Local news in Japan is in full Nuclear Alert mode. They are in a loop warning everyone in the 20 to 30 KM zone to stay in side, don't use A/C (it is winter so it must be a civil defense script). Don't open windows, don't bring in the laundry. If you are at your office, stay there (if it is in the 20-30km zone. If you are in the 20km zone move away immediately. The news report is something straight out of a disaster movie. I have never seen this kind of extended broadcast. I think that the Prime Minister's message alerting the public to "a high likelihood of more releases of radioactive material" is allowing the press to kick into the civil defense mode.
It appears that the current worry are the burning spent fuel rods in the #4 reactor. These burning fuel rods are not in the containment vessel. These spent fuel rods are exposed and burning on the 4th floor of the #4 reactor.
I understood, according to BBC, that the spent fuel rod fire is now extinquished.
quote
The radiation reading at 0831 local time (2331 GMT) climbed to 8,217 microsieverts an hour from 1,941 about 40 minutes earlier, Tepco said. The annual legal limit is 1,000 microsieverts.
Click to play
AdvertisementJapan's PM says there is a 'very high' risk of further radiation leaks Higher radiation levels were recorded on Tuesday south of Fukushima, Kyodo news agency reported.
The French embassy said low-level radioactive wind could reach Tokyo within hours.
Mr Kan also said a fire had broken out at the plant's reactor 4. It now appears to have been put out
I still don't understand why they haven't extended the evac radius. Exposure is cumulative, meaning you can take a higher "dose" for a few minutes, than you can a lower "dose" for an extended period of time. It can be just as dangerous to get a small level exposure for 24 hrs straight as it is to get a big one for a few minutes.
Hope the firefighters were rotating in and out to minimize their own exposure---Chernobyl caused quite a few firefighter deaths.
just sayin..
[This message has been edited by maryjane (edited 03-14-2011).]
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11:18 PM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
TOKYO (Dow Jones)--Japanese Prime Minister Naoto Kan said Tuesday there's a high risk of elevated levels of radiation from a reactor at the Fukushima nuclear power plant that exploded earlier in the day, and urged people within 30 kilometers of the plant to stay indoors.
Authorities said an explosion at the No. 2 reactor at the Fukushima Daiichi nuclear power plant, located 160 miles northeast of Tokyo, appears to have caused damage. Some staff had been evacuated from the facility as radiation levels at the site rose sharply.
"Substantial amounts of radiation are leaking in the area," Kan said on television at 0200 GMT, urging people to remain calm. "We are making utmost efforts to prevent further explosions or the release of radioactive materials."
The Japanese Meteorological Agency dismissed a report that radioactive contamination from the plant could reach Tokyo in 10 hours.
An official at the agency said the fickleness of wind direction and the fact that there are many mountains between Fukushima and Tokyo make it unlikely that radioactivity from the nuclear plant would be found in Tokyo anytime soon.
Meanwhile, a separate explosion and fire took place Tuesday morning at the facility's No. 4 reactor. Tokyo Electric Power Co. (9501.TO), or TEPCO, the utility that runs the power plant, said the fire was probably from a spent fuel container and had damaged the reactor's ceiling, but said just before 0300 GMT that the fire had been extinguished.
Chief Cabinet Secretary Yukio Edano said radioactive steam had been emitted from the No. 4 reactor, and urged people living within a 20-kilometer radius of the plant to close their windows.
The Daiichi plant was brought down by Friday's massive earthquake, which automatically shuts off the power generation by the reactors, while the tsunami damaged generators that supply backup power. TEPCO has been struggling since then to safely shut down the cores at the facility's reactors.
Efforts to pump seawater into reactors No. 1, 2 and 3 in order to cool them were going smoothly, Edano said.
The International Atomic Energy Agency, the U.N. nuclear watchdog, said Tokyo had asked for expert assistance.
The key to preventing the crisis from turning into a full-blown disaster, experts say, is to protect the reactor's containment structure so that radiation is kept inside even after significant nuclear fission due to damage to the fuels. In the 1979 Three Mile Island incident in Pennsylvania, the containment structure remained intact, minimizing health effects on local residents.
Early Tuesday morning, an official from the Nuclear Safety Agency said the suppression pool at the No. 2 reactor, which converts steam from the reactor into water, could have sustained some damage.
