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series title The NRC and Nuclear Power Plant Safety in 2013 More Jekyll, Less Hyde The NRC and Nuclear Power Plant Safety in 2013 More Jekyll, Less Hyde David Lochbaum March Union of Concerned
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series title The NRC and Nuclear Power Plant Safety in 2013 More Jekyll, Less Hyde The NRC and Nuclear Power Plant Safety in 2013 More Jekyll, Less Hyde David Lochbaum March 2014 2014 Union of Concerned Scientists All rights reserved David Lochbaum is director of the Nuclear Safety Project for the UCS Global Security Program. The Union of Concerned Scientists puts rigorous, independent science to work to solve our planet s most pressing problems. Joining with citizens across the country, we combine technical analysis and effective advocacy to create innovative, practical solutions for a healthy, safe, and sustainable future. More information about UCS and the Nuclear Safety Project is available at the UCS website (www.ucsusa.org). The full text of this report is available on the UCS website (www.ucsusa.org/publications) or may be obtained from: UCS Publications 2 Brattle Square Cambridge, MA Or or call Cover photo: Blue light from the interaction of radiation with cooling water illuminates the core of a nuclear research reactor. ( U.S. Nuclear Regulatory Commission) Printed on recycled paper ii union of concerned scientists [ contents ] v vi Figures and Tables Acknowledgments 1 executive summary chapter 1 3 The Cop on the Nuclear Beat 3 The Reactor Oversight Process and Near-Misses 6 The Scope of This Report chapter 2 7 Near-Misses at Nuclear Power Plants in Arkansas Nuclear One Units 1 and 2, AR 11 Browns Ferry Nuclear Plant Units 1, 2, and 3, AL 12 Columbia Generating Station, WA (First Incident) 12 Columbia Generating Station, WA (Second Incident) 12 Columbia Generating Station, WA (Third Incident) 14 Fort Calhoun Station, NE 15 LaSalle County Station Units 1 and 2, IL 19 Oyster Creek Nuclear Generation Station, NJ 21 Shearon Harris Nuclear Power Plant, NC 23 Susquehanna Steam Electric Station Unit 2, PA 26 Observations on the Near-Misses in 2013 chapter 3 27 Trends from Near-Misses The NRC and Nuclear Power Plant Safety in 2013 iii chapter 4 30 Positive Outcomes from NRC Oversight 30 Connecting the Dots on Component Aging 31 Putting Georgia on Probation 31 Allowing Fort Calhoun to Restart 33 Not Doing What It Said It Would Do 33 Observations on Effective NRC Oversight chapter 5 35 Negative Outcomes from NRC Oversight 35 Mismanaging the Spent Fuel Pool Risk 38 Conspiring to Delay Safety Fixes at Oconee 39 Allowing Diablo Canyon to Operate 41 Improperly Hiding Information 43 Observations on Ineffective NRC Oversight chapter 6 45 Summary and Recommendations 47 References iv union of concerned scientists [ figures and tables ] figures 9 Figure 1. Near-Misses in 2013 by Cornerstones of the Reactor Oversight Process 16 Figure 2. Electrical Distribution System at the LaSalle Nuclear Plant 22 Figure 3. Metal Tubes Penetrating the Reactor Vessel Head 25 Figure 4. The Bathtub Curve 35 Figure 5. Fukushima Public Meetings 37 Figure 6A. Risk from Spent Fuel Pool Storage 37 Figure 6B. Risk from Dry Storage 42 Figure 7. Risk of Core Damage at Oconee from Various Threats tables 5 Table 1. Seven Cornerstones of the Reactor Oversight Process 8 Table 2. Near-Misses at Nuclear Power Plants in Table 3. Near-Misses The NRC and Nuclear Power Plant Safety in 2013 v [ acknowledgments ] This report was made possible through the generous support of the Park Foundation and members of the Union of Concerned Scientists (UCS). The author greatly appreciates the peer reviews of the draft report conducted by Paul Blanch, an electrical engineer who retired from the nuclear industry after a long and distinguished career; Arnie Gundersen, chief engineer for Fairewinds Energy (http://fairewinds.org); and Lucas W. Hixson, the editor-inchief of Enformable Nuclear News (www.enformable.com). The technical editing by Teri Grimwood, program researcher at UCS, was extremely helpful and much appreciated. Trudy E. Bell did a great job with the meticulously helpful final editing as she had done with last year s report in this series. And Bryan Wadsworth, publications director at UCS, deserves much credit for facilitating the editing, layout, and printing of the report on a very tight schedule. The opinions expressed herein do not necessarily reflect those of the organizations that funded the work or the individuals who reviewed it. vi union of concerned scientists viii union of concerned scientists [ executive summary ] Robert Louis Stevenson s classic Strange Case of Dr. Jekyll and Mr. Hyde, first published in 1886, dealt with the split personality experienced by the friendly and mild-mannered Dr. Henry Jekyll and his alter ego, the evil Mr. Edward Hyde. Stevenson s short novel is brought to mind by the apparent dual personality and bizarre behavior traits of the U.S. Nuclear Regulatory Commission (NRC). On one hand, the NRC is a fair and