Fukushima Event Research Articles

On the value and costs of protective actions in a nuclear emergency

This paper reviews the current orthodoxy for the prompt application of shelter and evacuation advice in the event of a nuclear emergency in the light of the reassessment of the perceived costs and benefits of these protective actions that followed the Fukushima event. In particular, it discusses the mechanisms and criteria for the withdrawal of protective action advice or their continuation for more than a few hours and their impact on public perception. It suggests that lack of thought given to this area may lead to protective actions being kept in place for longer than necessary leading to more harm than good. It also considers the language used to recommend protective actions and to modify them as the event unfolds. Would over strong language used at the start of the event to encourage compliance contribute to public concerns later? Finally, the report poses some discussion points.

Ultra-low-level measurements of airborne fission products from the Fukushima Daiichi reactor accident using high volume collection systems at Savannah River National Laboratory

Ultra-low-level measurements of radionuclides in air have been conducted at the Savannah River National Laboratory (SRNL) to determine the atmospheric concentration of fission products released following the Fukushima Daiichi reactor accident on March 11, 2011. Air filter samples were acquired from two high-volume collection systems (a traditional filter-based system and an electrostatic precipitator-based system) to monitor airborne radionuclide concentrations in the period covering from 2 weeks to 3 years after the disaster. The world-wide spread of low-level concentrations of airborne fission products from the Fukushima event provided a unique opportunity to demonstrate SRNL's electrostatic particle collection technology and other improvements in environmental monitoring developed at the Savannah River Site (SRS). Detecting and analyzing the release allowed a comprehensive test of SRS systems for monitoring environmental radioactivity. Gamma-ray-emitting fission products (131,132I, 134,136,137Cs, and 129,132Te) and cosmogenic isotopes (7Be and 22Na) in air were detected and quantified by high-resolution gamma-ray spectroscopy at concentrations as low as 0.07 μBq per standard cubic meter (SCM) (50 mBq total 137Cs), while plutonium content was quantified by thermal ionization mass spectrometry (TIMS) at concentrations as low as 6.5 × 10−21 g/SCM (3.0 fg 239+240Pu). Isotope concentrations measured at SRNL from gamma-ray spectroscopy were compared to independent measurements from Chapel Hill, NC, located approximately 370 km (230 mi) NE of SRNL. Meteorological modeling was also used to predict radionuclide transport from the location of release to both measurement locations.

Disruption, Disaster and Transition: Analysis of Electricity Usage in Japan from 2005 to 2016

This research analyzes the changes to electricity generation and demand in Japan following both the Global Financial Crisis and Disaster of March 2011. Monthly electricity demand and generation data for all regions of Japan from April 2005 to March 2016 were reviewed to identify differences in disruption-response between different types of electricity users. We apply inferential statistics to identify underlying trends, which we find are dominated by differences in user scale response. Higher capacity users reduced demand in response to the Global Financial Crisis, whereas smaller domestic scale users reduced electricity demand after the Disaster. Analysis reveals that regions within the 50Hz grid that were directly impacted by the Fukushima event and resulting load restrictions showed a statistically significant sustained reduction in monthly electricity demand post-disaster. However, Kansai and Shikoku, regions that are both outside the area directly impacted by the Fukushima event, also showed the same sorts of sustained significant reductions. By considering two disruptions to the same sociotechnical system we can draw conclusions that add to the discourse of electricity use behaviors, which informs both disaster response planning and policy for the broader issues of electricity demand reduction for climate stabilisation. In particular, the results highlight the importance of tailoring engagement and intervention actions to the preferences and needs of different types of electricity users.

