The Nuclear Regulatory Commission (NRC) is seeking public comment on whether faster removal of spent reactor fuel from reactor pools to dry cask storage significantly reduces risks to public health and safety.
Based on previous research showing earthquakes present the dominant risk for spent fuel pools, a recent draft study evaluated how pool leakage from a potential earthquake might cause the spent fuel to overheat and release radioactive material to the environment. NRC issued a news release June 24 saying it was seeking public comment.
The draft study concludes there is approximately a one-in-10-million-years chance of a severe earthquake causing a radioactive release from the pool at the site examined.
The NRC began the study following the March 2011 Fukushima nuclear accident in Japan, where the spent fuel pools survived a strong earthquake.
The study considered a spent fuel pool similar to those at Fukushima and 23 other U.S. reactors, and an earthquake several times stronger than what the pool’s design considered. The study examined both a “full” spent fuel pool and one with less fuel and more spacing between individual fuel assemblies, as well as emergency procedures for adding water to the pool in the unlikely event that the earthquake causes the pool to lose water.
“Our detailed analysis showed that even a very strong earthquake has a low probability of damaging the pool studied to the point of losing water,” said Brian Sheron, Director of the NRC’s Office of Nuclear Regulatory Research. “The draft study also shows that even if this particular pool was damaged, the fuel could be kept safely cool in all but a few exceptional circumstances. We’ll use the final study to inform further analysis of U.S. spent fuel pools,” Sheron said.
The NRC will incorporate public comments and use the final study in a broader regulatory analysis of the spent fuel pools at U.S. operating nuclear reactors as part of its lessons learned from Japan.
NRC will be taking public comment for 30 days following publication of a Federal Register notice, which is expected shortly.
NRC also works on waste confidence issue
The NRC also said June 24 that it is making certain documents publicly available in connection with the so-called “waste confidence” rule.
“The waste confidence documents represent a major milestone in the NRC’s effort to address last year’s U.S. Appeals Court decision striking down our waste confidence rule,” NRC said June 24 in its agency blog. “The court directed the agency to analyze the environmental effects of never having a permanent repository for the nation’s commercial spent fuel, as well as the effects of spent fuel pool leaks and fire.”
At issue is continued on-site storage of spent nuclear fuel well beyond the licensed life for operation of a reactor.
The three waste confidence documents being made available include:
• A staff paper to the Commission (SECY-13-0061) recommending publication of a proposed rule and draft generic environmental impact statement, or GEIS, for public comment;
• A draft Federal Register notice containing the proposed rule and a “Statement of Considerations,” or preamble, that explains the rule, the conclusions in the GEIS that support the rule, and the changes in format that the NRC is recommending as part of this rulemaking; and
• The draft generic environmental impact statement on the effects of continued storage of spent fuel; it serves as the regulatory basis for the proposed rule. A list of reference documents used in preparing the GEIS is also being posted on the NRC’s waste confidence webpage.
The NRC staff is proposing a 75-day public comment period on documents issued in connection with the waste confidence ruling.