Jdietz Posted March 17, 2011 Share Posted March 17, 2011 As far as I know, the power line has been run up to the plant, but not connected to the switchboard yet due to radiation levels at the site. I'll see if I can find a reference. Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 (edited) NHK: US to measure radioactivity in Japan The United States says it will conduct its own measurements of radioactivity in Japan in the wake of radiation leaks from an earthquake-damaged nuclear power plant in Fukushima Prefecture. US Ambassador John Roos told reporters in Tokyo on Wednesday that measuring equipment and 34 experts arrived in Japan the previous day. The equipment included instruments for measuring radiation levels on the ground and in the air and computer systems to process the data. Roos said the US is deploying all these capabilities because it's important to provide as much assistance to the Japanese as possible. He also said ensuring the safety of the US citizens in Japan is their highest concern, adding that it doesn't mean his government doesn't trust data provided by Japan. Roos reiterated that his government will provide continued support to Japan, adding that 7 experts from the US Nuclear Regulatory Commission arrived in the country on Wednesday. The US government has already sent 4 experts from the commission, the Energy Department and the Health and Human Services. Wednesday, March 16, 2011 20:19 +0900 (JST) http://www3.nhk.or.j...lish/16_44.html Edited March 17, 2011 by jfchandler Link to comment Share on other sites More sharing options...
brahmburgers Posted March 17, 2011 Share Posted March 17, 2011 (edited) If they pull this off, we're more or less out of the woods. The reactors themselves never really worried me much, as even a worst-case failure only means a very expensive site cleanup (contained melt-down). The open storage pools are a big deal though IMHO, once they get power and circulation back to them, it will be safe. Cleanup will be a long term operation though, I don't think anything at the Daiichi site will ever produce power again. I'm no expert, but I can't see how it will be safe any time soon. If there was a partial melt down (#1 and #3) as reported earlier, then it would seem the meltdown continues, at least for awhile. For a meltdown to be stopped, it would seem that all the components would have to be lined up to mechanical tolerances, perhaps fractions of mm's - in order to move components (in to water reservoir, for example) as needed. From all we've been hearing, much of the mechanical components at the reactors have been damaged. Oh, upon re-reading the above post, it references 'Daiichi' - so perhaps that's a lot different scenario than Fukushima. Also: there's still a better than even possibility that a strong aftershock (8 or more?) could strike, as that's been the pattern for pretty much all earthquakes off Japan. Sometimes the big aftershock doesn't hit for as long as a year later. It's even happened where an aftershock is mightier than the original earthquake. Edited March 17, 2011 by brahmburgers Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 (edited) Japan defense minister holding news conference: four helicopter water drops thus far..mentioning only Reactor 3. In afternoon, Tokyo police will use water cannon. With 11 vehicles. We believe it (helicopter drops) helped to cool down the fuel... However... not able to evaluate results/success as yet. Future air ops to be considered "as necessary" Edited March 17, 2011 by jfchandler Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 (edited) Edano news conference live broadcast: For relief supplies, please don't send perishable goods... Kan and President Obama talked on telephone 10:22 am...for half hour today. Obama expressed sympathy... offered U.S. support for mid and long term rehabilitation initiatives (re the reactors) Re water spraying, have completed morning part of air operations. There has been somewhat of a time lag in providing the pertinent information to U.S. authorities - regarding status of Reactor 4 water pools. Edano asked by Japanese reporters about difference between 20-30 Km evacuation/stay indoors orders for Japanese nationals vs. U.S. announcement excluding U.S. troops from 90 Km area around reactors... No indication from Edano that Japanese govt. plans to expand current 20 and 30 Km restrictions for Japanese. Edited March 17, 2011 by jfchandler Link to comment Share on other sites More sharing options...
webfact Posted March 17, 2011 Share Posted March 17, 2011 Japanese def. minister Kitazawa says 11 'special purpose vehicles' to spray water on reactors - BBC http://bbc.in/gsjWCQ /RT @BreakingNews: Link to comment Share on other sites More sharing options...
