By Tom Kauffman
How safe is nuclear energy? It’s a question many Americans are asking a year after the accident in Japan. Pennsylvanians should know that all U.S. nuclear energy plants have been thoroughly evaluated by the U.S. Nuclear Regulatory Commission and deemed safe. Equally important is the fact that the nuclear industry and the NRC are applying the lessons learned from the accident in Japan to make a safe source of electricity even safer.
To further bolster plants’ ability to withstand extreme events, the NRC has ordered improvements that include reanalyzing risks posed by floods and earthquakes, equipping multiunit facilities to simultaneously protect all their reactors, installing additional instruments to monitor used fuel storage pools, augmenting safety equipment added after the 9/11 attacks, assessing emergency communications if electrical power were lost and, for some reactors, installing hardened vent systems.
Within days of the Fukushima accident, the U.S. nuclear industry launched intensive inspections to evaluate the readiness of the operators and equipment to respond to events similar to what happened in Japan, including managing an extended loss of power for vital safety systems and seismic and flooding challenges. The inspections identified key areas for near-term safety enhancements. The industry forged ahead to make those enhancements.
In February, the nuclear officers of all the companies that own and operate nuclear energy facilities in the U.S. unanimously agreed to actions that will strengthen key safety systems against severe natural or manmade events.
The plants already have multiple emergency generators, battery banks, backup off-site power supplies, extra pumps and compressors, some of which were added after the attacks of 9/11. Now the companies have acquired or ordered additional backup safety equipment — more than 400 large generators, pumps, etc. — to ensure power can be delivered to critical safety systems under any conditions. The existing and new equipment, along with regional emergency supply centers that are being planned, will greatly expand the resources that plant operators can draw on to ensure plant safety during severe conditions.
Through the decades, U.S. nuclear power plants have been struck by hurricanes, tornadoes, earthquakes and floods. Without exception, all have performed as designed to protect the health and safety of the public and the environment.
Last August, for example, Hurricane Irene caused flooding and damage along the East Coast. Of the 24 nuclear facilities in Irene’s path, 18 remained at full power, four temporarily reduced output, one temporarily shut down as a precaution, and one in Maryland automatically shut down when storm debris struck an external electrical transformer. After the storm, the plants provided electricity for the recovery.
Pennsylvania’s nine nuclear power plants, which generate 95 percent of the commonwealth’s low-carbon electricity, withstood Hurricane Irene and have a strong record of reliability. The plants’ combined reliability rating of 95 percent is above the nuclear industry’s national average.
The U.S. nuclear industry’s high level of safety and reliability is driven by the lessons learned from the accident at Three Mile Island in 1979. TMI was a game-changer for the industry.
Following the accident investigation, many actions were taken to permanently improve and strengthen industry safety measures, including codifying its “defense-in-depth” strategy, forming a tough watchdog organization called the Institute of Nuclear Power Operations, strengthening the NRC’s powers and using full-scale control room simulators for operator and emergency training at every plant.
The plants have emergency preparedness programs that are second to none, and an industrywide safety culture program encourages workers at all levels to take an active role in plant safety and freely report safety concerns.
The U.S. industry responded similarly after the terror attacks of Sept. 11, 2001, improving security at U.S. reactor sites while confirming our reactors can sustain the impact of a deliberate airline crash without releasing radiation that would harm the public.
Looking forward, we will continue to expect the unexpected, imagine the worst case scenarios, and plan for them. Although none of the nuclear facilities in America faces earthquakes or tsunamis the magnitude of those that occurred in Japan, and the likelihood of a Fukushima-type accident occurring here is extremely small, it would be foolish to miss the larger lesson: The U.S. nuclear industry must never take safety for granted and will continuously evaluate all 104 reactors to make sure they can withstand severe challenges regardless of the cause.
Tom Kauffman, a lifelong resident of Pennsylvania, worked at Three Mile Island at the time of the accident. He is now with the Nuclear Energy Institute.