Japan’s Nuclear Accident
- Update -
May 12, 2011
Ministry of Economy, Trade and Industry
Government of Japan
Table of Contents
A. Japan Faces an Unprecedented Challenge (Enormous Earthquake, Tsunamis and Nuclear Accident)
1. Damage
2. Nuclear Power Stations
B. Key Challenges
1. Cool Down the Reactors
2. Contain the Spread of Radioactive Substances (sea, soil and atmosphere)
3. Rigorous and Intensive Monitoring
C. Impact on Energy Supply/Demand
1. Impact on Energy Supply/Demand in Japan
D. Responsiveness to the World
1. Cooperation with International Organizations
2. Speedy Dissemination of Accurate Information
1
Great Support of the International Community
Japan deeply appreciates the assistance
offered from
142 countries and regions and
39 international organizations
Rescue teams from 24 countries
regions and international
organizations
US Navy/US Pacific Command
(Operation Tomodachi)
2
A. Japan Faces an Unprecedented Challenge
(Enormous Earthquake, Tsunamis and Nuclear Accident)
Tsunamis
14 meters or higher
Earthquakes:
M - 9.0 quake (March 11)
M - 7 class 5 times
M - 6 class 63 times
M - 5 class 335 times
TOKYO■
Fukushima Dai-ichi
3
1. Damage
Casualties : over 26,000
・Dead ： over 14,000
・Missing ： over 11,000
Evacuees : over 130,000
(As of April 25th)
KYODO NEWS
KYODO NEWS
NOAA/US Dept of Commerce, http://wcatwc.arh.noaa.gov/
4
2. Nuclear Power Stations
Nuclear Reactors near Epicenter of the Earthquake
4 Nuclear Power Stations with 14 Units
automatic
shut down
Onagawa
Unit 1 524 MW, 1984Unit 2 825 MW, 1995Unit 3 825 MW, 2002Fukushima Dai-ichi
Unit 1 460 MW, 1971Unit 2 784 MW, 1974Unit 3 784 MW, 1976Unit 4 784 MW, 1978Unit 5 784 MW, 1978Unit 6 1,100 MW, 1979Fukushima Dai-ni
Unit 1 1,100 MW, 1982Unit 2 1,100 MW, 1984Unit 3 1,100 MW, 1985Unit 4 1,100 MW, 1987Tokai Dai-ni
Unit 1 1,100 MW, 1978-
cold
shut down
Periodical
inspection
5
2. Nuclear Power Stations
Fukushima Dai-ichi Nuclear Power Station
Before the Earthquake and Tsunamis
After the Earthquake and Tsunamis
TEPCO
Air Photo Service Inc (Myoko, Niigata Japan)
6
2. Nuclear Power Stations
Fukushima Dai-ichi Nuclear Power Station
Cause of the Damage
Huge Tsunami
46 Meter
Grid Line
46 Meter
① Loss of off-site power
due to the earthquake
Reactor
Building
About
40M
About
20M
Turbine
Building
Diesel Generator
② Diesel generator inoperable
due to the tsunami
Elevation:
about 10m
GE Hitachi Nuclear Energy
Tsunami (estimated 14m)
Breakwater
5.4 ~5.7m
Seawater level
All motion operated pumps including
ECCS became inoperable
Seawater Pump
7
B. Key Challenges
1. Cool Down the Reactors
2. Contain the Spread of Radioactive Substances
(sea, soil and atmosphere)
3. Rigorous and Intensive Monitoring
8
1. Cool Down the Reactors
(As of April 25th)
9
1. Cool Down the Reactors
(Unit 1)
（As of Apr 25th, 2011）
Spray
Damaged
Spent Fuel Pool Cooling System
Injecting fresh water
or seawater
The fuel
pellets are
presumed
to be
melting
Major Events
TEPCO
Damaged
Recovered
Emergency Diesel Generator
Residual Heat Removal System
Fuel Bundle
・400
Spent Fuel in the Pool
・292 + 100 (new)
External Power
(Mar.24- connected to the central control room)
・Mar.12 - Venting started
・Mar.12 - Hydrogen explosion
・Mar.12 - Seawater injection to
reactor core
・Mar.25 - Fresh water injection to
reactor core
・Mar.31 - Fresh water spray by
concrete pump trucks
to spent fuel pool
・Apr. 7 - Injection of nitrogen to
the primary containment
vessel
10
1. Cool Down the Reactors
(Unit 2)
Damaged
Spent Fuel Pool Cooling System
Major Events
Possible damage of
the suppression chamber
Ministry of Defense
Recovered
Emergency Diesel Generator
Residual Heat Removal System
Fuel Bundle
・548
Spent Fuel in the Pool
・587 + 28 (new)
Injecting fresh water
or seawater
The fuel
pellets are
presumed
to be
melting
Damaged
（As of Apr 25th, 2011）
External Power
(Mar.26- connected to the central control room)
・Mar.13 - Venting started
・Mar.14 - Seawater injection to
reactor core
・Mar.15 - Sound of explosion
・Mar.20 - Seawater injection to spent
fuel pool (SFP)
・Mar.26 - Fresh water injection to
reactor core
・Mar.29 - Fresh water injection to
SFP
11
1. Cool
1.