Lopburi99 Posted March 17, 2011 Share Posted March 17, 2011 (edited) Big lag in CNN's reporting. They're way behind. They are overly negative now. They need to access this thread guys. Basically forget about being informed by any US based news station. They seem to exist solely to push their respective political stance. Right. And now CNN has started bad-mouthing the Japanese government. Just watch them piss off Kan the way they pissed off Abhisit last year' date=' courtesy Dan Rivers and Sara Snider [img']http://static.thaivisa.com/forum/public/style_emoticons/default/ph34r.gif[/img] (CNN Breaking news: Fire trucks on the way) Edited March 17, 2011 by Lopburi99 Link to comment Share on other sites More sharing options...
Jdietz Posted March 17, 2011 Share Posted March 17, 2011 I'm no expert, but I can't see how it will be safe any time soon. If there was a partial melt down (#1 and #3) as reported earlier, then it would seem the meltdown continues, at least for awhile. For a meltdown to be stopped, it would seem that all the components would have to be lined up to mechanical tolerances, perhaps fractions of mm's - in order to move components (in to water reservoir, for example) as needed. From all we've been hearing, much of the mechanical components at the reactors have been damaged. I've posted this already but let me repeat: A full meltdown in these kind of reactors means that the radioactive material in the rods melt, to form a puddle at the bottom of the steel containment vessel. This will further dissipate the heat of the reaction until it becomes a brittle substance you can basically break away from the bottom and remove piece by piece. Expensive cleanup, yes. Dangerous Nuclear Explosion, not really. I'm really more worried about the storage pools. The reactors never bothered me too much. Link to comment Share on other sites More sharing options...
atsiii Posted March 17, 2011 Share Posted March 17, 2011 (edited) Edano (sp?) on NHK TV now acknowledging they have been slow in getting information to the Americans, but are upset that the US told its citizens to move 80km away from the plant. Also denying that US Military Officers are being turned away by Japanese officials at a 80km distance from the plant (I had not heard this). Just what we need right now--trying to save face instead of lives. Edited March 17, 2011 by atsiii Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 Scientists Project Path of Radiation Plume A United Nations forecast of the possible movement of the radioactive plume coming from crippled Japanese reactors shows it churning across the Pacific, and touching the Aleutian Islands on Thursday before hitting Southern California late Friday. http://www.nytimes.c...plume.html?_r=1 Thanks for posting the link on this... Note the article also includes the following: Health and nuclear experts emphasize that radiation in the plume will be diluted as it travels and, at worst, would have extremely minor health consequences in the United States, even if hints of it are ultimately detectable. The forecast, calculated Tuesday, is based on patterns of Pacific winds at that time and the predicted path is likely to change as weather patterns shift. The forecast assumes that radioactivity in Japan is released continuously and forms a rising plume. It ends with the plume heading into Southern California and the American Southwest, including Nevada, Utah and Arizona. The plume would have continued eastward if the United Nations scientists had run the projection forward. Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 NHK reporting police say death toll from quake and tsunamis now exceeding 5000. Link to comment Share on other sites More sharing options...
manarak Posted March 17, 2011 Share Posted March 17, 2011 Am I the only one feeling some signs of optimism for the first time in days? I don't want to sound too pessimistic, but if I am not mistaken, the pools hold approx. 3400 cubic meters each, and one ton of water is approx. one cubic meter. Each heli brings 7.5 tons and each truck 4 tons. Do the math, knowing that several pools make problems, and knowing that the trucks and helis are unable to deliver all their water directly into the pools. They have to aim and hope that most of it goes into the pool. 50% is probably an optimistic estimate. And about the reactors themselves, a total meltdown is likely to breach through the containment vessels. So far, what I learned about early NPP designs is rather unimpressive if considering the redundancy (or lack thereof) of critical systems. In fighter airplanes, many critical circuits are not duplicated to prevent failure, they are triplicated! And an airplane crash only kills the pilot(s) plus maybe some people on the ground, not millions lives at stake as in an NPP. I am a bit disappointed and alarmed that there are not more emergency systems at the technicians' disposal. One would think that because of the huge damage potential incase of accident, they would design he plants with 5 or 6 different ways to cool the rods and build the pools in a way that they cannot leak and would resist explosions. But apparently no. Only having some diesels, batteries and the normal grid power to run the pumps also seems on the light side. I am not impressed by the system engineering. I have questions for the specialists: - the rods in the pools: are their atom cores still splitting or has the chain reaction been stopped and it is only "residual energy" that causes the heat, and will that energy eventually dissipate by itself, even without cooling?? Are the rods in the pools dangerous because they could resume chain reaction or just because their heat could cause fires whose smoke would spread radioactive material into the atmosphere? - the reactors: they have all been shut down before the tsunami, and this means, as far as I learned, that the control rods have been raised into the core, stopping the fission chain reaction. So do we have here the same situation as in the pools, just with hotter rods? If a meltdown occurs, what are the chances or temperatures in excess of 2000 degrees occuring that would destroy the containment vessel? - About the new power line: this would hopefully restore power to pumps, but the cooling pumps would not be of great use if there is no water to cool in the reactor, right? Do these plants even have pumps to pump seawater into the reactor core? I suppose they would have to send some people out to do some plumbing outside, very near to where the radiation leaks from? Will the workers there "take one for the team"? I wonder how much nuclear power managers will commit sepuku in the next weeks. Link to comment Share on other sites More sharing options...
