Nuclear Emergency Declared At 2 Plants In Japan 752
Hugh Pickens writes "CBC reports that Japan has declared a state of emergency and called for mass evacuations near two nuclear power plants following cooling systems failures that led to radiation escaping from a reactor at one location. The emergency declarations, which include five reactors at the two plants, followed Friday's 8.9-magnitude earthquake off the country's northeast coast. In a troubling announcement, Japan Nuclear and Industrial Safety Agency official Ryohei Shiomi said a monitoring device outside the plant detected radiation that is eight times higher than normal and an evacuation zone has been expanded from three kilometres around the plant to 10 kilometres."
Its worse and I reported that half an hour earlier (Score:3, Informative)
NHK (Score:5, Informative)
Since most foreign media just use NHK news, here is the link to their english website:
http://www3.nhk.or.jp/daily/english/index.html [nhk.or.jp]
I am in japan and following this very closely
discrepancy (Score:5, Informative)
There's a lot of misinformation flying around.
http://www.bbc.co.uk/news/world-asia-pacific-12721498 [bbc.co.uk] [bbc.co.uk] (watch the movie)
Steam was released on purpose.
Based on just this discrepancy between the BBC and the CBC articles, /. might be a bit careful on it's reporting right now...
Everyone's getting excited over the nuclear plants, and ignoring the thousands that are still are dying due to just water. Why is radiation so much scarier? Water kills faster. /rant.
Re:discrepancy (Score:5, Informative)
Re:So much for the safety of nuclear energy (Score:4, Informative)
Although I agree with your general assessment. In regard to dying from doing too much LSD, I think that is a quite low probability given its relatively high LD50 compared to what is usually taken. Information gleaned from an overview of the Wikipedia entry and its sources (along with Erowid) suggest no documented deaths linked to LSD usage alone.
Re:discrepancy (Score:4, Informative)
ie "27,000 liters of water, including water stored for firefighting, was being pumped into the reactor via makeshift pumps and other means in order to raise the water level above the reactor's nuclear fuel," at Fukushima Daiichi.
Its seems if they can get diesel-powered generators online, it might be ok, if not, the internal damage will add up fast.
Re:So much for the safety of nuclear energy (Score:5, Informative)
LSD is effectively non-toxic in humans. People occasionally do stupid things while on LSD that result in death, but keep in mind that people also do stupid things while excited, agitated, or depressed.
Explosion (Score:3, Informative)
NHK World is reporting serious emissions (Score:5, Informative)
The outer walls of the Reactor 1 building have partially blown off, leaving only what looks like a steel frame. NHK is saying that a sensor within 5km of the plant is detecting radiation levels approaching 1015 microsieverts - that is apparently a year's worth of radiation exposure each hour.
People in the danger zones are being told to cover faces with wet towels, avoid eating vegetables and other fresh foods, and refrain from drinking tap water. Things seem to be happening quickly.
Explosion (Score:4, Informative)
BBC just lost all credibility for me... (Score:4, Informative)
When they've burst out with the 88.000 (eighty-eight-thousand) people missing in Japan, which they've supposedly picked up from Kyodo news agency.
Which then got copy/pasted all over the internet by every damn blogger and news agency out there. So now, it gets parroted around like it is a fact. [m24digital.com]
It turns out... it was a typo. Or a mistranslation. Or a googling error [google.com] considering that some reports mention it as 110.000 missing.
BREAKING NEWS: Death toll from Japan quake rises to 110, 350 missing: police Note ... 200-300 bodies found in Sendai after quake, 88 others killed ...
See? Right there. "110, 350 missing"!
*headdesk*
And here I thought that one would actually have to know how to read if one wanted to be a BBC journalist.
FFS... 88000 people can't go "missing" in such a short time. It's technically impossible. Why?!
Well, besides the fact that 88000 people take up quite a lot of space and someone would pretty fucking soon notice them and proclaim them dead or found (identified or not) - you can't really know that there are 88000 people missing unless you can actually account for 88000 names. Or at least 88000 bodies.
And it takes a bit longer than 24 hours to compile a list of 88000 actual humans.
Let's say that it takes 5 minutes for a person to fill out a "missing persons" form, and for someone else to input that into a database.
If the reports were coming in non-stop from 100 locations that would make it 4400 minutes just to gather all the reports ( 88000 reports divided by 100 locations times 5 minutes i.e. (88000/100)*5 ).
