The nation's nuclear safety chief said Tuesday he is worried that U.S. nuclear plant operators have become complacent, just nine months after the nuclear disaster in Japan.
Gregory Jaczko, chairman of the Nuclear Regulatory Commission, said recent instances of human error and other problems have endangered workers and threatened safety at a handful of the 65 nuclear power plants in the United States.
Workers at nuclear plants in Ohio and Nebraska were exposed to higher than expected radiation levels, Jaczko said, while three other plants were shut down for months because of safety concerns _ the first time in more than decade that several plants have been shut down at the same time.
The Crystal River nuclear plant in Florida and Fort Calhoun in Nebraska remain shut down, while the earthquake-damaged North Anna plant in Virginia reopened last month after being shut down for three months.
Jaczko said he was not ready to declare a decline in safety performance at U.S. plants, but said problems were serious enough to indicate a "precursor" to a performance decline.
"We need to make sure that (nuclear) licensees continue to do the right thing for safety. That's the number one thing going forward," Jaczko said at a meeting with reporters at NRC headquarters. "There are some things we want to keep an eye on to make sure we are not seeing really true declines in performance."
Jaczko said incidents at Cooper Nuclear Station in Nebraska and Perry Nuclear Power Plant in Ohio "almost led to workers getting very, very significant doses" of radiation. Jaczko blamed the incidents on human error and improper work plans. The incidents show the need to focus on more than plant construction and technical solutions that provide increased protection against earthquakes, floods and fires, Jaczko said.
"The softer side of the safety business can have a real impact," he said, referring to plant operations and worker performance.
In response to the disaster at Japan's Fukushima Dai-ichi plant, the NRC approved a number of steps to improve safety at the nation's nuclear power plants, which have a total of 104 nuclear reactors. The changes are intended to make the plants better prepared for incidents they were not initially designed to handle, such as prolonged power blackouts or damage to multiple reactors at the same time.
"This has been a year driven by events in Japan," Jaczko said.
Even so, the year was remarkable for natural disasters at home.
The North Anna plant in Virginia shut down when an Aug. 23 earthquake caused peak ground movement about twice the level for which the plant was designed.
Other U.S. reactors were threatened by severe flooding in the Midwest and tornado damage in the Southeast.
The NRC has conducted a greater number of special inspections this year _ 20 so far _ than at any point in recent memory, Jaczko said. The inspections were all prompted by site-specific concerns, but could indicate broader problems, Jaczko said.
Tony Pietrangelo, senior vice president of the Nuclear Energy Institute, an industry group, called the past year "challenging," but said the industry is in broad agreement with the NRC's response to the Japan crisis. Specifically, he said the industry is ready to adopt most of the commission's short-term reforms, including one to improve response to prolonged power outages, most likely through additional equipment such as portable pumps, battery chargers, hoses and even bulldozers.
"We are committed to addressing lessons learned from Fukushima through expeditious actions in concert with our regulator, but not at the expense of our focus on day-to-day safe and reliable plant operations," Pietrangelo said.
Two plants, Fort Calhoun and the Browns Ferry nuclear plant in Alabama, have been placed at the NRC's highest level of concern and are subject to additional inspections and public meetings, Jaczko said. Both have had repeated safety problems.
Two other plants, the Perry plant in Ohio and Susquehanna in Pennsylvania, are at the next-highest level of scrutiny. Ninety-one of the nation's 104 nuclear reactors were performing at the highest level and operating with the normal level of inspections.
On other issues, Jaczko said staffing limitations caused by a flat budget could delay license renewals for existing nuclear plants.
"There are resource limitations," he said. It "may take us a little bit longer to get through the reviews" for license renewals.
Jaczko also said he is "very comfortable" with the steps the agency took to close out its review of the Yucca Mountain nuclear waste dump in Nevada.
An inspector general's report released last June said Jaczko intimidated staff members who disagreed with him and withheld information from members of the commission to gain their support. Several high-ranking employees at the independent agency complained that Jaczko delayed and hindered their work on the Yucca project.
Jaczko said the actions he took were consistent with the law.
"Sometimes when you have difficult decisions, you have challenging conversations. I think in the end the agency did its job," he said.
Republicans have accused Jaczko, a Democrat and former aide to Senate Majority Leader Harry Reid of Nevada, of political bias in directing the NRC to stop work on its review of Yucca Mountain. Jaczko denies any wrongdoing.
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