Published: February 02, 2012
A relatively severe accident at a nuclear plant like Dominion Virginia Power's Surry Power Station would be significantly less dangerous than federal regulators previously thought, an NRC study says.
Even if accidents run out of control, the Nuclear Regulatory Commission research study said, they would "take much longer to happen and release much less radioactive material than earlier analyses suggested."
Such accidents "would cause essentially zero immediate deaths and only a very, very small increase in the risk of long-term cancer deaths," the agency said of the study released Wednesday.
The NRC's State-of-the-Art Reactor Consequence Analyses project examined the potential consequences of severe accidents at the Surry plant, about 50 miles southeast of Richmond, and the Peach Bottom Atomic Power Station near Delta, Pa. The plants were selected for study because they are typical of the two main types of U.S. power reactors.
The draft study validates the design and operation of Dominion Virginia Power's four atomic power stations, said David A. Heacock, president and chief nuclear officer of the company's subsidiary Dominion Nuclear: "These plants are inherently safe."
Risk of harm to the public in the types of accidents considered would be low because people would have ample time to evacuate out of harm's way, Brian Sheron, director of the NRC's Office of Nuclear Regulatory Research, said in a teleconference Tuesday.
Nuclear power critics disagreed with that view.
"The study … confirms an obvious fact — that fatalities from acute radiation exposure will be small if effective evacuation of close-in areas occurs before large radiological releases occur," said Edwin Lyman, senior scientist with the Union of Concerned Scientists in Washington. "It says nothing about the potential for acute fatalities should releases occur before effective evacuation."
And, said Paul Gunter with the Maryland-based Beyond Nuclear, "the agency and the industry have collaborated to trivialize the cost and public health consequences of a severe radiological accident at a nuclear power plant.
Assumptions the NRC employed in the study, Gunter said, "are not based in reality and known human behavior that can lead to less rosy outcomes and consequences," for instance traffic jams as people try to flee from radiation exposures.
Past studies of the consequences of a catastrophic accident at Surry estimated that deaths would be in the thousands. The NRC has said earlier research was so conservative as to invalidate those results.
Begun in 2007, the study released Wednesday used updated information about the plants' operations, local populations and emergency preparedness plans, and analyzed the data with state-of-the-art computer modeling incorporating research into actual reactor accidents, the NRC said.
The pilot project focused on the more important severe accident scenarios for Surry and Peach Bottom, the federal agency said. "We picked the most likely of the unlikely" potential accidents, NRC spokesman Scott Burnell said.
The project's preliminary findings said existing resources and procedures can stop an accident, slow it down or reduce its impact before it can affect the public.
However, the study did not look at the most catastrophic of scenarios, Lyman noted.
The study considered plant damage caused by earthquakes and random events, and also considered what would happen if the reactor operators took no action at all to respond to the accidents.
The study's results are specific to the Surry and Peach Bottom plants, but they may be generally applicable to plants with similar designs, like Dominion Virginia Power's North Anna Power Station in Louisa County. "Additional work would be needed to confirm this, however, since differences exist in plant-specific designs, procedures, and emergency response characteristics," the study said.
Dominion Virginia Power volunteered to participate in the research effort, the company said.
"This study comes at a perfect time for Dominion Virginia Power as the industry is in the process of understanding the Fukushima Daiichi nuclear accident in Japan and will incorporate both short- and long-term appropriate actions based on lessons learned from this event," the Richmond-based utility said in a statement. "We will use the NRC (study) data to strengthen our operations and improve the safety of our nuclear units beyond the very safe levels we have already achieved."
Dominion Virginia Power's North Anna and Surry nuclear plants provide about 40 percent of the electricity the company generates in the state.
The company's two 980-megawatt nuclear reactors at North Anna tripped off line Aug. 23, when a magnitude-5.8 earthquake hit central Virginia. The power station shut down automatically without damage to safety systems, unusual release of radioactive material or risk to the public, officials said. Both restarted in November.
Surry was included in the NRC study because it is generally representative of U.S. operating reactors using the Westinghouse pressurized-water reactor design with a large reactor containment building, while Peach Bottom is typical of U.S. reactors using the General Electric boiling-water reactor design with an older type of containment system.
The NRC will meet with the public to discuss the study from 5 to 9 p.m. Feb. 21 at the Surry County Courthouse.
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