Source evaluation of 137Cs in foodstuffs based on trace 134Cs radioactivity measurements following the Fukushima nuclear accident

We performed gamma-ray analysis to determine the amount of radioactive cesium-134 (134Cs) and cesium-137 (137Cs) in 259 foodstuffs five years after the Fukushima nuclear accident of 2011. Using measurements of trace 134Cs radioactivity, we investigated the contribution ratio of 137Cs derived from the Fukushima accident on 2011 and pre-Fukushima. The median detected concentration of radiocesium (134Cs + 137Cs) in foodstuffs was 0.33 Bq/kg-raw, a much lower radioactivity than the Japanese regulatory limit. However, a few samples had particularly high radioactivity, including some dried mushrooms sold in Iwate Prefecture that had a 137Cs radioactivity concentration as high as 441 Bq/kg. Our analysis showed that 75.5% of the 137Cs detected in these mushrooms originated from the Fukushima accident, and 24.5% was originated before the Fukushima event. Our study clarified the 137Cs contamination in 75 of all 259 food samples before and after the Fukushima nuclear accident, showing that not only mushrooms but also fish had been contaminated before the Fukushima accident.

Of Disasters and Dragon Kings: A Statistical Analysis of Nuclear Power Incidents and Accidents.

We perform a statistical study of risk in nuclear energy systems. This study provides and analyzes a data set that is twice the size of the previous best data set on nuclear incidents and accidents, comparing three measures of severity: the industry standard International Nuclear Event Scale, the Nuclear Accident Magnitude Scale of radiation release, and cost in U.S. dollars. The rate of nuclear accidents with cost above 20 MM 2013 USD, per reactor per year, has decreased from the 1970s until the present time. Along the way, the rate dropped significantly after Chernobyl (April 1986) and is expected to be roughly stable around a level of 0.003, suggesting an average of just over one event per year across the current global fleet. The distribution of costs appears to have changed following the Three Mile Island major accident (March 1979). The median cost became approximately 3.5 times smaller, but an extremely heavy tail emerged, being well described by a Pareto distribution with parameter α = 0.5-0.6. For instance, the cost of the two largest events, Chernobyl and Fukushima (March 2011), is equal to nearly five times the sum of the 173 other events. We also document a significant runaway disaster regime in both radiation release and cost data, which we associate with the "dragon-king" phenomenon. Since the major accident at Fukushima (March 2011) occurred recently, we are unable to quantify an impact of the industry response to this disaster. Excluding such improvements, in terms of costs, our range of models suggests that there is presently a 50% chance that (i) a Fukushima event (or larger) occurs every 60-150 years, and (ii) that a Three Mile Island event (or larger) occurs every 10-20 years. Further-even assuming that it is no longer possible to suffer an event more costly than Chernobyl or Fukushima-the expected annual cost and its standard error bracket the cost of a new plant. This highlights the importance of improvements not only immediately following Fukushima, but also deeper improvements to effectively exclude the possibility of "dragon-king" disasters. Finally, we find that the International Nuclear Event Scale (INES) is inconsistent in terms of both cost and radiation released. To be consistent with cost data, the Chernobyl and Fukushima disasters would need to have between an INES level of 10 and 11, rather than the maximum of 7.

Reassessing the safety of nuclear power

We summarize the results of a recent statistical analysis of 216 nuclear energy accidents and incidents (events). The dataset is twice as large as the previous best available. We employ cost in US dollars as a severity measure to facilitate the comparison of different types and sizes of events, a method more complete and consistent that the industry-standard approach. Despite significant reforms following past disasters, we estimate that, with 388 reactors in operation, there is a 50% chance that a Fukushima event (or more costly) occurs every 60–150 years. We also find that the average cost of events per year is around the cost of the construction of a new plant. This dire outlook necessitates post-Fukushima reforms that will truly minimize extreme nuclear power risks. Nuclear power accidents are decreasing in frequency, but increasing in severity.

