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Six-Month Timeline Since the Great East Japan Earthquake
[2011.10.03] Read in: 日本語 |

On March 11, 2011 a massive earthquake and tsunami struck the northeast of Japan. While the people of Japan responded calmly to the disaster and private-sector companies were quick to take part in recovery efforts, the government and the Tokyo Electric Power Company (TEPCO) were widely criticized for a sluggish and ineffective response. This timeline looks back on the half year since the disaster, with a focus on the government response to the nuclear disaster.

March 11–12

Date Fukushima Daiichi Nuclear Disaster and TEPCO Government Response Other Developments
March 11 The earthquake hits. The Unit 1, 2, and 3 reactors shut down automatically (Unit 4, 5, and 6 reactors had been shut down for regular maintenance). The tsunami knocks out the power supply for the Unit 1–4 reactors. 2:46 p.m. The Great East Japan Earthquake occurs.  
3:14 p.m. The government sets up an Emergency Disaster Response Headquarters.
5:00 p.m. Cabinet Secretary Edano Yukio states in a press conference that “no radiation has been leaked as of the current moment.”
7:03 p.m. A nuclear emergency situation is declared. A Nuclear Emergency Response Headquarters is set up in the Kantei (Prime Minister’s Official Residence).
7:42 p.m. Cabinet Secretary Edano states that there is “no need for residents near the Fukushima Daiichi Nuclear Power Station to immediately take any special measures.”
9:23 p.m. In a press conference, Prime Minister Kan Naoto calls for residents within a 3km radius of the Fukushima plant to evacuate and for residents within a 10km radius to remain indoors.
9:50 p.m. Cabinet Secretary Edano states in a press conference that the “evacuation instructions are a precautionary measure” and that “there is no present danger.”
March 12 Fuel rods in the Unit 1 reactor are partially exposed as water levels drop. A delay in venting steam from the reactor results in a hydrogen explosion in Unit 1 that blows away the upper part of the reactor building. Work begins to pump seawater into the Unit 1 reactor. 12:15 a.m. Prime Minister Kan and US President Barack Obama hold a meeting via telephone. Aftershock with a seismic intensity of Upper 6 hits Sakae, Nagano Prefecture.
5:44 a.m. Evacuation zone is extended to a 10km radius of the Fukushima Daiichi Nuclear Power Station.
7:11 a.m. Prime Minister Kan observes conditions at the Fukushima Daiichi Nuclear Power Station from a Ground Self-Defense Force helicopter.
9:55 a.m. The Nuclear and Industrial Safety Agency indicates that a meltdown may have occurred.
6:25 p.m. Evacuation instructions are extended to cover a 20km radius of the plant.
7:55 p.m. Prime Minister Kan issues instructions to inject seawater into the reactors (it later emerges that confusion reigned in the period leading up to this decision).

