Busy day today; full text after the jump.
Update to Information Sheet Regarding the Tohoku Earthquake
The Federation of Electric Power Companies of Japan (FEPC) Washington DC Office
As of 11:00AM (EST), March 31, 2011
- Radiation Levels
o At 8:51AM (JST) on March 31, it was announced that radioactive nuclide I-131 was detected from the seawater sampled near the seawater discharge point (south side) of Fukushima Daiichi Nuclear Station at 1:55PM on March 30. The level of concentration was approximately 4,385 times higher than the maximum permissible water concentration set by the government.
o At 2:00PM on March 31, radiation level at main gate (approximately 3,281 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 157 micro Sv/hour.
o At 2:00PM on March 31, radiation level at west gate (approximately 3,609 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 99.9 micro Sv/hour.
o Measurement results of environmental radioactivity level around Fukushima Nuclear Power Station announced at 7:00PM on March 31 are shown in the attached PDF file. English version is available at: http://www.mext.go.jp/english/radioactivity_level/detail/1304082.htm
o For comparison, a human receives 2,400 micro Sv per year from natural radiation in the form of sunlight, radon, and other sources. One chest CT scan generates 6,900 micro Sv per scan.
- Fukushima Daiichi Unit 1 reactor
o At 8:00AM on March 31, pressure inside the reactor core: 0.329MPa.
o At 8:00AM on March 31, water level inside the reactor core: 1.65 meters below the top of the fuel rods.
o At 8:00AM on March 31, pressure inside the primary containment vessel: 0.21MPaabs.
o At 8:00AM on March 31, the temperature of the reactor vessel measured at the water supply nozzle: 480.9 degrees Fahrenheit
o At 9:20AM on March 31, transferring of the accumulated water at the trench (concrete tunnel which houses pipes and cables) outside the turbine building commenced, until 11:25AM. As a result, the water level at the trench was reduced from 0.14 meters to 1.14 meters below the top of the trench.
o At 1:03PM on March 31, TEPCO began to shoot freshwater aimed at the spent fuel pool, with a specialized vehicle normally used for pumping concrete.
o As of 3:00PM on March 31, the injection of freshwater into the reactor core continues.
o As of 3:00PM on March 31, preparation to recover and transfer the accumulated water at the turbine building continues.
- Fukushima Daiichi Unit 2 reactor
o As of 3:00PM on March 29, the water level at the trench was 1.04 meters below the top of the trench.
o At 8:00AM on March 31, the temperature of the spent fuel pool: 131 degrees Fahrenheit.
o At 8:00AM on March 31, pressure inside the reactor core: -0.016MPa.
o At 8:00AM on March 31, water level inside the reactor core: 1.5 meters below the top of the fuel rods.
o At 8:00AM on March 31, pressure inside the primary containment vessel: 0.11MPaabs.
o As of 3:00PM on March 31, the injection of freshwater into the reactor core continues.
o As of 3:00PM on March 31, approximately 96 tons of water in total has been injected into the spent fuel storage pool.
o As of 3:00PM on March 31, preparation to recover and transfer the accumulated water at the turbine building continues.
- Fukushima Daiichi Unit 3 reactor
o As of 3:00PM on March 29, the water level at the trench was 1.55 meters below the top of the trench.
o At 9:40AM on March 31, pressure inside the reactor core: 0.016MPa.
o At 9:40AM on March 31, water level inside the reactor core: 1.85 meters below the top of the fuel rods.
o At 9:40AM on March 31, pressure inside the primary containment vessel: 0.1066MPaabs.
o As of 3:00PM on March 31, the injection of freshwater into the reactor core continues.
o As of 3:00PM on March 31, approximately 4,697 tons of water in total has been shot to the spent fuel storage pool.
o As of 3:00PM on March 31, preparation to recover and transfer the accumulated water at the turbine building continues.
- Fukushima Daiichi Unit 4 reactor
o As of 3:00PM on March 31, approximately 1,098 tons of water in total has been shot to the spent fuel storage pool.
- Fukushima Daiichi Unit 5 reactor
o At 11:00AM on March 31, the temperature of the spent fuel pool: 86 degrees Fahrenheit.
- Fukushima Daiichi Unit 6 reactor
o At 11:00AM on March 31, the temperature of the spent fuel pool: 78.8 degrees Fahrenheit.
- Fukushima Daiichi Common Spent Fuel Pool
o At 8:20AM on March 30, the temperature of the spent fuel pool: 89.6 degrees Fahrenheit.
o As of 3:00PM on March 31, approximately 130 tons of water in total has been injected to the spent fuel storage pool.
Our official sources are:
- Office of The Prime Minister of Japan
- Nuclear and Industrial Safety Agency (NISA)
- Tokyo Electric Power Company (TEPCO) Press Releases
- Ministry of Education, Culture, Sports, Science and Technology (MEXT)