The Fukushima nuclear disaster was caused by an earthquake and tsunami in March 2011 that knocked out power to the plant. Three reactors suffered core damage and released radiation. Over 18,000 people died from the natural disasters. The accident exposed over 170 emergency workers and 6 workers to radiation above limits. Decommissioning of the damaged reactors is expected to take 30-40 years. Key lessons included the need for stronger safety measures and emergency response plans for earthquakes and tsunamis.

1. Fukushima Nuclear Disaster
in Japan
Prepared By:
Bharat Wagle Gopal Acharya
Roll No. 02 Roll No. 03
Msc. In Public Health and Disaster Engineering
Faculty of Science and Technology
School of Engineering
Pokhara University

2. Introduction
• The accident at the Fukushima Daiichi Nuclear Power Plant that
resulted from the Great East Japan Earthquake of March 11, 2011,
involved the dispersion and spread of radioactive materials.
• The disaster caused the most extensive release of radioactivity since
the Chernobyl accident in 1986 and was far worse than the 1979
Three Mile Island accident in the United States. Unlike at Chernobyl
and Three Mile Island, the destruction at Fukushima was initiated by
natural disasters—a huge earthquake and tsunami—rather than
equipment failure and human error. The tsunami knocked out backup
power systems that were needed to cool the reactors at the plant,
causing several of them to undergo fuel melting, hydrogen explosions,
and radioactive releases.

3. Fukushima Daiichi Nuclear Powerplant
• Fukushima Daiichi is among the world’s largest power plants in
northeastern Japan.
• The Fukushima Dai-Ichi Nuclear Power Station is located in the towns
of Futaba and Ohkuma, 250km north of Tokyo city in Japan.

4. The Great East Japan Earthquake Disaster
• The disaster in northeastern Japan and initiated a severe nuclear
accident at the Fukushima Daiichi nuclear plant.
• Three of the six reactors at the plant sustained severe core damage and
released hydrogen and radioactive materials.
• Explosion of the released hydrogen damaged three reactor buildings
and impeded onsite emergency response efforts March 11, 2011, Great
East Japan Earthquake and tsunami sparked a humanitarian.

5. The Great East Japan Earthquake Disaster
Earthquake
• Magnitude 9.0
• Duration >200sec
Tsunamis
• 6 -7 Tsunamis
• Height >15m
• Rose up to 41m
• Drown 561km2 within 40min- 4h.
Nuclear accident

6. Fukushima Daiichi Nuclear Powerplant

7. CAUSES OF ACCIDENT
• The 2011 Tōhoku earthquake and tsunami was an 9.0 magnitude
earthquake followed by tsunami waves.

8. Accident of Nuclear Power Plant
• The tsunami has led to shut down three active reactors on 11.03.2011
• On 12.03.2011, Hydrogen explosion was happened in Unit 1.

9. Accident of Nuclear Power Plant
• On 13.11.2011, Dropping of the internal pressure has led to explosion in Unit 3.
• On 14-15.11.2011, There was an explosion in Unit 4 fuel storage, after that the fire
has started.
• On 16.03.2011, In Unit 1-3, a %50 portion of the core was under threated from
melting
• 17.03.2011, Helicopters transported water for cooling Unit
• 18-19.03.2011, Cooling unit 3 with water canons provided by police and fire
department units, Unit 3 is considered cooling enough.
• 20-21.03.2011, At around 15:55 light gray smoke is observed from the south part
of the 5th floor of Unit 3.
• 22.03.2011, White smoke seen in Unit 2, until the morning of 22.03 it disappears.
• 23.03.2011, End of water feed of the spent fuel storage pool of Unit 4.

10. Nuclear Power Plant accident: the situation

11. the situation

12. Consequences of the Accident
Damage as a natural disaster
• Death toll: >18,000
• Houses:
>200,000 washed out
>120,000 demolished
Infrastructure
8.9mil. houses blacked out
2.2 mil. houses cut water
1.4 mil. fixed phone disconnected
29,000 cellular phone base were out
Massive damage BEFORE the accident

13. Consequences of the Accident
Effects on alive
Because of released substances, many health problems have occurred.
• For the members of the public at large, the estimates used indicate that the effective
doses incurred were low, and no early radiation induced health effects were observed.
• For children, the reported thyroid equivalent doses were low because their intake
of iodine-131 was limited, partly due to the restrictions placed on drinking water and
food. So far, prenatal radiation effects have not been observed, and unwanted terminations
of pregnancy attributable to the radiological situation have not been reported.
• For the around 23 000 emergency workers involved in the emergency operations, the
effective doses incurred by most were below the occupational dose limits in Japan. Of this
number, 174 exceeded the original criterion for emergency workers, and 6 emergency
workers exceeded the temporarily revised effective dose criterion in an emergency
situation.