Workshop 1 – Dosimetry in Research and Test Reactors and in Accelerators

Considerable effort is being expended on the review and documentation of older data. One motivation for this is the need for customers to duplicate the test conditions for work that may have been performed decades ago. Another is the need to properly archive data for the increasing number of facilities that have already been shut down in Europe, the United States and Japan, or are scheduled to be shut down in the near future. Other reasons exist, but the inability of facilities to meet performance requirements imposed after the Fukushima event was identified as a major contributor. Beyond the need to perform extensive review and documentation of experiments already conducted in order to preserve this knowledge for future use, it is important that facilities stopping operation in the near future identify the data that still need to be obtained, and perform the necessary experimental work before the shutdown occurs. Reactors in operation continue to maintain their usual activities with regard to detector calibration and code validation. Although decreasing in number, there still exist reactors with standard fields for calibration and code validation, such as those at SCK-CEN in Belgium and a new critical assembly under construction in Nevada in the United States. The option to seek access to the reactors in China

The PREPARE project − Innovative integrated tools and platforms for radiological emergency preparedness and post-accident response in Europe

The 3-year PREPARE project that started in February 2013 aims to close gaps that have been identified in nuclear and radiological preparedness in Europe following the first evaluation of the Fukushima disaster. Among other issues, the project will address the review of existing emergency preparedness and response procedures for dealing with long-lasting releases, cross-border problems in monitoring and food safety, and further develop missing functionalities in decision support systems ranging from improved source term estimation and dispersion modelling to the inclusion of hydrological pathways for European water bodies. In addition, as the management of the Fukushima event in Europe was far from optimal, a so-called Analytical Platform will be developed exploring the scientific and operational means to improve information collection, information exchange and the evaluation of such types of disasters. This will be achieved through a collaboration of industry, research and governmental organisations in Europe, taking into account the networking activities carried out under the NERIS-TP project. Furthermore, the NERIS Platform member organisations (so far 50 partners) will be actively involved in the development of the new tools.

Investigation of clay bricks for storage facilities of radioactive-wastage

Shielding is an integral part of any radiation facility, it is the method used for radiation protection. Safe storage of nuclear waste materials has become an important issue after Fukushima event. In Japan and France surface facilities are being considered for the storage of low-activity radioactive wastes. At these surface facilities, compacted clay liner obtained from clayey soil has been used as a cap barrier. The purpose of clay liner is to minimize the permeation of moisture, especially due to rainfall, through the barrier up to the radioactive material. Thereby it also reduces the emanation probability of undesirable radon gas and gamma-rays into the atmosphere. The brainchild behind the present investigation is to find the possibility of the burnt clay bricks to be used in these surface storage facilities. The present study aims to evaluate the gamma-ray shielding behaviour of burnt clay bricks in energy range 0.001–15MeV. The samples of bricks were collected from four local brick-factories located near Bathinda-Ferozpur road, Punjab (India). An existing computer programme, Gamma Ray Interaction Coefficients (GRIC)-toolkit was modified for theoretical calculations of some interaction parameters for selected sample. Mineralogical study using X-Ray Diffraction (XRD) followed by Rietveld refinement (XRD-R) has been found in good agreement with Wavelength Dispersive X-Ray Fluorescence (WDXRF) investigation of samples for chemical compositions. XRD-R could be an interesting tool to recognize the radiation attenuation characteristics of materials. It has been concluded that local burnt clay bricks own the moderate gamma-ray shielding abilities while brick of clay (M-0) shows comparatively superior shielding behaviour. Thus brick of clay is the suitable candidate in the construction of environmentally-safe storage facilities for radioactive waste.

U.S. housing prices and the Fukushima nuclear accident

Did the nuclear catastrophe at Fukushima in March 2011 cause individuals to reappraise the risks they attach to nuclear power plants? We investigate the change in home prices in the U.S. after the Fukushima event to test the hypothesis that home prices in the proximity of power plants fell due to an updated nuclear risk perception. Using a difference-in-differences approach, we do not find evidence in support of the hypothesis that individuals reappraised the risks associated with nuclear power plants. According to our results home prices close to nuclear reactor sites did not fall relative to home prices at other locations in the U.S.