March 13–May 11

Date Fukushima Daiichi Nuclear Disaster and TEPCO Government Response Other Developments
March 13 In the Unit 3 reactor, the supply of cooling water stops following battery failure. The Japan Meteorological Agency amends its assessment of the severity of the earthquake from magnitude 8.8 to magnitude 9.0. An announcement is made that the number of Self-Defense Force troops dispatched to deal with the disaster will be increased to 100,000. Prime Minister Kan announces that rolling blackouts will begin on the following day. Cabinet Secretary Edano admits the risk of a hydrogen explosion in the Unit 3 reactor, but denies that a meltdown has occurred. US military forces stationed in Japan begin Operation Tomodachi to assist the relief effort in the north of Japan.
March 14 A hydrogen explosion at Unit 3 destroys the upper part of the reactor building. In Unit 2, fuel rods are completely exposed above water. After the hydrogen explosion in the Unit 3 reactor, Cabinet Secretary Edano announces that “the containment vessel remains intact” and denies the possibility that large quantities of radioactive materials have been dispersed. Mass confusion hits the Tokyo transportation system as a result of power outages implemented by TEPCO. The Nikkei closing average falls below ¥10,000. Services resume on the Sendai Subway.
March 15 An explosion is heard from Unit 2. Fire breaks out in the spent fuel pool in Unit 4. Prime Minister Kan visits the TEPCO head office in Tokyo. The government and TEPCO establish a Government-TEPCO Integrated Response Office. The Nikkei average falls below ¥9,000. Tōhoku Electric Power Company begins to implement rolling blackouts. An earthquake with a seismic intensity of Upper 6 hits eastern Shizuoka Prefecture, injuring 29 people.
March 16 White smoke billows from Unit 3. Plans to use three Ground Self-Defense Force helicopters to dump water on the reactor from the air are abandoned. In his morning press conference, Cabinet Secretary Edano indicates that the containment vessels at the Fukushima Daiichi Nuclear Station may have been damaged, but amends this statement in his afternoon press conference. The Emperor addresses the nation via a video message.
March 17 Two Ground Self-Defense Force helicopters drop 7.5 tons of water on Units 2 and 3. Self-Defense Force fire trucks pump water into the reactors from ground level. Prime Minister Kan and US President Obama hold a meeting via telephone. Sengoku Yoshito, former chief cabinet secretary, returns to the Kantei as deputy chief cabinet secretary. Relief supplies successfully landed at Sendai Airport thanks to assistance provided by the US Army.
March 18 Self-Defense Force fire trucks continue to spray water into the Unit 3 reactor. High-pressure pumps supplied by the US Army are also used. Law introduced to postpone municipal elections. Provisional assessment describes the situation in Units 1–3 as a “Level 5” event on the International Nuclear Event Scale. This is the same level as the 1979 Three Mile Island accident in the United States. Rolling blackouts are averted. Mizuho Bank’s computer network fails; this may have been caused by the overwhelming number of donations sent to people affected by the March 11 disaster.
March 19 Water is sprayed into the Unit 3 reactor using height-refraction water cannon fire engines belonging to the Tokyo Fire Department. Prime Minister Kan invites Liberal Democratic Party President Tanigaki Sadakazu to join the cabinet, but the offer is turned down.  
March 20 An external electrical power supply is connected to the Unit 2 reactor.   Nine days after the earthquake and tsunami, an 80-year-old woman and 16-year-old boy are rescued from a collapsed house.
March 21   Shipping restrictions are placed on spinach and kakina (a locally produced leaf vegetable) from Fukushima, Ibaraki, Tochigi, and Gunma Prefectures, and on raw milk from Fukushima Prefecture.  
March 22 Lighting is restored in the central control room at the Unit 3 reactor. All six reactors are now reconnected to electricity. Radioactive material is detected in seawater close to the water outlet of the Fukushima Daiichi Nuclear Power Station. Cabinet Secretary Edano insists that this level of radiation poses no damage to health, even if consumed continually for a year. The Nikkei average recovers to ¥9,500. Services resume on the Tōhoku Shinkansen bullet train line between Morioka and Shin-Aomori.
March 23   Restrictions are placed on the shipment and consumption of leafy vegetables and broccoli/cauliflower grown in Fukushima Prefecture. The Nuclear Safety Commission of Japan announces the results of calculations on the dispersal of radioactive materials made using the System for Prediction of Environmental Emergency Dose Information (SPEEDI).  
March 24 Lighting is restored in the central control room at the Unit 1 reactor. Three workers suffer radiation exposure when they step in puddles of water that have accumulated in the Unit 3 reactor building. The government announces the postponement of the spring ceremony for bestowing Japan’s Medals of Honor, scheduled for April 29.  
March 25 Pumping of fresh water into the reactor buildings begins. The government issues a request for residents to evacuate voluntarily from areas within 20 and 30 km of the plant.  
March 26      
March 27      
March 28      
March 29   The budget for fiscal 2011 is enacted.  
March 30 TEPCO announces that the Unit 1–4 reactors at Fukushima will be decommissioned. Prime Minister Kan and US President Obama hold a meeting via telephone. The Emperor and Empress visit an evacuee center in Tokyo.
March 31   Prime Minister Kan meets French President Nicolas Sarkozy at the Kantei. Services resume on the Yamagata Shinkansen bullet train line.
April 1 A chemical agent is sprayed to prevent the spread of radioactive materials. Prime Minister Kan announces the establishment of the Reconstruction Design Council. The government officially designates the March 11 disaster the “Great East Japan Earthquake.”  
April 2 Highly radioactive water is discovered to have leaked into the ocean from cracks in the Unit 2 reactor. Prime Minister Kan visits the disaster area in Rikuzentakata, Iwate Prefecture, and inspects the front-line base for responding to the nuclear disaster in Naraha, Fukushima Prefecture.  
April 3      
April 4 Water contaminated with low levels of radiation is released into the sea around the power station for the first time. The Japan Meteorological Agency announces its predictions for the diffusion of radioactive substances. Auctions at the fish market in Shiogama, Miyagi Prefecture take place for the first time since the March 11 disaster.
April 5   The government announces that it will establish the same provisional standard (2,000 becquerels of radioactive iodine) for seafood as is already in place for vegetables.  