That comes out to about 3 days of non-stop report gathering alone.
It would actually take about 10 times that, at least.
There simply was not enough time yet to gather that kind of actual data.
And again... If you know of 88000 actual people (Name, date of birth, address etc.) that are missing - just look for a really big pile of people somewhere. [youtube.com]
Pretty sure you'll find a lot of them there.
Well... unless there were aliens involved. Then all bets are off.
Except the one with the time it would take to compile a list of 88000 names and addresses.
There's video (Score:5, Informative)
How biosconcentration of radionuclides work (Score:2, Informative)
Biggest Japanese earthquake in 1400 years just happened too, its not like nuclear reactors are running around killing people yearly.
Actually, yes they are. The reason they are is that once a radioactive isotope is released into the environment it bio-concentrates in the food chain. If it is eventually eaten by a human it will continue to be a radiation emitter inside the body. Where it ends up inside the body depend on the element it analogues. For example, caesium (138 - I think) looks like iodine to the body - so the body deposits it in the thyroid gland. As the radionuclide emits radiation in that part of the body cancer begins to gestate expressing itself as full blown cancer at the end of the incubation period.
DOn't forget it's not just reactors that release radioactive isotopes, but the whole process. Chernobyl, Windscale and TMI are still killing people today and will go one killing people whenever a radioactive isotope from those accidents is ingested. Once the person dies and decays (or worse is cremated) the isotope is freed from the body and the process begins all over again until the radionuclide decays into it's daughter product.
Actual Information (Score:3, Informative)
Tokyo Electric Power Company is providing regular updates with real information:
http://www.tepco.co.jp/en/index-e.html [tepco.co.jp]
It appears the news services are reporting from a parallel universe where things are completely different.
Re:So much for the safety of nuclear energy (Score:5, Informative)
If you really want to know, here's the press releases from TEPCO [tepco.co.jp] which runs the plants. It's far more informative and far less alarmist than most of the reports going around. Yes, they are evacuating. Yes, there has been some unknown level of radiation leakage, but we don't know how bad it is just yet.
Those who want to review how the safety mechanisms of a BWR work should read this [wikipedia.org].
Why it exploded (Score:5, Informative)
It will take the media and Japan a while to circle around to what caused the explosion, so I'll explain it now.
The explosion you see in the videos aligns perfectly with the Fukushima Daiichi No.1 reactor building seen here [wikimedia.org] (forth square building from the left.)
The BBC has provided this incredible before/after photo [bbcimg.co.uk] where you can actually see the reactor building structure with the walls removed by the explosion: the metal framework is still intact.
The exact same thing happened with TMI-2 in 1979. The hydrogen burn occurred inside the containment dome. The Fukushima reactor doesn't have such a dome, so the hydrogen accumulated in the reactor building.
Re:Explosion (Score:4, Informative)
Video of the explosion and ensuing steam cloud: http://youtu.be/DHfR_wybvw0 [youtu.be]
Re:just dont get it (Score:1, Informative)
These reactors shut down within seconds of the earthquake, just like Three mile island. However, there's this dirty fact that the nuclear lobby don't tell you you much about: Even when a reactor is successfully shut down, it is still producing 100MW of energy for several days, due to the heat produced by decay of fission products with short half-life's that were produced while the reactor was still running. Therefore there's no "fail safe" mode - if you shut down a reactor and leave it without cooling, it will quickly melt down. It requires cooling for several days after to be safe.
Re:just dont get it (Score:4, Informative)
Because it's immaterial. They would need to shut it down perhaps a week before cooling was lost. A BWR that has been shut down will generate enough heat to violently self-destruct for at least a day or two, and enough heat to sustain internal damage perhaps for a week, IIRC.
What happens next (Score:5, Informative)
Hydrogen burn isn't a very energetic event, which is why the Reactor Building framework is still intact. This means the Reactor Vessel is still intact and bolted upright to the floor with the damaged core inside. The RV and the steel containment around it is a very robust container, much stronger than the framework of the building.
All cooling apparatus is gone. If the detonation didn't disable it the fire will. So total core melt is almost certain.
TMI-2 melted 50% of the core which pooled at the bottom of the RV. The RV did not rupture despite the intense heat. It is possible this RV may also not rupture, especially if any cooling can be applied to the outer surface. If so then widespread intense contamination may be avoided.