Research efforts for the resolution of hydrogen risk

During the past 10 years, the Korea Atomic Energy Research Institute (KAERI) has performed a study to control hydrogen gas in the containment of the nuclear power plants. Before the Fukushima accident, analytical activities for gas distribution analysis in experiments and plants were primarily conducted using a multidimensional code: the GASFLOW. After the Fukushima accident, the COM3D code, which can simulate a multidimensional hydrogen explosion, was introduced in 2013 to complete the multidimensional hydrogen analysis system. The code validation efforts of the multidimensional codes of the GASFLOW and the COM3D have continued to increase confidence in the use of codes using several international experimental data. The OpenFOAM has been preliminarily evaluated for APR1400 containment, based on experience from coded validation and the analysis of hydrogen distribution and explosion using the multidimensional codes, the GASFLOW and the COM3D. Hydrogen safety in nuclear power has become a much more important issue after the Fukushima event in which hydrogen explosions occurred. The KAERI is preparing a large-scale test that can be used to validate the performance of domestic passive autocatalytic recombiners (PARs) and can provide data for the validation of the severe accident code being developed in Korea.

Metabolism: Utopian Urbanism and the Japanese Modern Architecture Movement

The Fukushima catastrophe has led to important practical and conceptual shifts in contemporary Japanese architecture which in turn has led to a re-evaluation of the influential 1960s Japanese modern architecture movement, Metabolism. The Metabolists had the ambition to create a new Japanese society through techno-utopian city planning. The new generation of Japanese architects, after the Fukushima event, no longer seek evolutionally social change; rather, the disaster has made them re-consider what architecture is and what architects can do for people who had everything snatched from them by technology (nuclear power station) and nature (earthquake and tsunami). Drawing on the architectural projects of Tange Kenzo and Metabolists in the 1960s and Ito Toyo’s ‘Home-for-All project’ in 2011, the paper explores this major paradigm shift in Japanese architectural theory and practices.

Climate and Energy Policy in the eu and Germany at a cross roads

For decades the eu claimed for itself political leadership in fighting climate change. Less than two years from now to the global climate conference in Paris (in 2015), however, the eu’s climate policy stands at a cross roads: The eu can leave its impact weak or it decides to strengthen it showing global leadership in international climate policy making again. The situation is similar in Germany. Europe’s self-styled climate policy leader and architect of an economy-wide energy transformation (“Energiewende”) that followed the Fukushima events in 2011, the country now finds itself embattled by industry, political interest groups and consumers, and it risks losing track. If political leaders wish to save the “Energiewende” – certainly one of the boldest political reforms in decades – they need to get serious about putting it into practice.

Strengthening reliability in high hazard industries: reconciling tensions for impact

Purpose– Recent lapses in the management of high hazard organizations, such as the Fukushima event or the Deepwater Horizon blast, add considerable urgency to better understand the complicated and complex phenomena of leading and managing high reliability organizations (HRO). The purpose of this paper is to offer both theoretical and practical insight to further strengthen reliability in high hazard organizations.Design/methodology/approach– Phenomenological study based on over three years of research and thousands of hours of study in HROs conducted through a scholar-practitioner partnership.Findings– The findings indicate that the identification and the management of competing tensions arising from misalignment within and between public policy, organizational strategy, communication, decision-making, organizational learning, and leadership is the critical factor in explaining improved reliability and safety of HROs.Research limitations/implications– Stops short of full-blown grounded theory. Steps were made to ensure validity; however, generalizability may be limited due to sample.Practical implications– Provides insight into reliably operating organizations that are crucial to society where errors would cause significant damage or loss.Originality/value– Extends high reliability research by investigating more fully the competing tensions present in these complex, societally crucial organizations.

Monte Carlo simulation analysis of integral data measured in the SCK-CEN/ENEA experimental campaign on the TAPIRO fast reactor. Experimental and calculated data comparison

After Fukushima events, the Italian nuclear program has been redefined leaving space only to activities related to Generation IV nuclear systems. Accordingly with this renewed national scenario, TAPIRO fast reactor facility is gaining a relatively major strategic role. A program is in fact being proposed to host in TAPIRO benchmark experimental activities related to the development of Lead fast reactor and Accelerator Driven Systems. A first step of this program would consist on the validation of neutronic codes, cross section data and reactor models to be adopted for its analysis. Along this line in this work the results of a simulation study has been made relevant to the measurements performed in the SCK-CEN/ENEA experimental campaign carried out in the 1980–1986 period. The calculations have been made using the Monte Carlo MCNPX 2.7.0 Code. In this article the main results are presented and discussed, with particular emphasis on the uncertainties, relevant both to nuclear data and the model layout. The results of this simulation study indicate in particular that TAPIRO's MCNPX model is adequate for the optimization of set-ups of perspective neutron irradiation experiments, this allowing cuts in costs and development time.

