Outline of TEPCO Fukushima NPP accident

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Source: www.tepco.co.jp Fukushima Daini NPP Occurred at 14:46 on March 11, 2011 Magnitude:9.

1 ANSN Regional Workshop on Medical Response to Radiological Emergency Handling Complex Situations Outline of TEPCO Fukushima NPP accident Makoto Akashi, MD, PhD National Institute of Radiological Sciences The Great East Japan Earthquake Fukushima Daiichi NPP Epicenter Source: Fukushima Daini NPP Occurred at 14:46 on March 11, 2011 Magnitude:9.0 Mw Epicenter location: 38 1 N and E, and 24km in depth The height of tsunami which attacked Fukushima NPP was higher than 14 m (Max. 39 m at Taro town) Source: 1

Damages to Fukushima Daiichi NPP -All operating units were automatically shut down safely, when earthquake occurred. -Emergency D/Gs have worked properly until the Tsunami attack.

2 Damages to Fukushima Daiichi NPP -All operating units were automatically shut down safely, when earthquake occurred. -Emergency D/Gs have worked properly until the Tsunami attack. 1 Loss of Off-site Power due to the Earthquake Partially damaged Grid Line Tsunami (inundation height 14~15 m) Turbine Building Reactor Building About 25 M About 44 M Seawater level Seawater Pump Elevation: About 10 m D/G Emergency Diesel Generators 2Emergency Diesel Generator Inoperable due to the Tsunami 3Blackout & loss of all Cooling Function 2 Bare exposure of the fuels & damage to the fuel cladding Decreased water levels in the reactor pressure vessel (RPV) resulted in : Bare exposure of the fuels Damage to the fuel cladding, which is a metal tube that covers the fuel rods by the high temperatures Release of radionuclides 3

Reactor vessel control rod motors fuel core element control rod element Modified from Japan Atomic Energy Relations Organization 4 Release of radionuclides The earthquake and tsunami affected the

3 Reactor vessel control rod motors fuel core element control rod element Modified from Japan Atomic Energy Relations Organization 4 Release of radionuclides The earthquake and tsunami affected the Fukushima Daiichi NPP and caused serious damages to NPP, resulting in a large amount of radioactive materials being released into the environment. Te Bq (half life 78.2 h) I Bq (half life 8.0 d) Cs Bq (half life 2.1 y) Cs Bq (half life 30.0 y) As of June 6, 2011 Modification on October 20, 2011 ( by Nuclear and Industrial Safety) 5

Radionuclides released into the Atmosphere radionuclides half-life Unit 1 Unit 2 Unit 3 Total Xe-133 5.2 d 3.4 10 18 3.5 10 18 4.4 10 18 1.1 10 19 Cs-134 2.1 y 7.1 10 14 1.6 10 16 8.2 10 14 1.

4 Radionuclides released into the Atmosphere radionuclides half-life Unit 1 Unit 2 Unit 3 Total Xe d Cs y Cs y Sr d Sr y Ba d Te-127m d Te-129m 33.6 d Te-131m 30.0 h Te h Ru d Ru d Zr d Ce d Ce d Np d Pu y Pu y Pu y Pu y Y d Pr d Nd d Cm d I d I h I h I h Sb d Sb h Mo h Amouts of radionuclides released into the atmosphere were evaluated by the Nuclear and Industrial Safety Agency of Japan. Present status of NPPs in Japan On March 11, 2013, Operation 0 Under Suspension 50 As of September 15, Tomari out of 54 reactors were in operation. Kashiwazaki-Kariwa Higashidori 1 Takahama Mihama Tsuruga Shiga 1 2 Onagawa Fukushima Daiichi Ooi Fukushima Daiichi Fukushima Daini Shimane Genkai 1 2 Tokai No Sendai Ikata Hamaoka Non-operational incl. regular check-ups NPPs affected by earthquake and tsunami 7

Total deposition of Cs-134 and Cs-137 on the ground surface - Reflecting the results of the fourth airborne monitoring - ( As of December 16, 2011 ) Fukushima Daiichi NPP 134 Cs / 137 Cs (Bq/m 2 )