In a separate briefing, a TEPCO official said the utility had no information showing damage to the containment vessel. But radiation levels rose to their highest Tuesday since the crisis began Friday.
National broadcaster NHK said the radiation level at the plant reached 8,217 micro sieverts an hour, which is at least eight times the amount recommended for an individual in a year. The number later fell back to around 2,400 micro sieverts, NHK said.
Kyodo News Agency reported that radiation 400 times the legal limit had been measured near the plant's No. 3 reactor.
TEPCO said it was evacuating an undisclosed number of workers from the plant who were not involved in containment efforts. It said it initially left a team of 50 employees to deal with the crisis, but that an unknown number of those have evacuated.
Kyodo quoted a TEPCO official as saying there was a possibility that there had been some melting of the rods that hold the nuclear material, a sign of a worsening situation that could require more drastic steps.
A Nuclear Safety Agency official, speaking to reporters informally, stressed that all of the information on the state of the plant is tentative at present due to the inability to inspect the reactor because of the dangers from the radiation, leaving operators to rely on pressure gauges and other instruments to make their best estimate of what's happening. He said that some of the data offered contradictory indications of what was actually taking place.
-By Kazuhiro Shimamura, Dow Jones Newswires; 81-3-6269-2785; kazuhiro.shimamura@dowjones.com
One thing that strikes me as odd is even when higher levels of radiation are now being detected, and a full on meltdown might occur, UN officials are saying that the risk to the public is quite miniscule. Isn't the same organization that blames every other form of pollution for every human ill?
[This message has been edited by loafer87gt (edited 03-15-2011).]
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12:11 AM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
One thing that strikes me as odd is even when higher levels of radiation are now being detected, and a full on meltdown might occur, UN officials are saying that the risk to the public is quite miniscule. Isn't the same organization that blames every other form of pollution for every human ill?
In other news, Japan now is saying it is unlikely able to comply to the Kyoto agreement, and might end up paying the UN over $500 million to cover the extra pollution credits now that their reactors are down and they will become more reliant on fossil fuels. I'm sure the UN, this is like winning the lottery.
fukushima I -reactor 4 : 2 8m² wide holes in the reactor hull , water in the pool for old reactor rods is boiling fukushima I - reactor 5,6 : possible cooling failure fukushima II all 4 reactors are venting steam to lower the inner pressure
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05:15 AM
rinselberg Member
Posts: 16118 From: Sunnyvale, CA (USA) Registered: Mar 2010
Japan's nuclear safety agency has said there are two holes of 8 sq m (86 sq feet) in a wall of the outer building of the number 4 reactor after an explosion there, Reuters reports.
It sounds like these holes are only in the outer building, not the reactor hull or containment structure.
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05:30 AM
PFF
System Bot
Raydar Member
Posts: 40957 From: Carrollton GA. Out in the... country. Registered: Oct 1999
Ok... So now they have 6 reactors with failed cooling... 4 in Meltdown mode and 2 coming.... At least 1 containment system that is questionable... Yea it sounds like they have it all under control!
In other news, Japan now is saying it is unlikely able to comply to the Kyoto agreement, and might end up paying the UN over $500 million to cover the extra pollution credits now that their reactors are down and they will become more reliant on fossil fuels. I'm sure the UN, this is like winning the lottery.
One thing that strikes me as odd is even when higher levels of radiation are now being detected, and a full on meltdown might occur, UN officials are saying that the risk to the public is quite miniscule. Isn't the same organization that blames every other form of pollution for every human ill?
That would probably be because, quite in contrast to most people and news sources, they know what they are talking about. A nuclear reactor cant become a nuclear bomb, nor would a 'meltdown' be the end of the world. Worst case scenario, a complete 'meltdown' wouldnt neccessarially result in the breachment of the containment vessel, and even if it did, the material would still be contained and its not going to explode high into the atmisphere. A steam explosion combined with an event with the fuel could have bad concequences, and there are other possiblities, but the reality of the situation is we arent going to die tomorrow, which is what we have been hearing every day since this started.
This is not a good situation, not by any means, but all you hear is fabricated bullshit from every angle from either people with an agenda, or attention hungry news whores.
