Latest information
2011-03-16 12:33: White clouds of billowing steam are emanating from Reactor number 3. It’s not clear on the source of the water vapour. It may be a broken water unit. Radiation around that plant has increase slightly. A helicopter is attempting to dump water on the building of Reactor 3 to cool it off or put out any fire that may be causing it. Efforts are underway to cool
Reactors 5 & 6 currently with positive result.
2011-03-16 9:56: A fire occurred last night on in the pressure control room of Reactor number 4 at the Fukushima Daiichi plant. The fire extinguished itself within half and hour. The level of radiation in the building made it too dangerous for firefighters to approach the fire while was burning. Radiation around the plant was seen to increase during the fire but fell back down afterwards. Currently the background radiation in the power plant around 400 milli-sieverts.
2011-03-15 22:34: A radioactive plume from the reactor grazed Tokyo today and raised the background radiation level to 23 times the normal level. Measurements in Kita-ku peaked at 218 micro-roentgens, above the normal level of 9 micro-roentgens. This is high but not dangerous. Levels dropped to 18 micro-roentgen by 22:00. This is not cause for panic. Some areas of the world have naturally higher background levels. From the 16th March a westerly breeze should return levels to normal. Once the problem with the plants have been resolved, levels should return to normal permanently.
2011-03-15 22:20: Reactors 5 & 6 at the Fukushima Plant 2 have begun to have begun to gradually rise in temperature. In addition, the radiation around the Fukushima Daiichi plant is around 400 milli-sieverts. To put this in perspective, 2 hours exposure to this would result in skin burns like a sun burn and nausea, follow by mild radiation sickness.
2011-03-15 22:10: Reactor 4 has suffered a hydrogen explosion and left a hole in the side of the containment building. Reactor 4 was offline before the earthquake on March 11 and was being used to store spent fuel rods in a settling pond in the building. Fuel rods in the settling pond, NOT the reactor are exposed. These spent fuel rods are placed here after they have been used up. There is not immediate danger of reactor core contaminates escaping. The fire was apparently caused by a fire in the settling pond igniting hydrogen. Residents within 30km of the plants are being warned to stay indoors. If you are within this zone you are advised to not dry your clothes outside. If you already have, do not bring them inside.
2011-03-15 9:21: Reactor 2 at the Fukushima Daiichi plant has triggered a hydrogen explosion in it’s containment building. Reactor 1, 2 and 3 now have suffered hydrogen explosions and damaged containment buildings.
2011-03-14 20:33: It’s just been revealed on NHK that the water level in reactor 2 at the Fukushima Daiichi power plant has dipped exposed 80cm of the fuel rods. Fuel rods need to be kept in water to keep the fuel cool and stop thermal damage. Fortunately (or rather by design) light water reactors need water not only for cooling but also to moderate the nuclear reaction (by slowing down neutrons), so the reactor core was not able heat up. However it could not dissipate the tremendous amount to heat already in the core from decay heat. The cause and results of this dip in water in the core are yet to be revealed.
2011-03-14 17:15: An alarming report from the NY Times newspaper reports that the USS Ronald Reagan crew passed through a plume of radioactive dust from the Daiichi reactors off the east coast of Japan. It’s not clear how far off coast. The apparently crew received a 1 month equivalent dose of radiation in an hour. That’s not high enough to cause sickness or long term health problems, but it hints that radioactive material is escaping from the site. Source
2011-03-14 14:59: It’s been reported that 11 people were injured in the explosion of containment building for Fukushima Daiichi reactor 3. Only a low amount of radiation is being observed outside the reactor area indicating that the reactor has not been breached. Pressure is still growing in the reactor and it is currently at 300 kilo-pascals. Work is being done to try and relieve pressure. If you are within the 20km exclusion zone please go indoors now. Close all window and stop air conditioners.
2011-03-14 11:59: There has been a hydrogen explosion at reactor 3 at the Fukushima Daiichi Plant. The roof and walls of the building have collapsed. A large amount of smoke has started being release from the containment building. The reactor is not breached or damaged, but pressure is still high in the core. All non-essential workers at the power plant are being evacuated. Residents of the area are urged to stay indoors. The 20km exclusion zone is still in effect. It is unknown if or how radioactive the smoke released it. Sources say radioactive leak unlikely. It’s possible that the hydrogen was slightly radioactive and the resultant steam from the explosion also likely radioactive since this hydrogen is generated from reactions in the core. The smoke would not be radioactive as it’s likely just debris from the building itself.
