The Tennessee Valley Authority (TVA, NYSE: TVC) is now taking steps to correct concerns over safety at its three-unit, 3,440 MW Browns Ferry nuclear power plant in Alabama. In May of this year, the U.S. Nuclear Regulatory Commission (NRC) said the October 2010 failure of a low pressure coolant injection valve at the plant was of “high safety significance.” This finding resulted in an NRC inspection and increased oversight of the facility.
On Oct. 7, 2011, NRC Chairman Gregory Jaczko and Tennessee Republican Senator Lamar Alexander toured the Browns Ferry plant with TVA employees as part of a three-step inspection program of the plant being led by the NRC. Jaczko said that the plant is in the NRC’s “more intensive inspection programs” due to problems that were noticed in October 2010. The Commissioner said that the staff at TVA is addressing the issues in order to return the plant to the condition that TVA and the NRC wants it to be in.
“Clearly, TVA and the folks at Browns Ferry recognize these challenges and they have accepted our conclusions and are working to get these issues fixed,” he said during a media conference call.
On Oct. 23, 2010, the valve failed to open when operators attempted to use the residual heat removal shutdown cooling loop during Unit 1 refueling, the NRC noted. TVA said that the last time the valve had been definitely worked, as required, was in March 2009 when the loop was placed in service. When discussed in April 2011, TVA said the failed valve was a result of defective manufacturing, but still would have opened and supplied the necessary cooling water, if needed. The system is counted on for core cooling during certain accident scenarios and the valve failure left the system inoperable, which, the NRC said, could have led to core damage, although the public was never in danger. The NRC review in April disagreed with TVA and said the violation was “red” or of “high safety significance.”
During the Oct. 7 tour of the plant, Jaczko said that although the valve was the main issue, he did identify equipment that was in need of improvement and is not as reliable as both the NRC and TVA would like to see it.
“As we do these inspections and we go in and start looking a little more closely, we have indentified other equipment that is in need of better maintenance,” he said.
The valve issue has now been corrected. TVA is aware of the other problems and is replacing motors that power some other pumps and is in the midst of a large program to replace a number of motors for pumps in other systems.
Even though the Unit 1 Browns Ferry reactor containment design is similar to those at the Fukushima Daiichi nuclear power plant (GE Mark 1), Jaczko said there are still significant differences and that there is no determination that Browns Ferry cannot be operated safely. Sen. Alexander, a strong supporter of nuclear energy, reiterated Jaczko. He said the NRC has to continue, and is, making sure that nuclear reactors in the U.S. operate safely. Alexander noted that although the Three Mile Island accident in 1979 is considered the most-recognized disaster in the U.S., no one was hurt.
“No form of energy production in the United States has a better safety system than nuclear power,” said Alexander.
Alexander said that TVA moving towards its goal of leading the nation in new nuclear is good news for the citizens of the Tennessee Valley region. Nuclear power currently provides about one-third of electricity in the region. As coal plants close, he said, nuclear in the future will make up roughly 40 percent of the needed electricity.
“It helps us have cleaner air and it helps us have the kind of low cost electricity that attracts the auto industry to Tennessee and provides better jobs,” he said.
Commissioner Jaczko said there are still challenges ahead for TVA and Browns Ferry, but the NRC has no intent to shut down the plant. If something new arises, he said the NRC will address it as needed. The NRC does evaluate all plants in the U.S. on a continuous basis and will continue to do so. And, “if we ever see something that we believe would prevent the plant from ultimately providing the basic level of safety that is necessary, then we would take an action to shut down a plant,” he said.
Browns Ferry, though, is not in that category.
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