If the RV does rupture then we'll have molten corium pooling on the concrete floor uncovered before God and everyone. All bets are off at that point.
FYI the reactor is a GE Mark I BWR with steel containment. Details here [uiuc.edu](PDF). A very old, before-mandatory-concrete-containment-dome system.
Re:Thorium (Score:5, Informative)
Except you're completley missing what caused the damage. The damage you can see in the videos was not caused by the earthquake. It was caused by the reactor losing coolant, running too hot, producing hydrogen gas from the fuel essentially burning, and that gas exploding. As others have pointed out, this is exactly what happened at Three Mile Island, although TMI had an extra containment dome which the Japanese reactors lack, which is resulting in higher radiation leakage than TMI experienced.
Now, consider something lime a molten salt reactor. A modern reactor doesn't care if the coolant/heat exchanger cycle shuts down, as this earthquake appears to have caused. Heating up the coolant naturally slows down the reaction. Additionally, the coolant doesn't boil off, so the fuel is never exposed to oxygen or hydrogen. Combustion is impossible. At the very first step of the problem, the chain of events that leads to a loss of containment is cut. This is a monster of a quake, and yet it would have had no significant effect aside from the reactor safely reducing itself to minimal power (generating heat as quickly as it naturally dissipates) when the heat exchange cycle stopped.
Re:There's video (Score:4, Informative)
Re:What happens next (Score:4, Informative)
If the RV does rupture then we'll have molten corium pooling on the concrete floor uncovered before God and everyone. All bets are off at that point.
I'm hopeful that won't happen. The uranium fuel inside the reactor is a ceramic- you know, the type of material with very poor heat conduction. The steel RV has much better heat conduction, and flooding the primary containment (another pressure vessel between the RV and the outside rectangular building) should be a successful strategy.
Now, it may sound strange that the heat source in a massive heat engine has poor heat conduction, but it is the case. It takes a very specific geometry to both reach criticality (criticality = stable power generation in Nuke terms) and remove heat via the coolant.
Obviously there's not much in the way of coolant left, and the geometry is (ahem) 'suspect' at this point. However, the decay heat will continue to decrease as days go by, and little nuclear heat should be generated in a disorganized pile of molten ceramic. The bottom of the RV should hold.
(I am not a nuclear physicist, but I know a lot about making nuclear power)
Re:Enough is enough (Score:3, Informative)
He is not suggesting that there be no nuclear power stations, he is suggesting that it is better to operate plants that have better failure modes than water reactors like the one in this article.
Also, we should stop building coal plants. A little bit dangerous waste that we can see is in fact far better than enormous amounts of invisible waste.
Re:How biosconcentration of radionuclides work (Score:4, Informative)
You do know humans have radioactive isotopes in us without nuclear power or coal plants right?
You do know that 1 millionth of a gram of plutonium is a carcinogenic dose in the human body, it analogues iron when presented to a human metabolism, as high energy alpha emitter in the body it is extremely toxic. From World Nuclear Association's website on the Chernobyl disaster [world-nuclear.org] ;
5% of a 160 ton Nuclear reactor core that was about to be refueled - let's call it 100 tons, that's 5 tons of radioactive core into the atmosphere. At conservative estimates thats 5000,000,000,000 fatal doses. If we accept that an extremely conservative estimate of 1% of this makes it into the food chain via bio-accumulation and of that a conservative estimate of 1% of people are exposed and a conservative 1% of those exposed actually get some sort of fatal cancer that's 5,000,000 fatalities.
So please don't try to convince me that I can have pu-239 in me without a nuclear plant.
Radioactive decay has been occurring in humans since the first one was born in Africa.
Please don't be ridiculous, you know very well we are talking about radioactive isotope emissions from the nuclear industry. You focus on the reactors only instead of the entire industrial process over which radioactive isotope emission is inevitable. These are the types of radioactive isotopes that eventually end up bio-concentrating;
Those radioactive isotope emissions have been going on since the nuclear industry began, so which of them would you prefer to be decaying in your body.
Tens of thousands of humans die a year from natural Radon while deaths from nuclear accidents number in the single digits a year.
At TMI large amounts of contamination were released beyond Nuclear Industry assurances. The gamma radiation monitors on the top of the auxiliary building were not designed to measure such high concentrations and they went off the scale when the accident *began*, the release of contamination went on for several *days*. Estimates were based on thermoluscent dosimeters on the fence and Alpha and Beta emissions weren't even measured.