CoolDown
Downthe
theReactors
Reactors
(Unit
(Unit 3)
3)
(As of 18:30 April 8th,
2011)
（As of Apr 25th, 2011）
Spray
Damaged
Spent Fuel Pool Cooling System
Injecting fresh water
or seawater
The fuel
pellets are
presumed
to be
melting
Major Events
Air Photo Service Inc (Myoko, Niigata Japan)
Damaged
Recovered
Emergency Diesel Generator
Residual Heat Removal System
Fuel Bundle
・548
Spent Fuel in the Pool
・514 + 52 (new)
External Power
(Mar.22- connected to the central control room)
・Mar.13 - Venting started
・Mar.13 - Seawater injection to
reactor core
・Mar.14 - Hydrogen explosion
・Mar.20 - Sprayed to spent fuel
pool (SFP) by Tokyo
Fire Department
・Mar.25 - Fresh water injection
to reactor core
・Mar.27 - Fresh water spray by
concrete pump trucks
to SFP
12
1. Cool Down the Reactors
2. (Unit
(Unit 4)
4)
(As of（As
18:30
April25t
8th,
2011)
h, 2011）
of Apr
Spray
Damaged
Spent Fuel Pool Cooling System
Fuel Bundle
・0
Spent Fuel in the Pool
・1331 + 204 (new)
No Fuel in Reactor Pressure Vessel
Major Events
Recovered
Air Photo Service Inc (Myoko, Niigata Japan)
External Power
(Mar.29- connected to the central control room)
・Mar.15 - Fire occurred
・Mar.16 - Fire occurred
・Mar.20 - Seawater spray by
Self- Defense
Forces to spent
fuel pool (SFP)
・Mar.25 - Seawater injection
to SFP
・Apr. 7 - Fresh water spray
by concrete pump
trucks to SFP
13
1. Cool Down the Reactors
(Unit 5&6)
（As of Apr 25th, 2011）
Fuel Bundle
・Unit5 : 548
Fuel Bundle
・Unit6 : 764
Spent Fuel in the Pool
・Unit 5 : 946 + 48 (new)
Spent Fuel in the Pool
・Unit 6: 876 + 64 (new)
Functioning
Spent
Spent Fuel
Fuel Pool
Pool Cooling
Cooling System
System
KYODO NEWS
Functioning
External Power [Unit 5]
Emergency Diesel Generator
ResidualHeat
HeatRemoval
RemovalSystem
System
Residual
Recovered
External Power [Unit 6]
(Mar.22- connected to the central control room)
14
2. Contain the Spread of Radioactive Substances
(sea, soil and atmosphere)
The Japanese Government and TEPCO are making the utmost efforts to prevent the dispersion
of flow-out radioactive contaminated water.
