A two-page Policy Forum opinion piece titled Nuclear safety regulation in the post-Fukushima era: Flawed analyses underlie lax U.S. regulation of spent fuel by Edwin Lyman, Michael Schoeppner and Frank von Hippel appeared in the May 26, 2017 issue of Science Magazine, an outlet that has a public reputation as a reliable source of technical information.
Aside: The UCS has made an arrangement with Science to provide access to a full version of the May 26 opinion piece. The arranged link can be found embedded in the lede of Dr. Lyman’s May 25 All Things Nuclear blog post titled UCS in Science: The NRC Must Act to Reduce the Dangers of Spent Fuel Pool Fires at Nuclear Plants End Aside.
The authors admit in their final paragraph that their goal is instilling concern and distrust. They are seeking to create sufficient public support for their minority viewpoint that the Nuclear Regulatory Commission (NRC) is so closely aligned with the nuclear industry that it protects the industry from spending money on what the authors assert is a grave risk.
“The larger problem of NRC regulatory capture will be dealt with, however, only when pressure from the concerned public outweighs that from the nuclear industry.”
Spent Fuel Pool Fires
The issue that the three authors claim demonstrated the NRC’s condition as a captured regulatory agency is often referred to as a spent fuel pool fire. Specifically, they are worried about the fact that U.S. spent fuel pools are loaded with a large quantity of fuel assemblies that have been used to generate power and thus contain radioactive isotopes, including cesium-137, a gamma emitting isotope with a 30-year half life. They assert that the potential radioactive contamination problem associated with the material in the spent fuel pools could be reduced by moving assemblies that have been out of reactors for more than five years into licensed dry storage containers.
Their premise is that the public will be better protected if the NRC requires nuclear plant operators to reduce the density of their spent fuel pools and limit the amount of material that could potentially be released.
The NRC has invested many thousands of professional staff hours and and uncounted number of millions of dollars addressing the concerns raised by Lyman, von Hippel, Schoeppner and other critics in an effort that has lasted at least 30 years. Via SECY-16-0100, dated August 24, 2016, Victor McCree, the current Executive Director for Operations at the NRC, reaffirmed the staff’s position on spent fuel pools to the Commission and the public.
That short Policy Issue Information paper has a 22-page enclosure that addresses each of the findings of the National Academy of Sciences work mentioned in the Lyman, von Hippel, and Schoeppner Science Policy Forum opinion piece in excruciating detail.
The following conclusion statement from SECY-16-0100 should set most minds at ease, even if it does not satisfy or quiet the stubborn critics.
The staff concludes that spent fuel continues to be stored safely and securely at nuclear power plants in both spent fuel pools and dry casks. The security of U.S. nuclear power plants remains extremely robust.
The enclosed NRC assessment of the current NAS study reflects an extensive history of how spent fuel safety and security have been assessed and improved in the United States. Significant enhancements to the safety and security of nuclear power plants, including spent fuel pools, were made following the terrorist events of September 11, 2001, and the Fukushima accident in 2011.
Spent fuel pool safety was enhanced at U.S. reactors when licensees implemented new NRC requirements to develop strategies for spent fuel pool cooling following losses of large areas of the plant due to fires, explosions, or extreme natural events. The NRC will continue to cooperate with other federal agencies and international organizations to assess possible threats to nuclear power plants and to improve risk assessment techniques. The staff will continue to bring policy matters to the Commission for consideration and action as appropriate.
(Reference: SECY-16-0100 p. 4. Emphasis and paragraph breaks added.)
Why Does This Issue Periodically Capture Public Attention?
Worries about the radiological consequences of a fire in a spent fuel pool might seem otherworldly to those of us who have seen spent fuel pools and understand that they are 40 feet deep pools of water with very thick concrete walls lined with a thick, penetration-free steel liner. Fires and pools are not two words that go together very well. Until 2001, one could confidently assert that the vast majority of the general public would yawn if told they should worry about a fire in a pool, no matter what kind of pool it was.
In the aftermath of 9-11, Americans were open to hearing about new reasons to be concerned, so people opposed to nuclear energy seized the opportunity provided by the crisis to raise the issue of spent fuel pool fires postulated to be the result of a hypothetical terrorist attack that caused widespread damage at a nuclear plant.