StreetCowboy Posted March 17, 2011 Share Posted March 17, 2011 .... question: if a fuel rod is sitting dry on its own, will it heat up and emit radioactivity? How much less problematical is a spent U rod compared to a relatively new rod? .... There was mention yesterday that #1 had a partial meltdown. If there's no coolant going in there, then it would seem the meltdown in #1 is continuing (and worsening?), as there would seem to be nothing to slow it down. 1) Yes, the rod will heat up on its own; whether it will reach such a temperature that the metal cladding melts or spontaneously combusts, I don't know; that depends on the effectiveness of convective air-cooling over it, which is entirely passive. The heat comes from the decay of radio-active material from the fission products that remain in the fuel - see next para. 2) A new fuel rod - particularly one that is not Mixed Oxide (MOX) i.e. contains only Uranium and does not contain any plutonium, is relatively benign and would not pose an emergency situation. However, after the rod has been in the reactor, some of the U235 (and some of the U238 -> Pu239) will have split into two smaller atoms - which are in turn unstable, and decay gradually until eventually they reach a stable state, giving off radiation and heat all the while. Not only are these smaller atoms radioactive, because they are a different chemical composition (and therefore different density, different checmical bonding) the irradiated fuel pin within the cladding is less structurally sound - hence why we need the metal cladding to retain the fission products, some of which are gases. Someone mentioned earlier that at shut-down, the decay heat from fission products inside the reactor is as much as 14% (seems high but possible) of the normal reactor power output, though this reduces quickly as the most unstable isotopes decay to longer-lifetime isotopes; by the time the fuel is out of the reactor and held in the fuel ponds for a while, its heat (and radiation) output is much less. The older fuel rods will give out much less heat and radiation than those fresh from the reactor. So because the decay heat dies off, a meltdown will eventually stabilise of its own accord - it would require more complex modelling than I am capable of to tell you what would happen in the mean time... cleverer people than me have probably spent a lot of time doing sums to look at what happens in such cases... SC Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 (edited) Here's what the Edano reference about delayed info being given to the Americans is about....being the NRC's assessment to Congress on Wednesday about radiation levels... U.S. basically saying No. 4 reactor pool empty or close to that. Japan denying that. The New York Times March 16, 2011 U.S. Calls Radiation 'Extremely High,' Sees Japan Nuclear Crisis Worsening WASHINGTON — The chairman of the United States Nuclear Regulatory Commission gave a far bleaker appraisal on Wednesday of the threat posed by Japan's nuclear crisis than the Japanese government had offered. He said American officials believed that the damage to at least one crippled reactor was much more serious than Tokyo had acknowledged, and he advised Americans to stay much farther away from the plant than the perimeter established by Japanese authorities. The announcement opened a new and ominous chapter in the five-day-long effort by Japanese engineers to bring the six side-by-side reactors under control after their cooling systems were knocked out by an earthquake and a tsunami last Friday. It also suggested a serious split between Washington and its closest Asian ally at an especially delicate moment. The Congressional testimony by Gregory Jaczko, the chairman of the commission, was the first time the Obama administration had given its own assessment of the condition of the plant, apparently mixing information it had received from Japan with data it had collected independently. MORE: http://www.nytimes.c...tml?ref=science Edited March 17, 2011 by jfchandler Link to comment Share on other sites More sharing options...
