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| Fig. 1: Area of impact of the Fukushima Daiichi Disaster. (Courtesy of the National Diet of Japan. [8]) |
The last major nuclear power plant accident occurred in March 2011, at the Fukushima Daiichi nuclear power plant. This incident, impacting over 337 square kilometers, was caused by a magnitude 9.0 earthquake and led many officials to reevaluate their current natural disaster safety standards. In this case study, we will examine how exactly the Fukushima Daiichi disaster occurred and what policy and safety assessment changes were made.
On March 11, 2011, the Great East Japan earthquake (GEJE) with a magnitude of 9.0 occurred just off the NorthEast coast of Japan, setting off a tsunami that would sweep inland to impact the Fukushima Daiichi nuclear power plant. This more than 14-meter tall wave damaged both the main and backup power supply of the power plant, and although all reactors were shut down prior to the tsunami's impact, the sudden loss of power still led to a buildup of heat and pressure in the reactors eventually leading to hydrogen explosions in all reactors.
The main impact of the Fukushima Daiichi accident was on the citizens in the surrounding area. As of 2019, the number of disaster-related deaths was 3701 and 460,000 citizens in the area were displaced from their homes for their safety. As a secondary impact, the loss of the power plant resulted in a 10% reduction in Japan's total power output, which rose to 30% as other nuclear plants were shut down to investigate security concerns and ensure another accident didn't occur. Additionally, the disaster caused $129 billion in direct property damage, $43.5 billion in accumulated damage to critical infrastructure and supply chain, and a $29 billion dollar reduction in agriculture-related activities. [1] In the areas closest to the plant, the gamma counts were above 3 million Bq per square meter. (See Fig. 1.)
As a result of the Fukushima Daiichi incident, several plants around the world were reevaluated for their ability to withstand natural disasters. 132 plants were retested with more rigorous conditions in regard to their safety. After many studies examining this accident, the general consensus was that there needed to first be a clear and more flexible approach to emergency response. [2] There needs to be an uninterruptable line of power to critical infrastructure such as hospitals and first response centers. Also, the response center for a disaster should not be located in an area likely to be impacted by said disaster (as was the case for the Fukushima Daiichi response center). [3]
Several safety standard changes and suggestions resulted from the many studies launched investigating this disaster. Chief among them Japan made reevaluated the safety of their existing, remaining plants through use of computer simulation and reexamine the safety regulations of the NISA which allowed for the falsification of safety reports. [4]
In the US, the current status of safety regulations in the NPP was reexamined in a study, providing recommendations for improvements on plant management and emergency response. [3] The NRC issued a series of orders and requests for information, to 105 US power plants. Chief among these were EA-12-049, EA-12-051, and EA-13-109 which all of which aimed to improve and verify standards and instrumentation in the case of beyond events outside the scope of the original design of the plant. [5]
In Europe, new tools to improve plant safety were developed. [6] The HERCA-WENRA made the first steps at international communication to combat the lack of information that plagued the Fukushima Daiichi disaster response. [7]
However, while there were many studies conducted into the Fukushima Daiichi accident and several plants were reevaluated for their safety during extraneous events, the recommendations made by these studies never translated directly into policy and no plants were found to be unsafe under the new evaluation standards. Essentially, no serious policy changes were implemented other than a soft reevaluation of existing power plants, and one of the primary issues in the Fukushima Daiichi event, the response center being too close to the plant, did not see any significant policy change, enforcing a minimum distance. It is likely that this small policy change was due to the belief that the tsunami causing the disaster was atypical and did not reflect a weakness in the current safety standards. Therefore to restore public confidence in nuclear power plants, some small policy and safety changes were enacted.
The Fukushima Daiichi accident was certainly a tragic accident resulting in many dead and displaced as well as creating resounding consequences for the economy and industry of Japan. In order to prevent such an incident from happening again, many countries and organizations have made efforts to reexamine the safety standards used when developing nuclear power plants. However, despite the many studies and safety recommendations, few actual policy changes have been implemented and what few reevaluations are implemented are cursory at best. While the Fukushima Daiichi accident occurred because of an atypical natural disaster, such atypical events can occur in the future. To prevent future disasters, stronger policy changes should be enacted than those meant simply to restore public faith in nuclear plants.
© Michael Chang. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
[1] Y. Obayashi and K. Hamada, "Japan Nearly Doubles Fukushima Disaster-Related Cost to $188 Billion," Reuters, 8 Dec 16.
[2] "Impacts of the Fukushima Daiichi Accident on Nuclear Development Policies," Nuclear Energy Agency, NEA No. 7212, 2017.
[3] Lessons Learned From the Fukushima Daiichi Nuclear Accident For Improving Safety and Security of U.S. Nuclear Plants: Phase 2 (National Academies Press, 2016).
[4] A. Rinschied, "Crisis, Policy Discourse, and Major Policy Change: Exploring the Role of Subsystem Polarization in Nuclear Energy Policymaking," Eur. Policy Anal. 1, 34 (Fall 2015).
[5] Nuclear Regulatory Commission, "Mitigation of Beyond-Design-Basis Events," 84 Fed. Reg. 39684 (August 9, 2019).
[6] "HERCA-WENRA, Approach For a Better Cross-Border Coordination of Protective Actions During the Early Phase of a Nuclear Accident," Heads of the European Radiological Protection Competent Authorities, October 2014.
[7] W. Raskob et al., "CONFIDENCE: Project Description and Main Results," Radioprotection 55, S7 (2020).
[8] K. Kurokawa et al., "The Official Report of the Fukushima Nuclear Accident Independent Investigation Commission: Executive Summary, The National Diet of Japan, 2012.