effective regulator, establishing and enforcing safety regulations that subject neither nuclear plant owners to undue burdens nor workers and the public to undue risks. While no one can count the number of accidents that the NRC s efforts have averted, the trend over the past three decades in the declining number of near-misses and safety problems is highly suggestive that much of the time the agency does its job well. On the other hand, the NRC sometimes acts as if it is channeling Mr. Hyde. Inconsistencies in the NRC s actions and inactions last year (2013) invoked both Jekyll and Hyde. As described below in Chapter 2, the NRC s inspectors repeatedly compelled the owner of the Columbia Generating Station to identify and correct the underlying causes of recurring problems with a vital air conditioning unit. But after identifying several examples of inadequate procedures and training at the LaSalle nuclear plant, the NRC s inspectors let the owner off the hook entirely. Yet, when very similar problems surfaced at the H.B. Robinson and Browns Ferry nuclear plants, the NRC compelled the owners to rectify the deficiencies. The strange cases of the Fort Calhoun and Diablo Canyon nuclear plants provide further evidence of the NRC s dichotomy. As described below in Chapter 4, the NRC did not allow the Fort Calhoun reactor in Nebraska to operate until known safety shortcomings were corrected. Yet as described in Chapter 5, the NRC allowed the two reactors at the Diablo Canyon plant in California to continue operating despite its owner failing to resolve known safety shortcomings. The unresolved problems at Diablo Canyon involve inadequate protection against earthquakes. When similar earthquake protection deficiencies were identified at the Beaver Valley, Humboldt Bay, Maine Yankee, San Onofre, Surry, and West Valley nuclear facilities, the NRC s Dr. Jekyll ordered them shut down until their owners had provided adequate protections against the earthquake hazards. Yet today, the NRC s Mr. Hyde allows Diablo Canyon to operate despite the known risks. Giving the NRC the benefit of doubt, one might assume there are nuances explaining why entirely opposite reactions to the same set of facts can somehow both be right. The strange case of Oconee clearly shows this is not the case. As described in Chapter 5, the NRC approved an amendment to the operating licenses for the three reactors at the Oconee Nuclear Station in Seneca, South Carolina, in 2010 contingent on its owner completing safety fixes by December 31, The owner asked the NRC in July 2012 for permission to extend this deadline by two years. In January 2013, the NRC s Dr. Jekyll denied the request on the grounds that the risk was too high to allow the fixes to be delayed that long. But in July 2013, the NRC s Mr. Hyde ordered the company to complete the fixes no later than November 15, 2016 nearly two years after the owner s initial extension request that had been rejected as being too unsafe. A second strange case of Oconee covered in Chapter 5 involved the NRC s Dr. Jekyll formally requiring the plant s owner in June 2010 to take more than a dozen measures to U.S. Nuclear Regulatory Commission The NRC and Nuclear Power Plant Safety in lessen the chances that the upstream Jocassee Dam (owned by the same company) could fail and to better protect the plant against flooding in the event the dam fails anyway. The NRC s justification for this mandate included its determination that if the dam failed, there was a 100 percent chance that flooding would cause the three reactors at Oconee to melt down. The NRC s Mr. Hyde then intervened to improperly withhold all the correspondence about this hazard from the public. Worse still, the NRC conducted its annual public meeting in the community near the Oconee nuclear plant in April 2011, a month after tsunami flooding caused three reactors at Japan s Fukushima Daiichi Nuclear Power Station to melt down. The exact same flooding hazard that exists today at the Oconee nuclear plant was not mentioned by the NRC so the public was actually misled into believing no such problems existed. To be sure, the NRC is far more Jekyll than Hyde, as evidenced by the improving trends over the past three decades. But with so many American lives at stake, even a cameo appearance by the NRC s Mr. Hyde is too much. If an earthquake near Diablo Canyon or a failure of the Jocassee Dam harmed people, the NRC would be unable to look Americans in the eyes and honestly claim it had taken every reasonable measure to prevent the disaster. More Jekyll, less Hyde is this critic s choice for the NRC s future. 