5 Total deposition of Cs-134 and Cs-137 on the ground surface - Reflecting the results of the fourth airborne monitoring - ( As of December 16, 2011 ) Fukushima Daiichi NPP 134 Cs / 137 Cs (Bq/m 2 ) Nov 5, 2011 Ministry of Education, Culture, Sports, Science and Technology and U.S. Department of Energy 8 Items Number of Measurement 0-50Bq/kg Bq/kg > 100Bq/kg Wheat and Barley Vegetables 7,744 7, Fruits 1,039 1, Pulse Mushrooms & NOT on the market 3,747 3, Wild edible plants 144 FY Regulation of food contamination Radioactivity levels of agricultural products in 17 prefectures Number of Measurement Vegetables 0-50 Bq/kg Bq/kg > 100 Bq/kg ,671 12, ,570 18, ,744 7, Reference : Ministry of Agriculture, Forestry and Fisheries website 100% 98% 96% 94% 92% 90% FY (April 2013 to July 2013) > 100 Bq / kg Bq / kg 0-50 Bq / kg Standard limits for Radioactive cesium Category Limit (Bq / kg) Drinking water 10 Milk 50 General Foods 100 Infant Foods 50 (Date of enforcement : April 1, 2012) 9

6 After NPP accident (at early phase) Inhalation Internal Contamination Intake of Contaminated Foods Nuclear Power Plant Accident Radiation Plume External Exposure Surface Fallout Food Chain Environmental Contamination 10 Dose rates in Fukushima Gunma μsv/h Saitama μsv/h Chiba μsv/h Tokyo μsv/h Kanagawa μsv/h ( As of September 16, 2013) 11

7 Dose rates in nature μsv / h Space 24 On space shuttle 7 Cosmic radiation during flights (Tokyo-San Fransisco) Sweden ー Before March 11, 2011 ー top of Mt. Fuji 0.15 Radon hot springs Tokyo 12 Medical Response at NIRS 13

8 Radiation Emergency Medical Assistance Team (REMAT) 2011 March 12 Fukushima Daiichi NPP 2011 March 12 8:10 am (17 hr after the earthquake) REMAT was dispatched from NIRS to Fukushima by a helicopter of JSDF 14 At off-site command center in Okuma-machi (from 12 to 15 March) No electricity No water supply Combined Disaster Damage to lifelines Internet Mobile phone Facsimile Telephone Satellite phone (2 lines) 15

9 Combined disaster High tide Flood Heavy snowfall Heavy rain Storm Release of Radiation Earthquake Disasters Ship accident Tsunami Volcano eruption Other natural phenomenon Fire or wildfire Explosion Others (train, plane) 16 Evacuation & Sheltering 52,277 people have left the Fukushima Prefecture (As of August 12, 2013, Fukushima Prefecture) 17

10 Evacuation & sheltering (1) March 11 14:46 Earthquake 21:23 Evacuation of residents within 3 km radius from Unit 1 of 1F NPP March 12 5:44 Evacuation within 10 km radius from 1F NPP 15:36 Hydrogen explosion at Unit 1 17:39 Evacuation within 10 km radius from 2F NPP 18:25 Evacuation within 20 km radius from 1F NPP March 13 Evacuation of patients at hospitals and facilities was arranged. Most of them were reallocated to outside hospitals. However, approximately 700 patients remained left within the 20 km zone. 0:47 Emergency evacuation was issued for patients in hospitals and facilities within the 20 km zone 11:01 Second hydrogen explosion at Unit 3 Eleven workers got injured. 18 Evacuation & sheltering (2) March 15 March 25 Indoor stay was directed to the residents from 20 to 30 km radius from 1F NPP 6:00 Explosion of Units 2 & 4 occurred Radiation level soared from 0.09 in am to μsv/hour in the evening in Fukushima 11:00 In-house evacuation from 20 km to 30 km from 1F NPP 15:00 Evacuation of all residents within 20 km zone was completed The Chief Cabinet Secretary asked voluntary evacuations for the residents within the area from 20 km to 30 km from 1F NPP 19

11 Contamination & Its Criteria for Screening 20 Changing the cut-off criteria for screening If the cut-off criteria for decontamination was 13, 000 cpm (as 131 I 40Bq/cm 2 ), many evacuees had to be decontaminated. However, At the shelter, evacuees were unable to ; Remove their clothes due to very low temperature Change their clothes due to no clean clothes Receive decontamination due to no water supply Therefore, Changing the criteria was necessitated : 13,000 cpm 100,000 cpm 21

First Responders to a Radiological Emergency Skin and clothing contamination criteria for