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08:06 AM
phonedawgz Member
Posts: 17091 From: Green Bay, WI USA Registered: Dec 2009
Considering the trouble appears to be coming from the spent fuel pools it makes one wonder if that will drive a decision to change the US policy regarding spend fuel.
Note to alarmists - The US has a policy that spent fuel rods are to be kept at the nuclear power plants that they consumed at. This has been since Carter was President.
Operating the existing nuclear power plants are the least expensive way to generate a fuel supplied power plant. The cost is less than $0.03 / kwh.
Non-partisan non-political cite, please...
------------------ Bring back civility and decorum!
It's possible to understand someone's point of view without accepting it. It's possible to disagree with someone without being rude and nasty about it. Sure it's hard, but nothing worth doing is ever easy, is it?
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08:23 AM
phonedawgz Member
Posts: 17091 From: Green Bay, WI USA Registered: Dec 2009
One thing that strikes me as odd is even when higher levels of radiation are now being detected, and a full on meltdown might occur, UN officials are saying that the risk to the public is quite miniscule. Isn't the same organization that blames every other form of pollution for every human ill?
quote
Originally posted by Dennis_6 Shows their true colors nicely.
Let's try to keep politics out of this, please, it only serves to provide triggers to send the thread off into uncivil land of name calling and bickering... This subject is too important to the world, let alone us, to do that to it.
------------------ Bring back civility and decorum!
It's possible to understand someone's point of view without accepting it. It's possible to disagree with someone without being rude and nasty about it. Sure it's hard, but nothing worth doing is ever easy, is it?
Thanks for the link. Though incomplete (it doesn't have construction/decommissioning/waste storage costs in the total, for instance) it is interesting. Projected costs for decommissioning the local nuke plant, will be over 30 Billion in 1985 dollars, but luckily the taxpayers are footing the bill for storage of the waste for the next quarter million years. We got rammed down our throats a hefty rate increase of 15% when the nuke plant was brought online, which doesn't include the aforementioned "off the books" costs.
Day to day operating costs are quite a bit different than true end to end costs. And then there's the slight problem with having to import our nuclear fuel from Russia, a nation with a proven track record of using its energy exports for political leverage.
Edit to clarify a grammatical misconstruction which made it appear that I said something which I did not mean to say.
------------------ Bring back civility and decorum!
It's possible to understand someone's point of view without accepting it. It's possible to disagree with someone without being rude and nasty about it. Sure it's hard, but nothing worth doing is ever easy, is it?
[This message has been edited by JazzMan (edited 03-15-2011).]
Considering the trouble appears to be coming from the spent fuel pools it makes one wonder if that will drive a decision to change the US policy regarding spend fuel.
Note to alarmists - The US has a policy that spent fuel rods are to be kept at the nuclear power plants that they consumed at. This has been since Carter was President.
That policy extends industry and material wide. All hazardous pollution, regardless of type, are/is the property and responsibility of the entity that created it--forever. It can be stored elsewhere, if approved by the proper oversight agency, but it is still the responsibility of whoever created it.
What is really F*d up to me here, Japan is in the middle of the largest disaster they have ever seen, and they are worried about a crappy agreement.
I'd say that there is a time and a place to be worried about agreements, this is not one of them.
Brad
Not sure if you read the article or not but the one making the comments about the agreement is an analyst working for a company headquartered in Paris.
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08:48 AM
phonedawgz Member
Posts: 17091 From: Green Bay, WI USA Registered: Dec 2009
That policy extends industry and material wide. All hazardous pollution, regardless of type, are/is the property and responsibility of the entity that created it--forever. It can be stored elsewhere, if approved by the proper oversight agency, but it is still the responsibility of whoever created it.
No
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10:06 AM
phonedawgz Member
Posts: 17091 From: Green Bay, WI USA Registered: Dec 2009
Thanks for the link. Though incomplete (it doesn't have construction/decommissioning/waste storage costs in the total, for instance) it is interesting. Projected costs for decommissioning the local nuke plant, for which we got rammed down our throats a hefty rate increase of 15% when it was brought online, will be over 30 Billion in 1985 dollars, but luckily the taxpayers are footing the bill for storage of the waste for the next quarter million years.
Day to day operating costs are quite a bit different than true end to end costs. And then there's the slight problem with having to import our nuclear fuel from Russia, a nation with a proven track record of using its energy exports for political leverage.