2 union of concerned scientists [ chapter 1 ] The Cop on the Nuclear Beat The U.S. Nuclear Regulatory Commission (NRC) is to owners of nuclear reactors what local law enforcement is to a community. Both are tasked with enforcing safety regulations to protect people from harm. A local police force would let a community down if it investigated only murder cases while tolerating burglaries, traffic violations, and vandalism. The NRC must similarly be the cop on the nuclear beat, actively monitoring reactors to ensure they are operating within regulations, and aggressively engaging owners and workers over safety violations whether small, medium, or large. The Union of Concerned Scientists (UCS) has evaluated safety issues at nuclear power plants in the United States for over 40 years. We have repeatedly found that NRC enforcement of safety regulations is not timely, consistent, or effective. Our findings match those of the NRC s own internal assessments, as well as of independent agents such as the NRC s Office of the Inspector General and the federal Government Accountability Office (GAO). Seldom does an internal or external evaluation conclude that a reactor incident or unsafe condition stemmed from a lack of regulations. Like UCS, these evaluators instead consistently find that the NRC s enforcement of existing regulations is inadequate. We have also repeatedly found the NRC to be capable of enforcing its safety regulations. Because we believe the NRC s problem to be consistency rather than capability, we feel the appropriate remedy is to help the agency move toward more consistent and aggressive enforcement. This report like its predecessors chronicles what the agency is doing right as well as what it is doing wrong. Our goal is to help the NRC achieve more of the former and avoid more of the latter. The Reactor Oversight Process and Near-Misses The NRC monitors safety levels at nuclear plants using its Reactor Oversight Process (ROP). In this process, the NRC s full-time inspectors assess operations and procedures, attempting to detect problems before they become more serious. The ROP features seven cornerstones of reactor safety (Table 1, p. 5). Using this process, the NRC issued nearly 200 reports on its findings last year alone. 1 When an event occurs at a reactor or a degraded condition is discovered, the NRC evaluates the chance of damage to the reactor core. A key nuclear safety principle called defense-in-depth means that many protective measures must fail for the reactor core to be damaged. The NRC estimates the degree to which the event or degraded condition has reduced the number of protective measures preventing core damage. Most incidents at nuclear power plants have low risk. If the event or condition did not affect that risk or if the risk was increased only by a very small amount the NRC relies on routine measures in the ROP to respond. When an event or condition increases the chance of reactor core damage by a factor of 10, however, the NRC is likely to send out a special inspection team (SIT). When the risk rises by a factor of 100, the agency dispatches an augmented inspection team (AIT). And when the risk increases 1 See for the NRC s safety inspection reports. The NRC and Nuclear Power Plant Safety in NRC inspection teams are dispatched only when something is believed to have increased the chances of such an accident by at least a factor of 10. by a factor of 1,000 or more, the NRC sends an incident inspection team (IIT). Because they are in response to an event or discovery at a site, the NRC considers its SIT, AIT, and IIT efforts to be reactive inspections (NRC 2011). When an event or discovery at a reactor results in the NRC sending out a team for a reactive inspection, UCS refers to it as a near-miss. Over the years, using this label has proven to be more controversial than expected. UCS continues to use this term because it indicates a clear nexus to accidents involving core damage: the NRC inspection teams are dispatched only when something is believed to have increased the chances of such an accident by at least a factor of 10. In other words, the NRC dispatches inspection teams when it believes safety margins have been significantly reduced, placing the reactor closer to an accident. Near-miss seems a more appropriate and more accurately illustrative label than the NRC s own term, accident sequence precursor. When NRC inspection teams are sent out, they go to a site to investigate what happened, why it happened, and whether the incident poses any safety implications for other nuclear plants. The teams take many weeks to conduct an investigation, evaluate the information they gather, and document their findings in a publicly available report. Both routine ROP inspections and investigations by the special teams may identify violations of NRC regulations. The NRC classifies violations in five categories, with Red The NRC conducts routine inspections of nuclear plants and investigates unusual events at the plants. U.S. Nuclear Regulatory Commission 4 union of concerned scientists table 1. Seven Cornerstones of the Reactor Oversight Process Initiating Events Mitigating Systems Barrier Integrity Emergency Preparedness Public Radiation Safety Occupational Radiation Safety Security Conditions that, if not properly controlled, require the plant s emergency equipment to maintain safety. Problems in this cornerstone include improper control over combustible materials or welding activities, causing an elevated