April 6 The leaking of radioactive water into the sea from the Unit 2 reactor is blocked by pouring a fast-hardening glassy liquid containing sodium silicate into the cracks in the reactor. Cabinet Secretary Edano acknowledges the government failed to provide adequate explanation before releasing low-level radioactive water into the ocean from the Fukushima Daiichi Nuclear Power Station. Services restored along the entirety of the JR Kamaishi Line.
April 7 Nitrogen gas is injected into the containment vessel in the Unit 1 reactor. TEPCO President Shimizu Masataka is released from hospital.   Magnitude 7.1 aftershock strikes off the coast of Miyagi Prefecture. Services on the Tōhoku Shinkansen bullet train line resume between Morioka and Ichinoseki.
April 8 TEPCO announces that, in principle, it will not continue to implement planned blackouts in the future. First meeting of the committee in charge of distributing donations made to the relief and recovery effort. The Emperor and Empress visit a center set up in Saitama Prefecture to house evacuees from the nuclear disaster area in Fukushima.
April 9 Results of a study reveal that the tsunami that struck the Fukushima Daiichi Nuclear Power Station was 14 to 15 meters high.   The first evacuees begin moving into temporary housing in Rikuzentakata, Iwate Prefecture.
April 10   Prime Minister Kan observes conditions in Miyagi Prefecture. The first round of unified local elections are held, including elections to decide 12 prefectural governors. Ishihara Shintarō is elected Tokyo governor for the fourth time.
April 11 TEPCO President Shimizu Masataka travels to Fukushima Prefecture for the first time since the March 11 disaster, but Governor Satō Yūhei refuses to meet him. The Reconstruction Design Council is launched.  
April 12 Work begins to collect highly radioactive water. The status of the accident is raised to a Level 7 event on the International Nuclear Events Scale. Services resume on the Tōhoku Shinkansen bullet train line between Nasushiobara and Fukushima.
April 13 TEPCO confirms partial damage to the fuel rods in the Unit 4 spent fuel pool. The company announces its readiness to pay provisional compensation of ¥1 million per household.   Passenger flights partially resumed at Sendai Airport.
April 14 Silt fences are constructed in six places to control the water intake at the Unit 2 reactor. First meeting of the Reconstruction Design Council. The Emperor and Empress visit disaster areas in Asahi, Chiba Prefecture.
April 15 TEPCO announces it will be able to secure 52 million kilowatts of power by the end of July. Joint communiqué issued by G-20 Finance Ministers and Central Bank Governors expresses their “solidarity with the Japanese people” and their “readiness to provide any needed cooperation.”  
April 16      
April 17 TEPCO announces a schedule for the second stage of the disaster-response process; expects the situation make take six to nine months to be brought under control. Secretary of State Hillary Clinton visits Japan for meetings with Prime Minister Kan and Foreign Minister Matsumoto Takeaki.  
April 18      
April 19 Work begins on moving the highly radioactive water that has accumulated underground and in ditches inside the Unit 2 reactor. The Ministry of Education, Culture, Sports, Science and Technology establishes radiation limits for outdoor activities in schools. Activities are restricted at 13 school facilities in Fukushima Prefecture.  
April 20      
April 21 Highly radioactive debris is found near the Unit 3 reactor. Prime Minister Kan observes conditions in Fukushima Prefecture. Time magazine includes Sakurai Katsunobu, the mayor of Minamisōma, Fukushima Prefecture, and Takeshi Kanno, a doctor in Minamisanriku, Miyagi Prefecture, in its “2011 Time 100” list of influential people.
April 22 TEPCO President Shimizu Masataka visits the Fukushima Prefectural Government building for the first time since the March 11 disaster and personally apologizes to Governor Satō. All areas within a 20km radius of the Fukushima Daiichi Nuclear Power Station are designated a “restricted zone” that people are prohibited to enter. Places where the cumulative radiation dose may have reached 20 millisieverts per year are designated “planned evacuation areas.”  
April 23      
April 24      
April 25 TEPCO cuts executive compensation by half, and also reduces the annual salaries of managers by 25% and of general employees by 20%. First meeting of the Government-TEPCO Integrated Response Office.  
April 26 A radiation level of 1,120 millisieverts per hour is detected inside the Unit 1 reactor, the highest level within the Fukushima reactors thus far.   25th anniversary of the Chernobyl nuclear disaster.
April 27   The government enacts a law providing special tax breaks for victims of the March 11 disaster; it marks the first law enacted thus far to assist disaster victims. The Emperor and Empress visit disaster areas in Miyagi Prefecture.
April 28      
April 29 The quantity of water injected into the Unit 1 reactor is reduced owing to the risk of a hydrogen explosion.   The Tōhoku Shinkansen bullet train resumes full operations between Tokyo and Aomori for the first time in 49 days.
April 30   Japanese and US foreign ministers meet in Washington DC; the two countries agree to work together to counter widespread public concern about the safety of Japanese products.  
May 1      
May 2   The first supplementary budget is enacted. New car sales drop 47% compared to the same month the previous year following the impact of the March 11 disaster.
May 3   The government finally releases 5,000 pieces of data on predicted radiation levels, collected using the SPEEDI national network of detectors. This information was available earlier but was not released to the public. China eases restrictions on travel to Japan.
May 4      
May 5 Workers enter the Unit 1 reactor for the first time since the nuclear accident, installing duct-pipes for ventilation.    
May 6   Prime Minister Kan calls for a complete shutdown of the reactors at the Hamaoka Nuclear Power Station. The Emperor and Empress visit disaster areas in Iwate Prefecture.
May 7      
May 8      
May 9     Yielding to a request made by Prime Minister Kan, the Chūbu Electric Power Company decides to shut down all the reactors at its Hamaoka Nuclear Power Station.
May 10   The government postpones the decision on whether to join the Trans-Pacific Partnership free-trade agreement. Evacuees from within a 20km radius of the Fukushima nuclear plant, designated a “restricted zone,” are allowed temporary home visits.
May 11 Highly radioactive water is found to have leaked into the ocean from the intake canal near the Unit 3 reactor.   The Emperor and Empress visit disaster areas in Fukushima Prefecture.
  • [2011.10.03]
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