So you are saying the costs to decommission the plants are already paid for. That's good.
So you are saying the costs to decommission the plants are already paid for. That's good.
You misconstrued what I wrote, I apologize for not writing more clearly. I'll go back and fix it to make it more clear, but no, the decommissioning costs were not included in the rate we're paying, nor is the waste disposal cost and long-term storage cost.
------------------ Bring back civility and decorum!
It's possible to understand someone's point of view without accepting it. It's possible to disagree with someone without being rude and nasty about it. Sure it's hard, but nothing worth doing is ever easy, is it?
To add, I think that all end to end costs of any given generating technology should be paid for by ratepayers alone, that ratepayers should be free to and in fact required to choose what form of generation they want their power from, with the only exception being that subsidies should be used to encourage development of generation technologies that are specifically non-importable. For instance, wind, solar, geothermal, wave, hydro, Peltier, tidal, nuclear fusion, nuclear thorium, are all existing or potential technologies whose fuel or source cannot be imported. Fossil and nuclear fission can be imported and therefor should get no subsidies because anything that can be imported gives source nations leverage over us. The intent of subsidies is to foster energy independence, because IMHO lack of energy independence has the potential to end this nation's existence.
------------------ Bring back civility and decorum!
It's possible to understand someone's point of view without accepting it. It's possible to disagree with someone without being rude and nasty about it. Sure it's hard, but nothing worth doing is ever easy, is it?
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11:00 AM
phonedawgz Member
Posts: 17091 From: Green Bay, WI USA Registered: Dec 2009
So I take it you are hanging your hat on IF the can be imported, not ARE they imported so it better matches your predetermined choice of energy sources.
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11:11 AM
RandomTask Member
Posts: 4540 From: Alexandria, VA Registered: Apr 2005
You guys need to stop getting your information from news agencies that would want nothing more but for you to be glued to them for more information. Take time to read this;
Along with reliable sources such as the IAEA and WNN updates, there is an incredible amount of misinformation and hyperbole flying around the internet and media right now about the Fukushima nuclear reactor situation. In the BNC post Discussion Thread – Japanese nuclear reactors and the 11 March 2011 earthquake (and in the many comments that attend the top post), a lot of technical detail is provided, as well as regular updates. But what about a layman’s summary? How do most people get a grasp on what is happening, why, and what the consequences will be?
Below I reproduce a summary on the situation prepared by Dr Josef Oehmen, a research scientist at MIT, in Boston. He is a PhD Scientist, whose father has extensive experience in Germany’s nuclear industry. This was first posted by Jason Morgan earlier this evening, and he has kindly allowed me to reproduce it here. I think it is very important that this information be widely understood.
Please also take the time to read this: An informed public is key to acceptance of nuclear energy — it was never more relevant than now.
We will have to cover some fundamentals, before we get into what is going on.
Construction of the Fukushima nuclear power plants
The plants at Fukushima are Boiling Water Reactors (BWR for short). A BWR produces electricity by boiling water, and spinning a a turbine with that steam. The nuclear fuel heats water, the water boils and creates steam, the steam then drives turbines that create the electricity, and the steam is then cooled and condensed back to water, and the water returns to be heated by the nuclear fuel. The reactor operates at about 285 °C.
The nuclear fuel is uranium oxide. Uranium oxide is a ceramic with a very high melting point of about 2800 °C. The fuel is manufactured in pellets (cylinders that are about 1 cm tall and 1 com in diameter). These pellets are then put into a long tube made of Zircaloy (an alloy of zirconium) with a failure temperature of 1200 °C (caused by the auto-catalytic oxidation of water), and sealed tight. This tube is called a fuel rod. These fuel rods are then put together to form assemblies, of which several hundred make up the reactor core.
The solid fuel pellet (a ceramic oxide matrix) is the first barrier that retains many of the radioactive fission products produced by the fission process. The Zircaloy casing is the second barrier to release that separates the radioactive fuel from the rest of the reactor.
The core is then placed in the pressure vessel. The pressure vessel is a thick steel vessel that operates at a pressure of about 7 MPa (~1000 psi), and is designed to withstand the high pressures that may occur during an accident. The pressure vessel is the third barrier to radioactive material release.