atsiii Posted March 17, 2011 Share Posted March 17, 2011 NHK weather forecasts: winds are now SE out to sea, but will turn to the south towards Tokyo on Saturday. Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 - About the new power line: this would hopefully restore power to pumps, but the cooling pumps would not be of great use if there is no water to cool in the reactor, right? Do these plants even have pumps to pump seawater into the reactor core? I suppose they would have to send some people out to do some plumbing outside, very near to where the radiation leaks from? Will the workers there "take one for the team"? The NISA guy this morning was saying they hope to set up a temporary cooling system using a new power line, repaired/cleaned up pumps and pulling sea water into the system to use inside the reactors... I'd be surprised if that's something they can get up and running quickly -- even leaving aside the issue of radiation levels potentially limiting the work. Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 I'm not sure I caught this right...but I think NHK was just reporting about TEPCO data on radiation levels before and after the airdrops...not much difference... 3.78 millisieverts per hour before 3.75 millisieverts per hour after not clear on the exact timing or location of those readings... Link to comment Share on other sites More sharing options...
Jdietz Posted March 17, 2011 Share Posted March 17, 2011 Yeah you got it NBK World: No significant change in radiation levels after water dump. Spent fuel pond almost empty Dumping water mostly missed the pool Pool size about 2,000 tons. 1/3rd needs to be filled to submerge the fuel rods. Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 TEPCO on NHK saying they started water drops on Reactor 3 today because helicopter view yesterday of Reactor 4 showed there is still water in the #4 spent fuel pool. Not saying how much. Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 (edited) More from the NYT: This surely didn't make the Japanese happy.... "We would recommend an evacuation to a much larger radius than has currently been provided by Japan," Mr. Jaczko said. That assessment seems bound to embarrass, if not anger, Japanese officials, suggesting they have miscalculated the danger or deliberately played down the risks. Nor would this: American officials who have been dealing with their Japanese counterparts report that the country's political and bureaucratic leadership has appeared frozen in place, unwilling to communicate clearly about the scope of the problem and, in some cases, unwilling to accept outside assistance. Two American officials said they believed that the Japanese government itself was not getting a clear picture from the Tokyo Electric Power Company. No wonder Kan and Obama spoke on the phone this morning... Edited March 17, 2011 by jfchandler Link to comment Share on other sites More sharing options...
atsiii Posted March 17, 2011 Share Posted March 17, 2011 Am I the only one feeling some signs of optimism for the first time in days? I don't want to sound too pessimistic, but if I am not mistaken, the pools hold approx. 3400 cubic meters each, and one ton of water is approx. one cubic meter. Each heli brings 7.5 tons and each truck 4 tons. Do the math, knowing that several pools make problems, and knowing that the trucks and helis are unable to deliver all their water directly into the pools. They have to aim and hope that most of it goes into the pool. 50% is probably an optimistic estimate. And about the reactors themselves, a total meltdown is likely to breach through the containment vessels. So far, what I learned about early NPP designs is rather unimpressive if considering the redundancy (or lack thereof) of critical systems. In fighter airplanes, many critical circuits are not duplicated to prevent failure, they are triplicated! And an airplane crash only kills the pilot(s) plus maybe some people on the ground, not millions lives at stake as in an NPP. I am a bit disappointed and alarmed that there are not more emergency systems at the technicians' disposal. One would think that because of the huge damage potential incase of accident, they would design he plants with 5 or 6 different ways to cool the rods and build the pools in a way that they cannot leak and would resist explosions. But apparently no. Only having some diesels, batteries and the normal grid power to run the pumps also seems on the light side. I am not impressed by the system engineering. I have questions for the specialists: - the rods in the pools: are their atom cores still splitting or has the chain reaction been stopped and it is only "residual energy" that causes the heat, and will that energy eventually dissipate by itself, even without cooling?? Are the rods in the pools dangerous because they could resume chain reaction or just because their heat could cause fires whose smoke would spread radioactive material into the atmosphere? - the reactors: they have all been shut down before the tsunami, and this means, as far as I learned, that the control rods have been raised into the core, stopping the fission chain reaction. So do we have here the same situation as in the pools, just with hotter rods? If a meltdown occurs, what are the chances or temperatures in