We have some interesting comments on yesterday’s thread about the wonders of the INES. I wonder Fukushima results in a fundamental reform of the scale, with the IAEA taking on a role in vetting how states rank their nuclear disasters. Olli Heinonen thinks so, or at least that is how Pete Spots paraphrases him in the Christian Science Monitor.
Anyway, your daily fix from our friends at FEPC 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 9:30AM (EST), April 13, 2011
- Radiation Levels
- The concentration of radioactive nuclides from the seawater sampled at the screen device (installed to remove waste before the intake of seawater) of Unit 2 and sampled near the seawater discharge point (south side) of Fukushima Daiichi Nuclear Station were as follows:
Nuclides (half-life)
Concentration (Unit : Bq/cm3) Ratio Sampled at the screen of Unit 2 at 1:50PM on April 12 (a) Sampled at south side discharge point at 2:00PM on April 12 (b) Maximum Permissible Water Concentration (c) a / c b / c I-131 (8 days)
1.0 x 102 1.3 x 100 4.0 x 10-2 2,500 33 Cs-134 (2 years)
8.3 x 101 1.4 x 100 6.0 x 10-2 1,400 23 Cs-137 (30 years)
8.4 x 101 1.4 x 100 9.0 x 10-2 930 16
- At 4:00PM (JST) on April 13, radiation level at main gate (approximately 3,281 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 76 micro Sv/hour.
- At 4:00PM on April 13, radiation level at west gate (approximately 3,609 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 39.2 micro Sv/hour.
- Measurement results of environmental radioactivity level around Fukushima Nuclear Power Station announced at 1:00PM on April 13 are shown in the attached PDF file. English version is available at: http://www.mext.go.jp/english/radioactivity_level/detail/1304082.htm
- 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.
- Plant Parameters
Unit 1 Unit 2 Unit 3 Unit 4 Unit 5 Unit 6 pressure inside the reactor core (gauge pressure, MPa) 0.420 -0.016 -0.023 – 0.003 0.019 4/13 12:00PM
4/13 12:00PM
4/13 12:10PM
– 4/13 1:00PM
4/13 1:00PM
pressure inside the primary containment vessel (absolute pressure, MPaabs) 0.190 0.095 0.1036 – – – 4/13 12:00PM
4/13 12:00PM
4/13 12:10PM
– – – water level inside the reactor core (meter) *1 -1.6 -1.5 -1.75 – +1.59 +2.365 4/13 12:00PM
4/13 12:00PM
4/13 12:10PM
– 4/13 1:00PM
4/13 1:00PM
temperature of the reactor vessel measured at the water supply nozzle (degrees Fahrenheit) 400.1 *2
332.4 198.0 *2
– – – 4/13 12:00PM
4/13 12:00PM
4/13 12:10PM
– – – temperature of the spent fuel pool (degrees Fahrenheit) – 113 – – 95.2 73.4 – 4/13 12:00PM
– – 4/13 1:00PM
4/13 1:00PM
the temperature directly above the spent fuel pool by thermography measurement (degrees Fahrenheit) 78.8 – 138.2 98.6 – – 4/12 7:50AM
– 4/12 7:50AM
4/12 7:50AM
– – temperature directly above the primary containment vessel by thermography measurement (degrees Fahrenheit) 62.6 – 69.8 – – – 4/12 7:50AM
– 4/12 7:50AM
– – – temperature directly above the second containment building by thermography measurement (degrees Fahrenheit) – 82.4 – – – – – 4/12 7:50AM
– – – – Amount of water in total shot/injected to the spent fuel storage pool (tons) 90 359 – 374 5,238 1,816 – – as of 4/13 5:00PM
as of 4/13 5:00PM
as of 4/13 5:00PM
as of 4/13 5:00PM
– – *1: Minus figure means that water level is below the top of the fuel rods.
*2: This figure is under investigation.
- Fukushima Daiichi Unit 1 reactor
- As of 12:00PM on April 13, injection of nitrogen gas into the primary containment vessel to prevent an explosion by accumulated hydrogen gas continues.
- As of 12:00PM on April 13, the injection of freshwater into the reactor core continues.
- Fukushima Daiichi Unit 2 reactor
- At 7:35PM on April 12, transferring of the accumulated water at the trench (concrete tunnel which houses pipes and cables) outside the turbine building to the condenser commenced.
- At 1:15PM on April 13, TEPCO began to inject freshwater into the spent fuel pool, until 2:55PM.
- As of 12:00PM on April 13, the injection of freshwater into the reactor core continues.
- Fukushima Daiichi Unit 3 reactor
- As of 12:00PM on April 13, the injection of freshwater into the reactor core continues.
- Fukushima Daiichi Unit 4 reactor
- At 0:30AM on April 13, TEPCO began to shoot freshwater aimed at the spent fuel pool, with a specialized vehicle normally used for pumping concrete, until 6:57PM (approximately 195 tons in total).
- Fukushima Daiichi Common Spent Fuel Pool
- At 8:00AM on April 13, the temperature of the spent fuel pool: 84.2 degrees Fahrenheit.
- Others
- At 1:00PM on April 12 and at 10:00AM on April 13, TEPCO installed steel plates at the ocean side of the screen device of Unit 2 in order to contain the spread of discharged radioactive water.
- At 1:50PM on April 13, TEPCO installed a silt fence at the ocean side of the screen device of Unit 3 and 4 in order to contain the spread of discharged radioactive water.
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)