2011-03-14 09:37: Reactors 1 and 2 at Fukushima Daiichi have been be brought under control by cooling with sea water as of this morning. Radiation around the plant is down from 1000 microsievert to 400 microsievert an the south and 10 microsievert at the north side of the plant in the immediate area surrounding the reactor (the difference due to winds). The over pressure situation in reactor 3 still remains. The emergency team was able to open a valve they had been trying to access, but this did not release as much pressure as expected. The area is still evacuated around the plants.
2011-03-13 22:52: Seawater pump used for pumping in sea water to cool reactor 1 has stopped working. Emergency teams are looking for a workaround or a way to get water flowing again. Without seawater to cool the core, a meltdown could occur. A partial meltdown already appears to be occurring.
2011-03-12 22:15: Hydrogen buildup in reactor 3 of of the Fukushima Daiichi is causing a condition similar to conditions in reactor 1 before it blew up. Authorities are warning that an explosion could occur in reactor 3 and are battling to safely lower pressure and release hydrogen.
A nuclear emergency has been declared in the area surrounding the Fukushima nuclear power plants. A 20km Exclusion Zone is in effect around Fukushima Plant 1 (Daiichi) and a 10km exclusion zone around Fukushima Plant 2. The reactor is likely undergoing a partiak meltdown. TEPCO, which operates the reactors, is pumping seawater mixed with boric acid (a neutron absorber) into the reactor to cool it and inhibit criticality (the nuclear fission chain reaction).
Ceasium-137 a dangerous radioactive element has been detected near the plant. Residents of the area have been given potassium iodide to inhibit uptake of radioactive Iodine-131 (which collects in the thyroid). People living near the plants should follow officials instructions and listen the radio or TV. The current advisory for people living near the plant is to close your windows, keep the air conditioners off and stay indoors. There is also an advisory to cover mouth and nose with a mask, towel or handkerchief. A standard face mask offers little protection but is better than nothing. A wet handkerchief is preferred. A fine particle catching dust mask or gas mask will offer best protection.
*What about Tokyo?*
Tokyo is 300km south south west of Fukushima. World wind and weather patterns prevail from West to East as a rule of thumb (following the Earth’s rotation). Currently the winds are moving from West to East so Tokyo will not be effected my any immediate atmospheric radiation. We will keep you updated on the situation.
*Travel Information*
Rethink any travel plans you have to Fukushima. The area up north is experiencing a nuclear emergency and is already overwhelmed so please avoid added the pressure.
*Is a Chernobyl accident likely?*
No! A fast, uncontrolled nuclear reaction resulting in explosion is not possible with these type of light water reactors. A meltdown may result in the fuel assembly breaching the reactor and spilling into the already breached containment building. An over pressure situation in the reactor could also cause a steam explosion – though this is unlikely at present. There would be some significant damage from a steam explosion and significant local contamination from a reactor breaching meltdown. Don’t panic. Chernobyl was so devastating because of the resulting graphite fires that burn at unbelievable temperatures and pours thousands and tones of radioactive smoke into the air and surrounding areas.
*Background on the current crisis*
On March 11th 14:46pm Fukushima Daiichi Nuclear Power Plant was rocked by a Magnitude 8.9 earthquake. The nuclear reactors automatically shutdown. In an auto shutdown sequence control rods are inserted to stop criticality, the chain reaction that is at the heart of a nuclear power. After shutdown there is a remaining “decay heat” that needs to be cooled in order to safely “turn off” the reactor. This is achieved through heat sinks and a circulatory cooling unit. The emergency generators that power the cooling unit operated normally until they were damaged the tsunami just over 30 minutes later.
This left over decay heat can be in the order of 20-40 Mega Watts of heat energy. Initially the heat damaged the fuel assembly and caused it to distort. Continued uncontrolled heating could melt the assembly so the core material pools at the bottom of the reactor. It could also burn through the reactor’s bottom into containment facility. This is colloquially called a “meltdown”.
This has not happened, though there is a possibility that a partial meltdown is occurring. This likely means the metal casing of the fuel assembly has warped or started to balloon or liquefy. The fuel itself is actually a clay like material and will only melt a extremely high temperatures over 3500C which is not likely currently since cooling with seawater and boric acid is taking place at present.
On March 12th 15:36, Hydrogen leaking into the roof of the containment building for reactor 1 triggered an explosion which blew apart the containment unit. The reactor container remained intact. Potentially radioactive gas has been vented on the morning of March 13th.
On March 14th 11:00 hydrogen leaking in the containment building of reactor number 3 caused an explosion.
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