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Japan

Technological Lessons from the Fukushima Dai-Ichi Accident

by Cynthia Dion-Schwarz, Sarah Evans, Edward Geist, Scott Warren Harold, V. Ray Koym, Scott Savitz, Lloyd Thrall

Following the devastating Tohoku earthquake and tsunami that afflicted Japan in March 2011, some of the reactors of the Fukushima Dai-Ichi nuclear power plant began to release radioactive material into the environment. This study draws lessons from this experience regarding technological countermeasures to radioactive contamination to improve responses to future radiological or nuclear contingencies. Specifically, it focuses on how technologies were used to measure contamination over space and time, to limit the dispersal of radioactive material in the environment, to decontaminate areas or items, and to store radioactive materials for extended periods. The authors gathered data by conducting extensive literature reviews and dozens of interviews with experts in both Japan and the United States. The report analyzes how technologies were used successfully and identifies capability gaps that could be redressed through novel technologies or improved use of existing technologies. Also included is an abbreviated bibliography for further reading.

Key Findings

Characterizing the Extent of Contamination

  • Rapidly deployable sensors capable of surveying large areas quickly are critical for both initial characterization and on-going monitoring of a radioactive dispersal event.
  • In addition, more finely grained local sensors suitable to support the establishment and maintenance of safe corridors and staging areas along with hardened unmanned sensor-carrying systems would be needed.
  • Gaps in knowledge about the extent of contamination early in the Fukushima disaster prevented fully effective responses by officials. Thus, information technologies to quickly and accurately share and display sensors' radiological measurements in real time are needed to support disaster response.

Preventing Radiation Damage and Further Dispersion of Material

  • Better individual monitoring and protection, such as improved hazmat suits, personal dosimetry, and personalized medical approaches to radiation hazards for humans, is needed to ensure worker and resident safety. The lack of such technologies contributed to the negative public perceptions and fear about the event.
  • Where people must venture into contaminated areas, having means of protecting them for long periods without imposing great physical strain would be valuable. One approach might be the use of "exoskeleton" suits that would shield them with an outer layer of lead while also providing them with filtered air and enhanced strength.
  • Approaches to preventing land agricultural uptake of cesium and strontium exist today, facilitating the safety of locally grown food. However, prevention of sea-life contamination remains difficult. Public perceptions about the safety of local food motivate technological development in this discipline.
  • Dust-suppression methods in the local area were effective, but large-scale water management remains challenging.

Decontamination and Collection of Radioactive Material

  • Open-area decontamination methods for structures and land are available but labor-intensive on the large scale found at Fukushima Dai-Ichi.
  • Open-area decontamination of water at large scale remains unsolved, although chemical methods show promise.
  • Biological methods of decontaminating agricultural areas show promise, especially if they can cost-effectively reduce labor requirements for decontaminating large areas.

Disposing of Contaminated Materials

  • The large scale of contaminated material — many thousands of tons of dirt, debris, and water — preclude easy isolation from the general population. Unfortunately, no known method exists to accelerate radioactive decay at this large scale, so the material must be isolated and stored.
  • Nuclear burning to accelerate decay could be investigated as a potential future technology, but particular attention should be given to its scaling potential.
  • In addition, public concern about local storage of nuclear-contaminated material will powerfully shape the choice of technological solutions, so developers should consider the public acceptance of such technologies before embarking on an extensive program of work.

Robotics Issues

  • Unmanned ground vehicles for environmental characterization and response need to be tailored to the needs of austere, contaminated environments. Specifically, they require improved mobility to overcome diverse types of obstacles, high degrees of autonomy due to limited communications bandwidth, the ability to deftly manipulate objects and penetrate small spaces, long dwell times in the environment, and for those systems in the most hazardous areas, radiation hardening through improved circuit design or shielding.

Lessons from the Chernobyl Experience

  • Although astounding societal technological progress has been made in the 25-plus years since the Chernobyl disaster, many of the nuclear mitigation techniques first used by the Soviets in 1986 have changed surprising little.

Table of Contents

  • Chapter One Introduction
  • Chapter Two Characterizing the Extent of Contamination
  • Chapter Three Preventing Radiation Damage and Further Dispersion of Material
  • Chapter Four Decontamination and Collection of Radioactive Material
  • Chapter Five Disposing of Contaminated Materials
  • Chapter Six Robotics Issues
  • Chapter Seven Earlier Lessons from the Chernobyl Experience
  • Chapter Eight Conclusions and Recommendations

Read the report online