Artificial basin
Major Events
Locking in radioactive materials
by spraying synthetic resin
Unit 1
Unit 2
Suppression pool
water surge tank
Unit 3
Unit 4
Megafloat
Contaminated
water leak stopped
Condensate storage tank
・Mar. 27
Stagnant water on the basement
floor of the turbine of Unit2
and in the trenches found
to be highly contaminated
・Mar. 29
Water in the storage tank started to
be transferred to the surge tank,
which is the preparation for transfer
of stagnant water in the trenches.
・Apr. 1
Highly contaminated water
discovered leaking into the sea
・Apr. 6
Leak of contaminated water
into the sea was stopped
・Apr. 19
Transfer of stagnant water in the
trench of Unit 2 started
15
2. Contain the Spread of Radioactive Substances
(sea, soil and atmosphere)
Experts are making the utmost efforts to prevent dispersing radioactive substances
contained in dust, debris and vapor.
Spraying synthetic materials on the surface of the ground
and debris to prevent radioactive substances dispersion
TEPCO
16
Roadmap towards Restoration from the Accident
(announced by TEPCO on Apr.17)
Mar.11
Apr.17
Around 3 months
Around 6~9 months
Step 1
Target
Radiation dose
in steady decline
Step 2
Controlling release of
radioactive materials
(significant reduction of dose level)
Stable cooling
[Reactors]
- Resume heat exchange function
- [Unit 1,3] flood up to top of active fuel
- [Unit 2] Seal the damaged location
Stable cooling
[Spent Fuel Pools]
[Contaminated Water]
[Contaminated
Atmosphere/Soil]
- Enhance reliability of water injection
- Restore coolant circulation system
- [Unit 4] Install supporting structure
Secure storage place
- Prevention of outflow to the outside of the
site
Prevention of spread
Achieve cold shutdown
More stable cooling
- Keep sufficient level of water
by remote-control
- Resume heat exchange function
Decrease contaminated water
(decontamination and desalt)
Install reactor building cover
17
3. Rigorous and Intensive Monitoring
TEPCO monitors radioactivity levels every 10 minutes and releases the results
immediately. Radioactivity levels rose on March 15th, but have since fallen and
remain low.
Environmental Radioactivity Level
at the Fukushima Dai-ichi NPS
Monitoring posts and the readings at the
Fukushima Dai-ichi NPS
(μSv/h)
Unit 1~6
Near West Gate
21.0 μSv/h
（μSv/h）
Explosion in Unit2
12,000
Measurement point:
Main Gate (1.0km from Unit2)
or West Gate (1.1km from Unit2)
White smoke
from Unit3
4,000
2,000
Grayish smoke from Unit3
0
 Main Gate
53.0 μSv/h
（as of 10:00 April 25th, 2011）
TEPCO
18
0.40
0.3
0.30
14-Mar
15-Mar
16-Mar
17-Mar
18-Mar
19-Mar
20-Mar
21-Mar
22-Mar
23-Mar
24-Mar
25-Mar
26-Mar
27-Mar
28-Mar
29-Mar
30-Mar
31-Mar
1-Apr
2-Apr
3-Apr
4-Apr
0.40
μSv/hour
0.3
0.30
Tokyo
230km
0.00
Osaka
400km
0.1
0.10
14-Mar
15-Mar
16-Mar
17-Mar
18-Mar
19-Mar
20-Mar
21-Mar
22-Mar
23-Mar
24-Mar
25-Mar
26-Mar
27-Mar
28-Mar
29-Mar
30-Mar
31-Mar
1-Apr
2-Apr
3-Apr
4-Apr
14-Mar
15-Mar
16-Mar
17-Mar
18-Mar
19-Mar
20-Mar
21-Mar
22-Mar
23-Mar
24-Mar
25-Mar
26-Mar
27-Mar
28-Mar
29-Mar
30-Mar
31-Mar
1-Apr
2-Apr
3-Apr
4-Apr
5-Apr
6-Apr
7-Apr
Atmospheric Readings in
Tokyo, Osaka and Sapporo
(μSv/h)
0.40
(μSv/h)
μSv/hour
Max.
0.20
0.10
0.0
(μSv/h)
μSv/hour
0.3
0.30
0.2
0.2
0.20
0.1
0.1
0.10
Min.