Once again, a crisis presented an opportunity to nuclear opponents. During the Fukushima Frenzy, Dr. Greg Jaczko, then serving as Chairman of the NRC, raised the issue of spent fuel pool fires to a whole new level of public awareness. It is a topic that had been simmering inside the nuclear enterprise for several decades. Most of the people who were aware of the issue had determined that it was highly unlikely and carried relatively low probability of harm even if the rare conditions required somehow were assumed to occur in the proper sequence.
On March 17, 2011, Dr. Jaczko told Congress in a public hearing that the March 11 earthquake and tsunami had successfully created the necessary conditions in the spent fuel pool at Fukushima Unit 4. According to his testimony, the unit 4 spent fuel pool was dry and burning, releasing enough material to support his recommendation to evacuate all U.S. personnel within 50 miles of the Fukushima Dai-ichi nuclear power station.
The Internet is full of articles and commentary that stimulate discussion about spent fuel pool fires; many of them point to Fukushima Unit 4 as either a catastrophe that happened [accuracy is not necessarily the strong suite of historical internet documents or news reports] or a near miss that could have happened.
As a result of the concerns stoked by Jaczko’s testimony, the NRC received strong encouragement from several NGOs and from congressional oversight committees to address the issue. That pressure continued even after the Frenzy had calmed down enough for more sober investigators to determine (p.2) that the spent fuel pool for unit 4 had never come close to being emptied and that the fuel temperature had most likely not exceeded 100 ℃.
“On March 11, 2011, a 9.0-magnitude earthquake struck Japan and was followed by a 45-foot tsunami, which resulted in extensive damage to the nuclear power reactors at the Fukushima Dai-ichi facility. After the onset of core damage in some units, there were significant concerns about the integrity of SFPs and the possible release of radioactive materials from the spent fuel assemblies. However, subsequent inspections determined that pool integrity had been maintained, the integrity of the spent fuel cladding had not been challenged, and equipment to restore coolant inventory had been successfully deployed, despite radiological hazards and extensive damage to the surrounding structures from the tsunami and hydrogen explosions. While the SFPs and the spent fuel assemblies at the site remained intact, the event led to questions about the safe storage of spent fuel and whether the NRC should require expedited transfer of spent fuel to dry cask storage at nuclear power plants.”
The Science Policy Forum piece is part of a sustained effort by the team of Lyman, von Hippel and Schoeppner to create public fear and distrust strong enough to stimulate political action. In the May 24, 2016 issue of Science, Richard Stone published a brief report in Science titled Spent fuel fire on U.S. soil could dwarf impact of Fukushima. That report quoted Lyman and von Hippel and described the dispersal simulation created by Schoeppner in support of a paper that the three were planning to submit to the journal Science & Global Security.
That proposed paper was submitted and accepted. It appeared online on May 8, 2017, less than three weeks before the opinion piece in Science was published.
The three assumed that the NRC had correctly computed the maximum amount of cesium-137 that could be released if there was some kind of initiating event that partially drained a spent fuel pool and prevented any successful efforts by plant operators or first responders. In this “nightmare scenario,” the resulting lack of cooling, combined with the continuing addition of decay heat from fuel assemblies force material temperatures high enough to cause protective cladding to fully react with either air, steam or a combination of the two.
The scenario assumes that the reaction is rapid enough to cause an explosive accumulation of hydrogen gas that ignites and eliminates the retention effect of the building that houses the fuel pool. The reaction is also rapid enough to generate the kind of updraft that will loft material from the pool to a sufficient height that it can be dispersed by winds over distances in excess of 50 miles – 80 km.
Using a source term of 1600 petabecquerels of Cs-137 – 100 times as much as was released by melting three reactor cores at Fukushima – the trio ran simulations in which the release was from the Peach Bottom nuclear station. They computed the contamination levels resulting if the release happened on the first day of each month using weather information from 2015 and created maps of average land concentration. They assumed that all areas in which the land contamination value exceeded 1.5 MBq/m2 would be evacuated.
Based on the government actions following Chernobyl and Fukushima, they expect that the evacuations would turn into long-term relocations with devastating political, economic and mental health consequences.