The entire primary loop of the nuclear reactor – the pressure vessel, pipes, and pumps that contain the coolant (water) – are housed in the containment structure. This structure is the fourth barrier to radioactive material release. The containment structure is a hermetically (air tight) sealed, very thick structure made of steel and concrete. This structure is designed, built and tested for one single purpose: To contain, indefinitely, a complete core meltdown. To aid in this purpose, a large, thick concrete structure is poured around the containment structure and is referred to as the secondary containment.
Both the main containment structure and the secondary containment structure are housed in the reactor building. The reactor building is an outer shell that is supposed to keep the weather out, but nothing in. (this is the part that was damaged in the explosions, but more to that later).
Fundamentals of nuclear reactions
The uranium fuel generates heat by neutron-induced nuclear fission. Uranium atoms are split into lighter atoms (aka fission products). This process generates heat and more neutrons (one of the particles that forms an atom). When one of these neutrons hits another uranium atom, that atom can split, generating more neutrons and so on. That is called the nuclear chain reaction. During normal, full-power operation, the neutron population in a core is stable (remains the same) and the reactor is in a critical state.
It is worth mentioning at this point that the nuclear fuel in a reactor can never cause a nuclear explosion like a nuclear bomb. At Chernobyl, the explosion was caused by excessive pressure buildup, hydrogen explosion and rupture of all structures, propelling molten core material into the environment. Note that Chernobyl did not have a containment structure as a barrier to the environment. Why that did not and will not happen in Japan, is discussed further below.
In order to control the nuclear chain reaction, the reactor operators use control rods. The control rods are made of boron which absorbs neutrons. During normal operation in a BWR, the control rods are used to maintain the chain reaction at a critical state. The control rods are also used to shut the reactor down from 100% power to about 7% power (residual or decay heat).
The residual heat is caused from the radioactive decay of fission products. Radioactive decay is the process by which the fission products stabilize themselves by emitting energy in the form of small particles (alpha, beta, gamma, neutron, etc.). There is a multitude of fission products that are produced in a reactor, including cesium and iodine. This residual heat decreases over time after the reactor is shutdown, and must be removed by cooling systems to prevent the fuel rod from overheating and failing as a barrier to radioactive release. Maintaining enough cooling to remove the decay heat in the reactor is the main challenge in the affected reactors in Japan right now.
It is important to note that many of these fission products decay (produce heat) extremely quickly, and become harmless by the time you spell “R-A-D-I-O-N-U-C-L-I-D-E.” Others decay more slowly, like some cesium, iodine, strontium, and argon.
What happened at Fukushima (as of March 12, 2011)
The following is a summary of the main facts. The earthquake that hit Japan was several times more powerful than the worst earthquake the nuclear power plant was built for (the Richter scale works logarithmically; for example the difference between an 8.2 and the 8.9 that happened is 5 times, not 0.7).
When the earthquake hit, the nuclear reactors all automatically shutdown. Within seconds after the earthquake started, the control rods had been inserted into the core and the nuclear chain reaction stopped. At this point, the cooling system has to carry away the residual heat, about 7% of the full power heat load under normal operating conditions.
The earthquake destroyed the external power supply of the nuclear reactor. This is a challenging accident for a nuclear power plant, and is referred to as a “loss of offsite power.” The reactor and its backup systems are designed to handle this type of accident by including backup power systems to keep the coolant pumps working. Furthermore, since the power plant had been shut down, it cannot produce any electricity by itself.
For the first hour, the first set of multiple emergency diesel power generators started and provided the electricity that was needed. However, when the tsunami arrived (a very rare and larger than anticipated tsunami) it flooded the diesel generators, causing them to fail.
One of the fundamental tenets of nuclear power plant design is “Defense in Depth.” This approach leads engineers to design a plant that can withstand severe catastrophes, even when several systems fail. A large tsunami that disables all the diesel generators at once is such a scenario, but the tsunami of March 11th was beyond all expectations. To mitigate such an event, engineers designed an extra line of defense by putting everything into the containment structure (see above), that is designed to contain everything inside the structure.
When the diesel generators failed after the tsunami, the reactor operators switched to emergency battery power. The batteries were designed as one of the backup systems to provide power for cooling the core for 8 hours. And they did.