Feed-in tariff for solar photovoltaic: The rise of Japan

Japan started implementing a national Feed-In Tariff (FiT) mechanism on the 1st July 2012, which included specific payment tariffs for solar photovoltaic (PV) installations. This marks a new era in the renewable energy landscape in Japan. This paper aims at analysing the solar PV prospect in Japan, particularly in both residential and non-residential sectors. The paper presents, first, an overview of energy trends in Japan prior to the Fukushima event. This is followed by a short review of solar PV progress in the country, highlighting the major policies and programmes that have been implemented as well as the installations that have been carried out over the past two decades. Next, the financial impact of the new FiT scheme on consumers is evaluated. The financial analysis investigates the total profit, the average annual return on investment and the payback period. For a comparison purposes, a similar financial analysis is also conducted with selected countries around the world – namely Germany, Italy and the United Kingdom. The results from this analysis indicate that the new Japanese FiT rate generates a good profit, a moderate annual return on investment and an acceptable payback period, suggesting an increasing trend of solar PV uptake over the next years.

Insights on Accident Information and System Operations during Fukushima Events

As part of the development of an integrated perspective on lessons learned from the Fukushima Daiichi nuclear accident, this paper highlights lessons learned and implications relating to the accident information and system operational aspects during the events. Our analysis clearly indicates that the plant was neither designed nor prepared to withstand such an unexpected event, which included a complete loss of electrical power sources for a long period. The author focused on the accident information and system operational aspects of the Fukushima event, including lack of information, provision of wrong information, operator performance in life-threatening environments, and improvisation given lack of procedures and training. Suggestions for further improvement of the nuclear plant safety are then made with respect to preparation for beyond design basis events, provision of reliable essential information to operators, development of guidelines/procedures, training of operators, and development of operator support systems with consideration of severe accidents caused by unexpected events. It is hoped that the lessons learned from the accident will significantly contribute to the enhancement of nuclear plant safety.

The impact on the competence on severe accidents following the Fukushima event

Abstract Fukushima related questions are currently being addressed at Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) mbH within several research projects funded by the Federal Ministry for Environment, Nature Conservation and Nuclear Safety (BMU) and Federal Ministry of Economics (BMWi). In the following section first results of selected issues are presented.

U.S. Housing Prices and the Fukushima Nuclear Accident: To Update, or Not to Update, that is the Question

Did the nuclear catastrophe at Fukushima in March 2011 cause individuals to reappraise the risks they attach to nuclear power plants? We investigate the change in housing prices in the U.S. after the Fukushima event to test the hypothesis that house prices in the proximity of power plants fell due to an updated nuclear risk perception. Using a difference-in-differences approach we do not find evidence in support of the hypothesis that individuals reappraise the risks associated with nuclear power plants. House prices close to nuclear reactor sites did not fall relative to house prices at other locations in the U.S.

OS1417 原子炉格納容器試験体の弾塑性FEMを用いた解析評価

As one of responses to Fukushima event, structural integrity evaluation of Containment Vessel (CY) at severe accident has been promoted. This paper is intended to perform the elastic-plastic analysis of the pressure confirmatory testing of the Steel CV made in the past, to establish a method for analysis and evaluation at severe accident. Differences between test and analysis should be corrected using techniques ASME Sec. VIII which considers the effects of multiaxiality. Moreover, it is confirmed that the difference of equivalent plastic strain about 2.1 times between the test and analysis, caused by material discontinuities in the weld, for example. In ductile fracture assessment, it should be properly corrected this correction factor.