tsunami that damaged the station and wiped out unsecured diesel generators.
Power Losses Expected
PJM Interconnection LLC, the grid operator that coordinates electricity transmission across much of the region in Irene’s anticipated path, is preparing for power outages caused by storm winds and falling tree branches, Ray Dotter, PJM’s spokesman.
Federal rules require nuclear plant operators to shut down reactors as hurricane-force winds approach. If lesser winds cut power to a station, nuclear reactors are designed to automatically shut down and switch to backup power to keep fuel cool.
“We have identified by now the plants that could be at risk because of high winds or water surges,” Dotter said in an interview. “We’re looking at what would be necessary to replace them.”
Storm surge is a concern for coastal plants such as Progress Energy Inc.’s Brunswick station in North Carolina, said Jim Riccio, a nuclear-policy analyst in Washington for Greenpeace USA, which is opposed to nuclear power.
Backup Generators Ready
Other plants, including Constellation Energy Group Inc.’s Calvert Cliffs facility in Maryland, and Public Service Enterprise Group Inc.’s Hope Creek and Salem facilities in southern New Jersey are at risk of losing power from the electric grid, depending on the storm’s path, he said.
“They’re all at risk of a loss of off-site power,” Riccio said. If that happens, diesel generators are supposed to automatically kick in.
Federal regulations require nuclear reactors to be in a “safe shutdown condition,” cooled to less than 300 degrees Fahrenheit, two hours before hurricane-force winds strike, the Nuclear Energy Institute’s Marion said.
To comply, plant operators typically begin shutting down reactors 12 hours before winds exceeding 74 miles per hour are predicted to arrive, said Roger Hannah, a spokesman with the U.S. Nuclear Regulatory Commission’s Region II office in Atlanta, in an interview.
“We closely monitor, every hour, the storm track and intensity to determine potential for impact to the site,” said Indian Point’s Nappi in an e-mail.
Backup generators powered Tennessee Valley Authority’s Browns Ferry plant in Tennessee and Dominion’s Surry station in Virginia this spring after tornados damaged power lines leading to the plant, Marion said.
Diesel generators are secured behind flood-proof walls at U.S. nuclear plants, said Hannah, which stock a federally mandated seven-day supply of fuel. All plants in coastal areas of the country are typically built behind berms designed to withstand flooding, Hannah said, and key components and equipment are housed in watertight buildings.
Although Irene’s storm surge is expected to cause widespread flooding in coastal areas, it shouldn’t carry the destructive force of the Fukushima tsunami. “There’s a big difference between a storm surge and a large tsunami,” Hannah said.