Dry cask storage has inherent safety advantages over spent fuel pool storage
Apr 11 2011
Washington, D.C. – U.S. Senator Dianne Feinstein (D-Calif.), chairman of the Senate Appropriations Subcommittee on Energy and Water, today urged Nuclear Regulatory Commission Chairman Gregory Jaczko to consider immediate reforms to the storage of spent nuclear fuel at U.S. commercial reactors.
In a letter to Jaczko, Senator Feinstein asks the NRC to establish regulations that would implement “a more rapid shift of spent fuel to dry casks.”
According to “Safety and Security of Commercial Spent Nuclear Fuel Storage,” a report published in 2006 by the National Research Council at the request of Congress, dry cask storage systems have inherent safety advantages over spent fuel pool storage.
Senator Feinstein in March examined nuclear fuel storage in an Energy and Water Subcommittee hearing on nuclear safety and how natural disasters in Japan affected nuclear facilities there.
Text of Senator Feinstein’s letter follows:
April 8, 2011
The Honorable Gregory Jaczko
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001
Dear Chairman Jaczko:
I am writing to ask that you seriously consider regulatory policies that would encourage the movement of nuclear fuel, once sufficiently cool, out of spent fuel pools and into dry cask storage systems. I am concerned that current Nuclear Regulatory Commission policies allow excessive re-racking and densification of radioactive fuel within spent fuel pools. In fact, there are examples in the U.S. where nuclear fuel rods have been stored in spent fuel pools for decades.
According to “Safety and Security of Commercial Spent Nuclear Fuel Storage,” a report published in 2006 by the National Research Council at the request of Congress, dry cask storage systems have inherent safety advantages over spent fuel pool storage. The report highlighted three main differences between these two storage options:
- Less spent fuel is at risk in an accident or attack on a dry storage cask than on a spent fuel pool. An accident or attack on a dry cask facility would likely affect only a few casks at a time. An accident or attack on a spent fuel pool places the entire fuel inventory at risk.
- The consequences of an accident or terrorist attack on a dry cask storage facility are lower than those for a spent fuel pool. If an accident or attack on a dry cask facility resulted in radioactive material being released, the dispersion could likely be contained easier than if a spent fuel pool were compromised.
- The recovery from an attack on a dry cask would be much easier than the recovery from an attack on a spent fuel pool. Containing radiation that could be released from damage to dry casks can be plugged temporarily with radiation-absorbing materials until permanent fixes are available. Containing radiation from a compromised spent fuel pool is likely to be much more difficult, particularly if the overlying building collapsed preventing workers from reaching the pool.
When taken together, these points assert that the risk of a non-recoverable accident decreases when spent nuclear fuel is kept in smaller, easier to manage, containers that are distributed intelligently on a secure site. The continuous re-racking and addition of fuel rods in spent fuel pools appears to be at odds with these safety recommendations. Based on these findings, I ask the NRC to initiate a rulemaking process to immediately require a more rapid shift of spent fuel to dry casks.
The lesson from Japan’s disaster is that we must be prepared to respond to unanticipated threats. Therefore, any policy changes that further reduce risks of an unsafe situation catching the industry off guard should be implemented. I look forward to working with you further on this issue.
Subcommittee on Energy and Water Development