Dominion Resources Inc.’s reactors at its North Anna plant, rattled by an August earthquake, may resume full operation within 10 days after the U.S. Nuclear Regulatory Commission deemed the units safe, the company said.
North Anna’s two reactors were shut on Aug. 23 by the Virginia temblor that exceeded the plant’s design limits. The company plans for both reactors to return to 100 percent operation, Dominion said today in a statement.
The plant is “safe and ready to be restarted,” David A. Heacock, president and chief nuclear officer for Dominion Nuclear, said in the statement. The nuclear plant “suffered no functional damage from the quake,” he said.
Regulators are using the 33-year-old Dominion plant as a model to evaluate earthquake risks because seismic hazards for some nuclear plants in the eastern and central U.S. may be greater than anticipated. Of the 104 commercial U.S. reactors, only eight are west of the Rocky Mountains, where quake hazards are better known, and 52 are at least 30 years old.
North Anna’s reactors, about 11 miles (18 kilometers) from the earthquake’s epicenter near Mineral, Virginia, automatically halted operation during the 5.8-magnitude temblor. NRC and company officials conducted “thousands” of inspections at the plant, which can produce enough electricity to power about 450,000 homes, Dominion said in its statement. The Richmond, Virginia-based company spent $21 million on inspections, testing and analysis at the plant, it said.
Safe To Resume
The NRC earlier today said in a statement that North Anna was safe to resume operations.
“We’re satisfied the plant meets our requirements to restart safely, and we’ll monitor Dominion’s ongoing tests and inspections during startup of both reactors,” Eric Leeds, director of the NRC’s Office of Nuclear Reactor Regulation, said in a statement today.
Dominion has told the NRC it plans to permanently upgrade the plant’s seismic monitoring equipment and steel containers, each weighing about 115 tons, that store nuclear waste, the agency said. North Anna’s storage containers shifted as much as 4.5 inches, Dominion informed the NRC on Aug. 31. The company has also agreed to conduct any needed inspections for the plant’s reactor vessels, the NRC said.
Returning a reactor to normal operations after being shut takes about four days because components including pumps and valves must be put into use in sequence, according to Dominion. North Anna’s Unit 1 reactor has been started and is in its heat-up phase, spokesman Jim Norvelle said.
“We anticipate rejoining the grid and providing electricity to our customers on Monday morning,” he said in an e-mail.
Dominion plans for Unit 2 to resume operations after the first reactor is producing electricity safely, according to the company’s statement. Delays “could occur and are not atypical” in returning nuclear reactors to use, it said.
“Nuclear power is an important component of energy production in the commonwealth, and it is good news that the North Anna Power Station will soon be back online and running,” Virginia Governor Bob McDonnell said in a statement.
The North Anna shutdown has highlighted a separate NRC review of earthquake risks for U.S. commercial power plants.
“North Anna is the test case” for the agency’s broader seismic review, Larry Lane, Dominion’s site vice president for the Virginia plant, told reporters on a Sept. 2 tour.