Because of the weather conditions it was known that emissions from TMI travelled a long way and were measured in Albany, NY. Joeseph Hendrie (former chairman of the NRC) was quoted (at the time) "We are operating almost totally in the in the blind, [Governor Thornburgh's] information is ambiguous, mine is non-existent and - I don't know - it's like a couple of blind men staggering aroun
Re:Dont mean to sound selfish (Score:5, Informative)
What could have happened that the reactor didn't scram?
No, all reactors properly shutdown with fail safes. The problem is, their reactors require active cooling which is something modern reactor designs specifically avoid for exactly these reasons. The problem is, just because the reactor has shutdown does mean the heat instantly goes away nor does it mean the core immediately stops creating heat. Their reactor designs require electric pumps to circulate coolant. When the reactor went down from the quake, their emergency generators started up. Those ran for about an hour until the tsunami reached the plant. The water, from what I've read, got into the generators and caused all of them to shutdown at the same time. The reactor's fail safes then fell back on a large battery bank. The batteries can't last for too long and from what I understand, power only a small subject of coolant pumps. As a result, the core temperature has continued to rise and a lot of water has evaporated. This is why they are working to get replacement batteries until they can get new generators online.
As a result of the heat, a lot of hydrogen formed and caused a massive explosion at one of the plants. Again, from what I've read, the explosion was external to the core's containment. As such, actual containment has not been lost. In order to address building coolant pressures from the rising temperatures, they've been forced to vent filtered yet radiative coolant.
Last I've heard, one worker has died from the explosion and a second was injured. Likewise, they are preparing to issue iodine to the surround population. Seems some of what has been vented is a radioactive form of iodine. Thusly, when the population ingests a non-radioactive source, its prevents absorption of yet additional iodine, including the radioactive iodine which has been released.
Re:Thorium (Score:4, Informative)
On nuclear physics..... (Score:4, Informative)
If you've got a question, son, just go ahead and ask it. There's no need to be a snarky little jackass.
Now, more folks know a large amount about nuclear power without being a D.O.P.E. (Doctor Of Pile Engineering), but apparently you can't fathom such a thing. I'll try to help you out.
The comment about not being a nuclear physicist relates to not being certain about nuclear power generation in a disorganized pile of uranium in the bottom of a reactor vessel.
What I do know, however, is that for a nuclear chain reaction to occur, you need neutrons splitting off of uranium, and then those neutrons need to cause fission of other uranium atoms.
However, these neutrons from a fission event are traveling at a substantial fraction of the speed of light, and at such speeds, they are unlikely to cause fission of another uranium atom. These neutrons need to be slowed to a 'thermal' state (near the kinetic energy of, say, water in an operating reactor) in order to cause the next fission event.
This is where the water comes in. The neutrons are slowed by the water to a thermal state, and in such a state, they are likely to cause the fission of another uranium atom, creating power and continuing the nuclear chain reaction.
When you've got a mass of molten uranium in the bottom of a pressure vessel, you don't have water in between the uranium atoms, so you can't slow down the neutrons to cause the next chain event.
Now, as to the heat conduction angle, normally the ratio of surface area to mass is high in normal geometry. A fuel pellet is about the size of a pencil eraser, a fuel rod is a stack of these in zircaloy cladding, and a fuel assembly is a cluster of these rods with space in between them (for the water to slow down the neutrons and carry heat away for power production.)
Now if you've got a molten pool of this stuff, the surface area vs the mass ratio is much lower. This means that heat removal (which is done with surface area) is degraded. As a consequence, the fuel heats up incredibly (until the decay heat falls off), but relatively little sensible heat is transferred to the steel reactor vessel- which can conduct heat away from the uranium pool at the bottom rapidly, especially if they flood the primary containment structure.
I have not, however, ran sophisticated computer simulations to these ends, nor am I qualified to perform a back of the envelope calculations to the same effect.
I am, however, intimately familiar with the normal and emergency operating parameters of a certain pressurized water reactor, and many of the physical principles are similar to that of the boiling water reactor in question. As such, I can compare the likely conditions in this reactor with the normal and emergency operating conditions in the reactor that I am familiar with, and make reasonably credible predictions- certainly moreso than you, or 95% of the stuff you've read so far.
But hey, there's no PHD in nuclear physics after my name. How could I possibly know anything relevant?