Posted on 30 Oct 2012 by Neilson
Hurricane Sandy forced three nuclear power plants to shut and put another on alert as federal regulators dispatched inspectors to monitor 11 facilities in the path of the storm, the biggest test for the U.S. industry since a crisis in Japan more than 18 months ago.
Public Service Enterprise Group Inc. manually closed its 1,174-megawatt Salem Unit 1, about 18 miles south of Wilmington, Delaware, when four of six circulating pumps were no longer available because of weather, according to Joe Delmar, a company spokesman. The unit operated at full power yesterday, while unit 2 was shut for refueling.
“The biggest challenge for us overnight was waves hitting the circulating water systems at both stations,” Delmar said in an e-mail response to questions. There was also “lots of river grass and debris,” he said.
Sandy, the biggest Atlantic Ocean tropical storm on record, moved along the East Coast for five days before slamming into the mid-Atlantic coast yesterday, unlike the earthquake and tsunami in March 2011 that crippled Japan’s Fukushima Dai-Ichi plant. Still, Sandy may disturb intake of water for cooling or sever plants’ links to external power.
Nine Mile Point in Scriba, New York, was automatically shut down after a power disruption to a switchyard, the U.S. Nuclear Regulatory Commission said. Entergy Corp.’s Indian Point 3 nuclear plant in New York also automatically closed at 10:41 p.m. yesterday because of power-grid issues from the storm, Neil Sheehan, an NRC spokesman based in King of Prussian, Pennsylvania, said today in an e-mail.
The nation’s oldest nuclear plant, Exelon Corp. (EXC)’s Oyster Creek facility in New Jersey, declared an alert last night due to elevated levels of water in its water-intake structure, according to a statement from the NRC. The plant, about 33 miles (53 kilometers) north of Atlantic City and near the center of the storm’s landfall, was already offline for a refueling outage.
“Nuclear plant operators throughout the region had their hands full dealing with this historic storm. While three reactors experienced shutdowns, all are in a safe condition,” Sheehan said in the e-mail. “Inspectors were on duty throughout the storm to keep a close watch on plant conditions and will continue to do so as work on restoring the units to service” begins.
Exelon said last night there was “no challenge to plant safety equipment and no threat to the public health or safety,” according to an e-mailed statement. “Exelon has staffed on-site and off-site emergency operations centers to monitor weather and plant conditions and to provide updated information to local, state and federal officials.”
Exelon said the alert was declared when water rose above 6 feet (1.8 meters) above sea level, the threshold for an alert -- the second-lowest of four levels of emergency declaration. A disruption was also reported at the plant’s switchyard, which delivers power to the plant, though diesel generators kicked in automatically.
Oyster Creek began operating in December 1969 as the nation’s first large-scale commercial nuclear power plant. The company announced in 2010 plans to close it by the end of 2019, when it will have been in operation 50 years. Its single boiling-water reactor produces 645 net megawatts, enough electricity to power 600,000 homes.
On its website, the Chicago-based company called Oyster Creek “a robust and fortified facility, capable of withstanding the most severe weather.” Earlier yesterday, Exelon said it repositioned emergency gear, activated back-up communications and boosted staffing at its three Pennsylvania plants in the path of the storm: Limerick, Peach Bottom and Three Mile Island.
Entergy Corp. (ETR)’s Indian Point 3 nuclear plant in New York automatically shut down at 10:41 p.m. yesterday because of power grid issues from the storm, Sheehan said today in an e-mail.
Constellation Energy Group Inc.’s Nine Mile Point 1 reactor in the state was also shut because of a problem putting power onto the grid, Reuters reported, citing an unidentified NRC spokesman. It wasn’t clear if the outage was related to Sandy, Reuters said, citing the NRC. Nobody answered calls to the press offices of Constellation or the NRC.
The Washington-based NRC sent inspectors armed with satellite phones to facilities from Maryland to Connecticut and said all plants remain in a safe condition. Procedures require plants to shut before winds are forecast to exceed hurricane force, the commission said in a statement yesterday.
“Given the breadth and intensity of this historic storm, the NRC is keeping a close watch on all of the nuclear power plants that could be impacted,” NRC Chairman Allison Macfarlane said in an e-mailed statement. “Our extra inspectors sent to the potentially affected sites will continue, on an around-the- clock basis, to independently verify that the safety of these plants is maintained until the storm has passed and afterwards.”
Analysts said loss of outside power, which is necessary to keep nuclear cores and spent fuel cool, would test adjustments being made at the plants after an earthquake-triggered tsunami led to radiation releases at the Fukushima Dai-Ichi plant in 2011. The Tokyo Electric Power Co. (9501) plant lost off-site power and backup generators failed after the earthquake.
Just as with Fukushima, plant owners “look back to see what flooding heights, wind speeds, etc. have occurred at the site and design their plants to survive repeats,” Dave Lochbaum, director of the Nuclear Safety Project at the Union of Concerned Scientists, said in an e-mail. “But when nature reaches new levels, as at Fukushima, past protections may be insufficient.”
“Designing by rear-view mirror works when nature cooperates and stays consistent with the past,” he said.
U.S. nuclear plants are well-equipped to handle the threats from Sandy, said Arthur Motta, chairman of the Nuclear Engineering Program at Pennsylvania State University. “In terms of comparative risks, a nuclear power plant is safer than most of the other things nearby,” he said in an interview.
Plants in the path of the storm included Indian Point and Calvert Cliffs in Maryland, owned by Constellation Energy Nuclear Group LLC, a joint venture of Exelon and Electricite de France SA in Paris.
“All plants have flood protection above the predicted storm surge, and key components and systems are housed in watertight buildings capable of withstanding hurricane-force winds and flooding,” the NRC said.
At Indian Point, debris in the Hudson River, which could disturb water-intake, poses a greater risk than flooding, Sheehan said in an interview. All the plants in the storm’s path were told to examine their vicinity for large objects that could become “airborne missiles” in high winds, he said.
Given the threat of loss of power, “it would be more responsible if NRC and plant operators would shut the plants down in advance,” Kevin Kamps, a radioactive waste specialist at Beyond Nuclear, a Takoma Park, Maryland, group that seeks to end nuclear power and nuclear weapons, said in an interview.
It takes longer to cool down the radioactive core at a plant operating at full power, he said.
“In terms of reactors, you had better hope those diesel generators work adequately,” Kamps said.
Backup diesel generators and cooling systems at Fukushima failed after a 15-meter surge of water tied to a 9-magnitude undersea earthquake on March 11, 2011, led to the worst nuclear disaster since Chernobyl in 1986. Hydrogen explosions occurred as water in the reactors and spent-fuel ponds boiled away and radiation leaked.
Motta, a member of a National Academy of Sciences panel on U.S. nuclear safety, disagreed and said shutting the plants now wouldn’t make much of a difference.
Hurricane Sandy crossed the New Jersey coast south of Atlantic City. With winds extending 1,100 miles, the storm shut the federal government in Washington and state offices from Virginia to Massachusetts. It halted travel, prevented U.S. stock markets from opening and upended the presidential campaign.