After 8 hours, the batteries ran out, and the residual heat could not be carried away any more. At this point the plant operators begin to follow emergency procedures that are in place for a “loss of cooling event.” These are procedural steps following the “Depth in Defense” approach. All of this, however shocking it seems to us, is part of the day-to-day training you go through as an operator.
At this time people started talking about the possibility of core meltdown, because if cooling cannot be restored, the core will eventually melt (after several days), and will likely be contained in the containment. Note that the term “meltdown” has a vague definition. “Fuel failure” is a better term to describe the failure of the fuel rod barrier (Zircaloy). This will occur before the fuel melts, and results from mechanical, chemical, or thermal failures (too much pressure, too much oxidation, or too hot).
However, melting was a long ways from happening and at this time, the primary goal was to manage the core while it was heating up, while ensuring that the fuel cladding remain intact and operational for as long as possible.
Because cooling the core is a priority, the reactor has a number of independent and diverse cooling systems (the reactor water cleanup system, the decay heat removal, the reactor core isolating cooling, the standby liquid cooling system, and others that make up the emergency core cooling system). Which one(s) failed when or did not fail is not clear at this point in time.
Since the operators lost most of their cooling capabilities due to the loss of power, they had to use whatever cooling system capacity they had to get rid of as much heat as possible. But as long as the heat production exceeds the heat removal capacity, the pressure starts increasing as more water boils into steam. The priority now is to maintain the integrity of the fuel rods by keeping the temperature below 1200°C, as well as keeping the pressure at a manageable level. In order to maintain the pressure of the system at a manageable level, steam (and other gases present in the reactor) have to be released from time to time. This process is important during an accident so the pressure does not exceed what the components can handle, so the reactor pressure vessel and the containment structure are designed with several pressure relief valves. So to protect the integrity of the vessel and containment, the operators started venting steam from time to time to control the pressure.
As mentioned previously, steam and other gases are vented. Some of these gases are radioactive fission products, but they exist in small quantities. Therefore, when the operators started venting the system, some radioactive gases were released to the environment in a controlled manner (ie in small quantities through filters and scrubbers). While some of these gases are radioactive, they did not pose a significant risk to public safety to even the workers on site. This procedure is justified as its consequences are very low, especially when compared to the potential consequences of not venting and risking the containment structures’ integrity.
During this time, mobile generators were transported to the site and some power was restored. However, more water was boiling off and being vented than was being added to the reactor, thus decreasing the cooling ability of the remaining cooling systems. At some stage during this venting process, the water level may have dropped below the top of the fuel rods. Regardless, the temperature of some of the fuel rod cladding exceeded 1200 °C, initiating a reaction between the Zircaloy and water. This oxidizing reaction produces hydrogen gas, which mixes with the gas-steam mixture being vented. This is a known and anticipated process, but the amount of hydrogen gas produced was unknown because the operators didn’t know the exact temperature of the fuel rods or the water level. Since hydrogen gas is extremely combustible, when enough hydrogen gas is mixed with air, it reacts with oxygen. If there is enough hydrogen gas, it will react rapidly, producing an explosion. At some point during the venting process enough hydrogen gas built up inside the containment (there is no air in the containment), so when it was vented to the air an explosion occurred. The explosion took place outside of the containment, but inside and around the reactor building (which has no safety function). Note that a subsequent and similar explosion occurred at the Unit 3 reactor. This explosion destroyed the top and some of the sides of the reactor building, but did not damage the containment structure or the pressure vessel. While this was not an anticipated event, it happened outside the containment and did not pose a risk to the plant’s safety structures.
Since some of the fuel rod cladding exceeded 1200 °C, some fuel damage occurred. The nuclear material itself was still intact, but the surrounding Zircaloy shell had started failing. At this time, some of the radioactive fission products (cesium, iodine, etc.) started to mix with the water and steam. It was reported that a small amount of cesium and iodine was measured in the steam that was released into the atmosphere.
Since the reactor’s cooling capability was limited, and the water inventory in the reactor was decreasing, engineers decided to inject sea water (mixed with boric acid – a neutron absorber) to ensure the rods remain covered with water. Although the reactor had been shut down, boric acid is added as a conservative measure to ensure the reactor stays shut down. Boric acid is also capable of trapping some of the remaining iodine in the water so that it cannot escape, however this trapping is not the primary function of the boric acid.