risk of fire; degradation of piping, raising the risk that it will rupture; and improper sizing of fuses, raising the risk that the plant will lose electrical power. Emergency equipment designed to limit the impact of initiating events. Problems in this cornerstone include ineffective maintenance of an emergency diesel generator, degrading the ability to provide emergency power to respond to a loss of offsite power; inadequate repair of a problem with a pump in the emergency reactor-core cooling system, reducing the reliability of cooling during an accident; and non-conservative calibration of an automatic temperature set point for an emergency ventilation system, delaying its startup longer than safety studies assume. Multiple forms of containment preventing the release of radioactive material into the environment. Problems in this cornerstone include foreign material in the reactor vessel, which can damage fuel assemblies; corrosion of the reactor vessel head; and malfunction of valves in piping that passes through containment walls. Measures intended to protect the public if a reactor releases significant amounts of radioactive material. Problems in this cornerstone include emergency sirens within 10 miles of the plant that fail to work, and underestimation of the severity of plant conditions during a simulated or actual accident, delaying protective measures. Design features and administrative controls that limit public exposure to radiation. Problems in this cornerstone include improper calibration of a radiation detector that monitors a pathway for the release of potentially contaminated air or water to the environment. Design features and administrative controls that limit the exposure of plant workers to radiation. Problems in this cornerstone include failure to survey an area properly for sources of radiation, causing workers to receive unplanned exposures; and incomplete accounting of individuals radiation exposure. Protection against sabotage that aims to release radioactive material into the environment; this can include gates, guards, and guns. After 9/11, the NRC removed discussion of this cornerstone from the public arena. SOURCE: SEE denoting the most serious, followed by Yellow, White, Green, and Non-Cited Violations. 2 The color assigned by the NRC for a violation is sometimes related to how much it increased the risk of reactor core damage. But many violations do not lend themselves to such numerical analysis, such as those associated with inadequate radiation protection of plant workers. In general, Red findings from the NRC reflect highest risk and lower performance while Green findings indicate lowest risk and higher performance. The NRC issues non-cited violations not just as oxymorons. Instead, non-cited violations flag situations that do not rise to even the Green threshold, but that reflect unacceptable behavior the NRC wants plant management to correct. For certain violations that do not lend themselves to classification by their risk significance, the NRC uses four severity levels, with level I being the most severe and level IV the least serious. For example, the NRC s regulations prohibit the falsification of maintenance and test documents. The NRC s security regulations require protection against sabotage. It is difficult to assess how violations of either of these regulations might affect core damage risk, and thus how to assign the appropriate color. In such cases, the NRC assigns severity levels instead, considering such factors as whether senior managers 2 For security violations (as opposed to safety violations), the NRC uses a Greater than Green classification instead of White, Yellow, and Red labels to convey to the public some distinction about the seriousness of security problems without also pointing potential saboteurs to plants having especially serious security vulnerabilities. The NRC and Nuclear Power Plant Safety in were aware of or involved in the violations and whether the violations were caused by deliberate acts or sloppy practices. The classifications dictate the thoroughness of the responses the NRC expects from plant owners as well as the extent of the NRC s follow-up to the violations. For example, for a Green finding, a plant owner would be expected to fix the non-conforming condition and NRC inspectors might verify proper resolution during their next planned examination of that area, whether that opportunity was scheduled within a month or a year. For a Yellow or Red finding, however, the plant owner would be expected to also take steps to determine whether the problem was an isolated case or reflective of a broader, programmatic breakdown. Moreover, the NRC s follow-up inspections are typically more timely for Yellow and Red findings than for Green and White findings. This detailed review of all the near-misses reported in 2013 provides important insights into trends in nuclear safety. The Scope of This Report Chapter 2 summarizes the near-misses at nuclear reactors that the NRC re
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