excess of 2000 degrees occuring that would destroy the containment vessel? - About the new power line: this would hopefully restore power to pumps, but the cooling pumps would not be of great use if there is no water to cool in the reactor, right? Do these plants even have pumps to pump seawater into the reactor core? I suppose they would have to send some people out to do some plumbing outside, very near to where the radiation leaks from? Will the workers there "take one for the team"? I wonder how much nuclear power managers will commit sepuku in the next weeks. I'm not an expert either, but I am a pilot. Even the DC-10 has triple backed up hydraulics systems, yet a DC=10 departed Denver, lost an engine, and it took out all three systems. Statistically impossible... tell the pilot, who amazingly crash landed the A/C in South Dakota saving most of the passengers. ... talk about on the brink with no backups, ask yourself what would happen if a large after shock hit today, causing another tsunami that swamped the site? That's what happens in cockpits... it's rarely the first event/malfunction that proves fatal, it's the the progression or sequence of events/errors that keeps building up. When the reactors are shut down, I don't think the fuel rods are withdrawn, rather I think control rods are inserted. The rods in the cooling pools must be cooled and submerged in water. They cannot cool themselves and if totally exposed, will ultimately ignite, burn and decay. #4 was in maintenance, so all of it's relatively new (and hot) fuel rods were removed from the core and placed into the #4 cooling pool. Thus, that pool contains not only spent fuel rods but also the entire core's rods. Keep your fingers crossed... Link to comment Share on other sites More sharing options...
animatic Posted March 17, 2011 Share Posted March 17, 2011 (edited) Here is some interesting reading about 'pool fires' http://brc.gov/e-mai...teConfRpt09.pdf The accident sequences that could result in water loss from the SFP, including beyond design basis earthquakes, various types of seal failures and dropped shipping casks, and the Zircaloy cladding fire issues have been studied by the NRC staff. The results of these studies are provided in NUREG-1353, "Regulatory Analysis for the Resolution of Generic Issue 82, Beyond Design Basis Accidents in Spent-Fuel Pools". Although these studies conclude that most of the spent-fuel pool risk is derived from beyond design basis earthquakes, this risk is not greater than the risk from core damage accidents due to these beyond design basis earthquakes. Therefore, reducing the risk from spent-fuel pools due to events beyond the safe shutdown earthquake would still leave a comparable risk due to core damage accidents. The risk due to beyond design basis accidents in spent-fuel pools, while not negligible, is sufficiently low that the added cost involved with further risk reduction is not warranted. It doesn't seem to address the logical idea that if the pool is damaged, and the core is damaged by earthquakes or other cause, that they could be damaged together. Not just one or the other, but both in tandem, and the risk of BOTH together is much greater and potentially exponentially harder to deal with. Expanding on this if the rod storage pools are above the reactor vessel, and their rods melt and pool nuclear materials, and cause damage to the pool bottom, does this not allow nuclear matter to drop down next to the containment vessel? Meaning there is supper hot material on BOTH sides of the containment vessel in and out. Are the containment vessels and containment buildings design to be superheated from BOTH sides? Edited March 17, 2011 by animatic Link to comment Share on other sites More sharing options...
Jdietz Posted March 17, 2011 Share Posted March 17, 2011 Gomenasai (ごめんなさい) (I'm sorry) can almost be translated straight as Mai pen rai (ไม่เป็นไร)... not that much cultural difference in that regard. Link to comment Share on other sites More sharing options...
webfact Posted March 17, 2011 Share Posted March 17, 2011 FLASH: Japan nuclear operator: As of Wednesday, spent-fuel pool at no.4 reactor still had water in it /via@Reuters Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 (edited) I feel so much better now... Nuclear Agency Tells a Concerned Congress That U.S. Industry Remains Safe Published: March 16, 2011 WASHINGTON — Facing questions about the implications of Japan's nuclear catastrophe for power plants in the United States, the Nuclear Regulatory Commission's top official said Wednesday at two Congressional hearings that his agency would take a methodical look at Japan and incorporate lessons from the disaster. The pledge from the official, Gregory Jaczko, the commission's chairman, drew praise and criticism that was often consonant with a lawmaker's political position on nuclear power and other forms of energy. "U.S. nuclear facilities remain safe," Mr. Jaczko told two House Energy and Commerce subcommittees, which had originally planned to consider his agency's budget for the coming fiscal year at the hearing. "We will continue to work to maintain that level of protection." MORE: http://www.nytimes.c...c.html?ref=asia Edited March 17, 2011 by jfchandler Link to comment Share on other sites More sharing options...