Their simulations, using the same maximum release value as used by the NRC in its evaluation of the situation, produced an evacuation land area that was three times larger and included five times as many people as the NRC’s worst described case. Based on their consequence results, they believe that the NRC wrongfully chose not to force nuclear plant operators to perform a more rapid transfer of spent fuel out of pools and into dry storage containers. They assert that the NRC’s decision was that of a captured agency responding to industry pressure at the expense of public safety.
Their thesis is that the Commission chose inaction in order to protect the industry from the $5 billion cost of the expedited transfer program and not because the agency determined that the public is more than adequately protected under current conditions.
Regulators Agree There’s No Reason To Worry
The NRC staff’s recommendation to the Commission following its study of the risk and potential consequences of a spent fuel pool fire and the potential benefit of requiring an expedited program of moving fuel from spent fuel pools into dry storage containers is documented in COMSECY-13-0030 dated as follows:
The staff’s assessment concludes that the expedited transfer of spent fuel to dry cask storage would provide only a minor or limited safety benefit, and that its expected implementation costs would not be warranted. Therefore, the staff recommends that no further generic assessments3 be pursued related to possible regulatory actions to require the expedited transfer of spent fuel to dry cask storage and that this Tier 3 Japan lessons-learned activity be closed.
The staff did not reach that recommendation quickly or cheaply. The conclusion is provided as part of a ten page memorandum that enclosed a 159 page supporting document titled Regulatory Analysis for Japan Lessons-Learned Tier 3 Issue on Expedited Transfer of Spent Fuel
That regulatory analysis was based on previously completed work, including a congressionally mandated post-Fukushima effort that was documented in a 416 page study titled Consequence Study of a Beyond-Design-Basis Earthquake Affecting the Spent Fuel Pool for a U.S. Mark I Boiling Water Reactor dated October 2013. I haven’t asked what the entire effort cost, but the Consequences study itself was the result of more than $3 million and 11,000 professional staff hours spent during FY11-FY13.
When asked for a comment in response to the publication of the Science opinion piece questioning the NRC’s competence and integrity as an effective safety regulator, Scott Burnell of the NRC’s public affairs office provided the following statement.
“The staff’s analysis followed well-established, Commission-approved directives for identifying all attributes affected by the proposed alternative and analyzing them either quantitatively or qualitatively (https://www.nrc.gov/reading-rm/doc-collections/commission/secys/2013/2013-0112scy.pdf). The staff’s technical conclusions regarding potential safety benefits were reached before considering potential costs.
The NRC’s current conclusions regarding spent fuel pool safety and security are best summarized by the staff’s response last summer to the National Academies Phase 2 report on lessons learned from Fukushima:
The NRC welcomes well-supported analysis on issues relating to the agency’s mission. The staff will review the Science policy paper and determine whether any additional action is required. Absent such a review, the NRC stands by the conclusions from the staff’s work to date.”
Skeptics Stubbornly Assert They’re Correct
When contacted via email, von Hippel and Lyman stood by their assertions that the NRC had not properly considered the societal cost of a wide-spread relocation effort and the loss of effective economic use of large swaths of heavily populated areas. They asserted that the NRC chose to ignore the possibility of terrorist action while they asserted that terrorists were fully capable of causing the required damage to spent fuel pools while also maintaining enough control of the area to prevent operators from taking any planned or improvised mitigating actions.
“Adams: Can you explain why you and your coauthors think that the public should be so concerned about such improbable event with such a tiny health risk that they should be willing to spend $5 billion to modestly reduce the potential?
von Hippel: I can only speak for myself. I think that the risk that the NRC estimated of 0.14 to 6 percent during the next 20 years of an event that would on average require the long-term relocation of 8 million (our estimate; the NRC estimated 1.3-8.7 million) is significant. On top of that, I would add the terrorist risk. On top of that, I would add that, when we correct the NRC’s cost-benefit analysis, the average probability-weighted benefits would exceed the costs even before taking into account the risk of terrorism.”
When I pressed harder regarding the inability of terrorists to impose the kind of widespread infrastructure obstacles that can be imposed by earthquakes, tsunami or major storms and suggested that the U.S. might be able to avoid the kind of relocations imposed in Ukraine or Japan, Dr. Lyman weighed in with the following additional comments.