MEXT
Sapporo
630km
Min.
Max.
Min.
0.0
0.00
Green box indicates
normal range of
radioactivity
Max.
0.2
0.20
Fukushima Dai-ichi
0.0
0.00
19
INES Rating on the Events in Fukushima Dai-ichi NPS
The Rating of the International Nuclear and Radiological Event Scale (INES) on
Fukushima Dai-ichi Nuclear Power Station (NPS), in temporary assessed as Level 7.
Chernobyl
[5.2 million TBq]
7
Major Accident
6
Serious Accident
5
Accident with Wide Consequences
4
Accident with Local Consequences
3
Serious Incident
2
Incident
1
Anomaly
0
No Safety Significance
Fukushima Dai-ichi
[0.37~0.63 million TBq]
Three Miles Island
*Level 7 : more than several tens of thousands TBq131I
*Level 6 : thousands to tens of thousands TBq131I
*Level 5 : hundreds to thousands TBq131I
20
C. Impact on Energy Supply/Demand
1. Impact on Energy Supply/Demand
21
1. Impact on Energy Supply/Demand in Japan
Tokyo Electric Power Company supplies electricity to an area with 42 million
people and 40% of Japan’s GDP, but lost 40% of its generation capacity after the
earthquake and tsunami.
We are making the utmost efforts to match supply and demand during the peak-load
summer on both the demand and supply side.
60 (GW)
52GW
(Mar.11)
Peak Demand
of the Month
Earthquake
(Mar.11)
50 GW
(Jul. 31)
50
Peak Demand
of the Month
40
30
33GW
(Mar.17)
31GW
(Mar.14)
29GW
(Mar.14)
20
10
Supply Capacity of TEPCO
0
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
22
D. Responsiveness to the World
1. Cooperation with International Organizations
2. Speedy Dissemination of Accurate Information
23
1. Cooperation with International Organizations
International Atomic Energy
Agency (IAEA)
The March 19 Joint Statement Confirmed
- No Restrictions on Travel to Japan 
International flight and maritime
operations can continue normally into and
out of Japan’s major airports and sea ports,
excluding those damaged by the tsunami.
International Maritime
Organization (IMO)

Screening for radiation of international
passengers from Japan is not considered
necessary at this time.
World Meteorological
Organization (WMO)

Currently available information indicates
that increased levels have been detected at
some airports, but these do not represent
any health risk.
International Civil Aviation
Organization (ICAO)
World Health Organization
(WHO)
Joint Statement from above Five Organizations
http://www2.icao.int/en/NewsRoom/Lists/News/Attachments/37/PIO.05.11.EN.pdf
24
2. Speedy Dissemination of Accurate Information
• Japan is committed to the speedy dissemination of accurate information.
• All necessary information are available below.
Japan’s Countermeasures
• 1.http://www.kantei.go.jp/foreign/incident/index.html
• 2.http://www.meti.go.jp/english/index.html
• 3.http://www.nisa.meti.go.jp/english/
Measurement of Radioactivity Level
•
•
•
•
1.http://www.mext.go.jp/english/topics/1305115.htm
2.http://www.nisa.meti.go.jp/english/
3.http://www.worldvillage.org/fia/kinkyu_english.php
4. http://www.tepco.co.jp/en/press/corp-com/release/index-e.html
Drinking Water Safety
• 1.http://www.mhlw.go.jp/english/topics/2011eq/index.html
• 2.http://www.waterworks.metro.tokyo.jp/press/shinsai22/press110324-02-1e.pdf
Food Safety
• 1.http://www.maff.go.jp/e/index.html
• 2.http://www.mhlw.go.jp/english/topics/2011eq/index.html
Ports and Airports Safety
• 1.http://www.mlit.go.jp/page/kanbo01_hy_001428.html
• 2.http://www.mlit.go.jp/koku/flyjapan_en/index.html
• 3.http://www.mlit.go.jp/page/kanbo01_hy_001411.html
25
The people of Japan
deeply appreciate
the sympathy
and assistance
pouring in
from people
all over the world.