The water used in the cooling system is purified, demineralized water. The reason to use pure water is to limit the corrosion potential of the coolant water during normal operation. Injecting seawater will require more cleanup after the event, but provided cooling at the time.
This process decreased the temperature of the fuel rods to a non-damaging level. Because the reactor had been shut down a long time ago, the decay heat had decreased to a significantly lower level, so the pressure in the plant stabilized, and venting was no longer required.
***UPDATE – 3/14 8:15 pm EST***
Units 1 and 3 are currently in a stable condition according to TEPCO press releases, but the extent of the fuel damage is unknown. That said, radiation levels at the Fukushima plant have fallen to 231 micro sieverts (23.1 millirem) as of 2:30 pm March 14th (local time).
***UPDATE – 3/14 10:55 pm EST***
The details about what happened at the Unit 2 reactor are still being determined. The post on what is happening at the Unit 2 reactor contains more up-to-date information. Radiation levels have increased, but to what level remains unknown.
So I take it you are hanging your hat on IF the can be imported, not ARE they imported so it better matches your predetermined choice of energy sources.
I'm not hanging my hat on anything. I merely put forth my opinion on the subject of energy and why I have that opinion. There's nothing nefarious in my opinion that energy independence is a worthy goal nor is there anything wrong with my opinion that energy independence will be a key part of our survival as a nation long-term. I"m being quite civil in saying that.
------------------ Bring back civility and decorum!
It's possible to understand someone's point of view without accepting it. It's possible to disagree with someone without being rude and nasty about it. Sure it's hard, but nothing worth doing is ever easy, is it?
Since LWR is apparently inherently safe, why not just stop worrying about these reactors? So what if their fuel melts into a puddle in the bottom of the reactor, it's not dangerous in any way just sitting there, it can't get out, it can't be hazardous outside the containment vessel. Why keep trying to cool it, etc? From what I've read here, adding water only makes things worse because of the void coefficient. Heck the water is the source of the hydrogen and steam explosions. What harm can come of just walking away?
------------------ Bring back civility and decorum!
It's possible to understand someone's point of view without accepting it. It's possible to disagree with someone without being rude and nasty about it. Sure it's hard, but nothing worth doing is ever easy, is it?
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11:43 AM
ryan.hess Member
Posts: 20784 From: Orlando, FL Registered: Dec 2002
There must be a reason why they're using desperate tactics to cool the cores even though the reactors are of an inherently safe design that's supposed to self-moderate in the absence of cooling. There's a dissonance there I'm not understanding.
I'd really like to see all the pertinent info rather than just the cherry-picked bits supplied by the proponents of nuclear power.
------------------ Bring back civility and decorum!
It's possible to understand someone's point of view without accepting it. It's possible to disagree with someone without being rude and nasty about it. Sure it's hard, but nothing worth doing is ever easy, is it?
Reliable scientific data?!? Blasphemy! I think the cores might have the potential to explode and maybe kill the all the black squirrels if the winds blow from the southnorth and the cloud travels 3000 miles without any dispersement... and its a tuesday... maybe...
The fringe sites are reporting "mass evacuations" of Tokyo, but the only thing that is supported by my sources is panic buying and some voluntarily relocations south.
Re-labeling of power plants in Japan Fukushima #1 = Fukushima Dai-ichi Fukushima #2 = Fukushima Daini 6.4 Quake just south of Tokyo. No worry of tidal damage.
I am noting posts related to what TEPCO is reporting. TEPCO has been the main source of public information for the Japanese government web posts regarding the Fukushima power plants.
Damn near everyone including Japanese news sources discount TEPCO provided information because of that companies history of lying, disinformation and coverups.
Watch NHK live feed: http://search.japantimes.co...in/nn20110316a2.html This source can be flaky but all press conferences have been posted here. Also, they are an "official" channel and have seemed to begin to lag the news to this channel.
[This message has been edited by Wudman (edited 03-15-2011).]
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02:04 PM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
Don't know anything about the source, but if this is true.... http://www.bellona.org/arti...2011/apparent_breach "The containment vessel at the embattled No 2 reactor at the Fukushima Daiichi nuclear power plant has apparently been breached, according to the Tokyo Electric Power Co (TEPCO), which runs the earthquake-stricken facility."