“We aren’t alleging that terrorism would necessarily result in worse consequences than accidents. But a deliberate attack can be engineered to induce consequences similar to the most severe, low-probability accidents, yet the NRC’s quantitative risk methodology does not take that into account. What we are proposing is a defense-in-depth measure to reduce the consequences should such an attack occur. And I disagree with you that a terrorist attack would necessarily be of more limited scope than a natural disaster. Terrorists can both interfere with on-site emergency response and deny site access to external responders — tactics that are seen routinely around the world.
And on your last point, our article should make clear that we agree that the societal disruption due to long-term relocation is a significant consequence that is not accounted for in the NRC’s methodology. But it is unrealistic to expect that spontaneous relocation would not take place from contaminated areas even if the government tried to assure people that it was safe to stay. The best way to avoid such impacts is to reduce the risk of such an event in the first place.”
In a second installment, I will address additional considerations and correspondence. But the bottom line here is that the responsible professionals at the Nuclear Regulatory Commission have determined that the public has nothing to worry about regarding the current conditions of spent fuel pools. In contrast, a small group of physicists disagree and want the public to support their quest for expensive political action.
Both before and after writing the above, I engaged in a spirited email exchange with Drs. Frank von Hippel (Princeton University) and Edwin Lyman (Union of Concerned Scientists). Their point of view is fundamentally different from mine and is based on the vast differences in our educational and professional backgrounds. In my view, it is worthwhile to engage in a discussion in public to allow observers a better opportunity to make informed choices on important issues.
Dr. von Hippel provided the following rebuttal to the above post. I will address this response along with additional thoughts about the vast differences in perception between us regarding hazards related to the radioactive material stored in spent fuel pools under current regulations.
On how close the spent fuel in Fukushima pool #4 came to be uncovered, I would reference the discussion in chapter 2 of the National Academy of Sciences report. See especially the discussion associated with Figure 2.15.
With regard to the representation of our work, Rod links only to the article summary because the article itself is behind a paywall. UCS has, however, provided a link to the full article. Ed Lyman can provide that link.
Rod demeans our analysis as only two pages while ignoring the two backup articles in Science & Global Security referenced there, of which he is aware, and for which I have provided links.
Reducing the Danger from Fires in Spent Fuel Pools, Science & Global Security Vol. 24, No. 3, 141–173
Economic Losses From a Fire in a Dense-Packed U.S. Spent Fuel Pool Science & Global Security Volume 25, 2017 – Issue 2 May 2017.
Rod demeans us three as fringe characters while representing the NRC as a font of unbiased wisdom. Although it doesn’t seem to bother Rod, most people find it pretty devastating to the NRC’s credibility when they learn of the omissions and mistakes that we have pointed in the staff’s analysis: ignoring the possibility of terrorism, leaving out consequences beyond 50 miles, and in its computer program secretly increasing the contamination threshold for relocation three-fold and assuming that decontamination by up to a factor of 15 of an area the size of New Jersey can be accomplished within a year.
I would also note that, in his effort to represent us as fringe characters, Rod has ignored that our work builds on the four-year-long National Academy of Sciences study referenced above which includes many of the criticisms that he attributes to us, including the NRC’s refusal to consider the possibility of terrorism and or take into account consequences beyond 50 miles. Indeed, the NRC, in a “sensitivity study” quoted in the NAS report, concluded that including the consequences beyond 50 miles and updating its value for a human life lost to cancer would have increased fivefold the consequences it used in its cost-benefit analysis. That would have brought its cost-benefit analysis to the break-even point without including the possibility of terrorism. The additional errors that we pointed out with respect to relocation threshold and decontamination timescale increased the accident consequences by another factor of three.
Rod’s piece does not even hint at the above. Based on my exchanges with him, his answer that we are wrong and the NRC is right is unchangeable but the arguments on which he bases that conclusion changed completely with each cycle of our exchange. That is why I decided to give up trying to educate him.
You can use the above as a rebuttal. I would request also that you flag our backup articles and add the above links.
Frank N. von Hippel, Senior Research Physicist and
Professor of Public and International Affairs emeritus
Program on Science and Global Security and
International Panel on Fissile Materials
Note: A version of the above was first published on Forbes.com. It has been modified with additional information about the current position of the NRC staff as documented in SECY-16-0100. It is republished here with permission.