The U.S. Nuclear Regulatory Commission and nuclear utilities said they took steps this week to ensure that power plants in the Carolinas and Virginia were ready for possible impact by Hurricane Florence, which made landfall Friday morning on the Atlantic Coast.
Duke Energy by Thursday afternoon had already begun shutting down its Brunswick nuclear power plant, which is 4 miles inland near the city of Southport, N.C. The two-reactor facility is in the path of the storm and could be hit with hurricane-level winds, surges of water from the nearby Cape Fear River, and large amounts of rain, the NRC said Wednesday.
Rita Sipe, a spokeswoman for the utility, told the Washington Post that the reactor units stand 20 feet higher then sea level and are built to manage a 22-foot storm surge. However, nuclear power plants are required to shut down at least two hours prior to the arrival of hurricane-force winds greater than 73 mph.
“Well-trained, experienced operators and other station employees will remain on-site throughout the storm, continuously monitoring both wind and rainfall, as well as plant equipment,” Duke said in its announcement. “Our operators are skilled at managing events, such as extreme weather, safely shutting down the generating units, and maintaining the units in a safe state until conditions allow for their return to service.”
The Global Nuclear Fuel facility near Wilmington, N.C., where winds Friday afternoon were reported at 105 mph, has also suspended operations and secured gear, the NRC said.
No other nuclear facilities were expected to be required to suspend power production, NRC spokesman Roger Hannah said Thursday. However, the agency said safety steps are being taken at Dominion Energy’s Surry nuclear power plant in southeastern Virginia and Duke’s Harris facility in North Carolina and Robinson site in South Carolina, among others.
In total, the three states host 16 nuclear power reactors, Reuters reported.
Preparations include inspections of cooling pools and dry storage casks for spent reactor fuel, to identify any potential dangers if the storm hits – particularly flying debris that could damage the installations if not secured or removed, according to Hannah.
“Nuclear power plants are probably the most robust structures in the United States. They’re well prepared to withstand natural events, including hurricanes,” Duke Energy spokeswoman Karen Williams told RadWaste Monitor.
Along with the hardened facilities themselves, Duke nuclear personnel are trained to deal with hurricanes or other extreme weather events, Williams said. That includes training simulations every five weeks. Each plant also has a designated emergency team prepared to respond to any emergency.
The nongovernmental Union of Concerned Scientists on Wednesday expressed concerns about potential vulnerabilities at the Brunswick and Surry plants. It noted that Duke in late 2012 informed the NRC that hundreds of flood barriers at Brunswick were missing or deteriorated, and that a 2015 follow-up report was not made public. There is also reason for concern about the capacity of the James River-adjacent Surry facility to deal with flooding produced by large amounts of rain, UCS said.
“Nuclear plants are safe from flooding if plant operators properly install protective measures and designers accurately forecast flooding hazards,” Edwin Lyman, UCS senior scientists and nuclear plant design specialist, said in a press release. “Falling short on either requirement would make a nuclear plant more vulnerable to floods, which could lead to a meltdown.”
Williams said she had not reviewed the UCS concerns in depth, but said Brunswick is both 4 miles inland and more than 2 miles from the Cape Fear River.
“Based on information provided to us related to flood barriers and other protections, and our inspector verifications of storm preparations, the NRC is confident that the Brunswick plant is prepared for the effects of Hurricane Florence,” Hannah stated by email Thursday.
Duke’s nuclear plants in the region have completed their pre-storm readiness work, Williams said, including deploying emergency equipment and ensuring diesel generators have sufficient fuel to sustain operations during any loss of off-site power.
While Williams said she could not discuss specifics of weather emergency planning for spent fuel, she said Duke’s dry casks are made of steel-reinforced concrete designed to withstand hurricanes. Spent fuel pools at nuclear facilities are often elevated, reducing the threat from flooding, Hannah noted.
Dominion Energy, which also operates the North Anna power plant in Virginia, said its dry-storage casks each weigh 115 tons. “Highly unlikely that they will tip over,” spokesman Richard Zuercher said.
The NRC is posting additional inspectors at certain power plants to verify that all necessary emergency measures have been taken. No fewer than two inspectors will be posted at most impacted facilities, and additional officials could be deployed “depending on the damage and any required follow-up inspections or coordination,” according to Hannah. The agency’s Region 2 incident response center in Atlanta will also be online continually during the storm.