12 Is 100,000 cpm appropriate as cut-off value for public? 100,000 cpm 400 Bq/cm 2 of I-131 and 1 μsv/h at 10 cm IAEA EPR-First Responders 2006 Manual for First Responders to a Radiological Emergency Skin and clothing contamination criteria for determining if decontamination is warranted; > 1 μsv/h at 10 cm (ambient dose rate) 22 Medical problem & Contaminated Workers at TEPCO Fukushima Daiichi NPP 23

13 Activities of NIRS 24 Training courses for fire departments in Fukushima prefecture Fire Department Date No. of participants No. of sending experts Futaba Area Sep 21-22, Soma Area Oct 3-4, Iwaki City Oct 28, Fukushima City Nov 28-29, Aizu Area (Kitakata, Aizuwakamatsu, Minamiaizu) Feb 2, Shirakawa Area Feb 3, Date City Mar 16,

(March 14, 25 / May 30 / June 10, 20, 24 / June 1) 26 NIRS response to the disaster 500 450 3/24 I-131 concentration in tap

14 Screening of radiation for workers/residents at NIRS Checking body surface (As of February 22, 2013) TEPCO First responders 2,430 persons Governments Residents 331 persons Dose assessment / Decontamination Responders at NPP(JSDF 1, TEPCO 10) (March 14, 25 / May 30 / June 10, 20, 24 / June 1) 26 NIRS response to the disaster /24 I-131 concentration in tap water decreased to below regulation level & 3 workers were heavily contaminated No. of calls

Access for the website of NIRS 3/16 Radiation dose rate elevated sharply around the main gate of 1F & SDF helicopter sprayed seawater 3/24 I-131 concentration in tap water decreased to below

Accident: ~ 20,000 access per day Temporary house-visits operation Evacuees had a strong desire to return home temporarily to retrieve their belongings or check on their homes, farms, and businesses.

15 Access for the website of NIRS 3/16 Radiation dose rate elevated sharply around the main gate of 1F & SDF helicopter sprayed seawater 3/24 I-131 concentration in tap water decreased to below regulation level & 3 workers were heavily contaminated 3/25 Three heavily contaminated workers were transferred to NIRS 3/23 I-131 concentration of tap water exceeded the regulation level Before Accident: ~ 20,000 access per day Temporary house-visits operation Evacuees had a strong desire to return home temporarily to retrieve their belongings or check on their homes, farms, and businesses. 1. Allowed from May 10, Limited to 2 to 5 h to keep radiation exposure to 1 msv or lower 3. Only two persons per household 4. Not allowed for residents < 15 years old and senior citizens 5. Cannot not bring out food or farm animals except pets 6. Radiation surveys and medical care 29

Number of evacuees from restricted area Total about 78,200 people Katsurao-mura 300 Tamura city 600 20k m Minamisouma City

jp/b_menu/shingi/chousa/kaihatu/016/attach/ icsfiles/afieldfile/2011/04/18/1305143_1 Tomioka 16,000 Naraha 7700 30

16 Number of evacuees from restricted area Total about 78,200 people Katsurao-mura 300 Tamura city k m Minamisouma City 14,300 Namie town 19,600 Futaba 6,900 Ookuma 11,500 Kawauchi-mura icsfiles/afieldfile/2011/04/18/ _1 Tomioka 16,000 Naraha Flowchart of temporary house visit 20 km Restricted area Evacuation center Relay station Meeting place Meeting place Stay only 2 hours Survey member Safety manager 31

17 Summary 32 Summary (1) Radiation can not be seen, heard, smelt, or felt, & does not cause immediate symptoms. Public do not understand radiation and its effects. 33

18 Summary (2) There are no workers, operational staff, or emergency response personnel requiring treatment for radiation exposure or contamination with radioactive materials Basic education on radiation is essential for its use and also protection, since radiation is widely used in society 34 Summary (3) Basic education on radiation is essential for its use and also protection, since radiation is widely used in society Opportunity for obtaining basic knowledge of radiation is important in school 35

NUCLEAR PROBLEMS WITH THE JAPAN DISASTER. Yasuhiro Otomo, MD. PhD.

NUCLEAR PROBLEMS WITH THE JAPAN DISASTER Department of Acute Critical Care and Disaster Medicine, Tokyo Medical and Dental University Graduate School of Medicine Yasuhiro Otomo, MD. PhD. HUGE TRAGEDY AN