14. Consequences of the Accident
Effects on Social Life
The initial decisions on protective actions towards the public included:
evacuation, sheltering, restrictions on the consumption of food and
drinking water, relocation, and the provision of information.
Administration of stable iodine for iodine thyroid blocking was not
implemented uniformly, primarily due to the lack of detailed
arrangements.
The evacuation of people from the vicinity of the Fukushima Daiichi
nuclear power plant gradually extended from a radius of 2 km of the
plant to 3 km, and by the evening of 12 March, it had been extended to
20 km.

15. Consequences of the Accident
Loss of electrical power
The earthquake led to the loss of off-site and on-site electrical power which caused the loss
of the cooling function at the three operating reactor units as well as at the spent fuel pools.
All operating reactor units at these plants were safely shut down but despite the efforts, the
reactor cores in two Units overheated, the nuclear fuel melted, and the three containment
vessels were breached. Explosions inside the reactor buildings damaged structures and
equipment, and injured personnel. The four other nuclear power plants along the coast were
also affected to different degrees by the earthquake and tsunami.
Effects on Economy
At the end of the accident, financial losses reached approximately 150 billion Euro.
Effects on Environment
After the disaster, released substance damaged the environment.

16. Challenges
The challenges in risk communication
1. Type of crisis
• Factors that make the crisis hard to be accepted are:*
• NOT voluntary
• NOT under individuals’ control
• NO benefit
• NOT distributed fairly
• Manmade
• Catastrophe generated by an untrusted source
• Affect children
• All applied to the accident

17. Challenges
2. Combined with huge natural disaster
• Infrastructural damage: Limited information
• Mass casualties by the tsunami
• Communication tools were disrupted
• Perception gap between residents and the company Government &
TEPCO: ‘Risk reduction was not enough, but it was a natural disaster’
Residents: ‘All was human-made disaster’

18. Challenges
3. Historical background ‘ Radiation’ is associated with
• Hiroshima & Nagasaki (Atomic bombs)
• Daigo Fukuryu-maru (A tuna fishing boat exposed to nuclear fallout from the
United States' thermonuclear device test in 1954)
Radiation = Immediate death
4. Cultural background
• Confucian influence: loyalty to one's lord
• Fatalistic: low self-defense
• Spirit of mutual aid: weak leadership*
• Poor media literacy: the effect of the news on the general public is hardly taken
into account; only a few people doubt the validity of the news
Weak culture of risk ‘communication’

19. Cause–effect analysis

20. Remedial measures: post disaster
What is the remediation strategy adopted for the post accident recovery?
• There were no policies and strategies for post-accident remediation in
place in Japan at the time of the accident. A comprehensive high level
strategic plan for stabilization and decommissioning of the damaged
nuclear power plant was developed jointly by TEPCO and the relevant
Japanese Government agencies. At the time of writing, safety
functions had been re-established and structures, systems and
components were in place to reliably maintain stable conditions.
• Japanese authorities have estimated that the timescale for completing
decommissioning activities is likely to be in the range of 30–40 years

21. Lesson learnedWhat main lessons are learned from the Fukushima-Daiichi accident?
• Because of the basic assumption that nuclear power plants in Japan were safe, there was a tendency for
organizations and their staff not to challenge the level of safety and this resulted in a situation where safety
improvements were not introduced promptly.
• Based on the lessons of the accident, the Contracting Parties to the Convention on Nuclear Safety, adopted the
Vienna Declaration on Nuclear Safety. This declaration includes principles to prevent accidents with
radiological consequences and to mitigate such consequences, should they occur after having reported on the
implementation of safety upgrades, including 6 main axes:
• improvement of severe accident management provisions and guidelines ;
• re-evaluation of site specific external natural hazards and multi-unit events ;
• enhancement of power systems ;
• additional means to withstand prolonged loss of power and cooling for the removal of residual heat;
• strengthening of measures to preserve containment integrity
• improvements of on-site and off-site emergency control centres.
• In particular, the assessment of natural hazards needs to consider the potential for their occurrence in
combination, either simultaneously or sequentially, and their combined effects on multiple units of a nuclear
power plant.

22. References
• https://www.psr.org/blog/resource/costs-and-consequences-of-the-
fukushima-daiichi-disaster/
• https://doi.org/10.1080/00223131.2015.1071290
• Hiroko Tabuchi, Keith Bradsher, and Andrew Pollack “Japanese Officials on
Defensive as Nuclear Alert Level Rises,” The New York Times (2011, April
13): http://www.nytimes.com/2011/04/13/world/asia/13japan.html.
• Tabuchi, Bradsher, and Pollack “Japanese Officials on Defensive,”
http://www.nytimes.com/2011/04/13/world/asia/13japan.html
• “Nuclear Accident Disclosure,” Japan Times (2011, July 8):
http://search.japantimes.co.jp/cgi-bin/ed20110708a1.html.
• http://enenews.com/busby-going-fission-occurring-fukushima-either-
recent-enriched-uranium-fission-explosive-criticality