JulianLS Posted March 17, 2011 Share Posted March 17, 2011 Am I the only one feeling some signs of optimism for the first time in days? I don't want to sound too pessimistic, but if I am not mistaken, the pools hold approx. 3400 cubic meters each, and one ton of water is approx. one cubic meter. Each heli brings 7.5 tons and each truck 4 tons. Do the math, knowing that several pools make problems, and knowing that the trucks and helis are unable to deliver all their water directly into the pools. They have to aim and hope that most of it goes into the pool. 50% is probably an optimistic estimate. And about the reactors themselves, a total meltdown is likely to breach through the containment vessels. So far, what I learned about early NPP designs is rather unimpressive if considering the redundancy (or lack thereof) of critical systems. In fighter airplanes, many critical circuits are not duplicated to prevent failure, they are triplicated! And an airplane crash only kills the pilot(s) plus maybe some people on the ground, not millions lives at stake as in an NPP. I am a bit disappointed and alarmed that there are not more emergency systems at the technicians' disposal. One would think that because of the huge damage potential incase of accident, they would design he plants with 5 or 6 different ways to cool the rods and build the pools in a way that they cannot leak and would resist explosions. But apparently no. Only having some diesels, batteries and the normal grid power to run the pumps also seems on the light side. I am not impressed by the system engineering. I have questions for the specialists: - the rods in the pools: are their atom cores still splitting or has the chain reaction been stopped and it is only "residual energy" that causes the heat, and will that energy eventually dissipate by itself, even without cooling?? Are the rods in the pools dangerous because they could resume chain reaction or just because their heat could cause fires whose smoke would spread radioactive material into the atmosphere? - the reactors: they have all been shut down before the tsunami, and this means, as far as I learned, that the control rods have been raised into the core, stopping the fission chain reaction. So do we have here the same situation as in the pools, just with hotter rods? If a meltdown occurs, what are the chances or temperatures in excess of 2000 degrees occuring that would destroy the containment vessel? - About the new power line: this would hopefully restore power to pumps, but the cooling pumps would not be of great use if there is no water to cool in the reactor, right? Do these plants even have pumps to pump seawater into the reactor core? I suppose they would have to send some people out to do some plumbing outside, very near to where the radiation leaks from? Will the workers there "take one for the team"? I wonder how much nuclear power managers will commit sepuku in the next weeks. The rods in the storage pools are still decaying, which produces heat and radiation. The likelihood of a chain reaction is very low, because the rods are spaced, and because their is no moderator present in the storage pools (a moderator slows down neutrons, making them more suitable to cause a chain reaction). Rather, neutron absorbers (boron) is added to the pool to quench any chain reaction. The biggest concern is that the pools run dry. In this situation, the rods can heat up to high temperatures, and either produce hydrogen (from residual water) or catch fire (uranium can burn). In these scenarios the spread of radioactive material is much worse. The danger is primarily the rods catching fire. A nuclear chain reaction is possible in theory but very unlikely in practice. Even Chernobyl was a thermal explosion not a nuclear one. The situation in the shut down reactors is in a way like the storage pools, with heat coming from natural decay not a chain reaction. But the rods are closer together and a moderator (graphite) is present, as well as neutron absorbers (ie. the control rods). In theory, temperatures above 2000 degrees could be achieved in a meltdown. There is an unlimited supply of water at Fukushima Daiichi, it's right by the sea. Once the power is available, the biggest problem is the availability of suitably large pumps, and the ability to set them up given the high levels of radiation in and around the reactors. Existing pumps have been damaged by salt water from the tsunami. Let's hope today's actions can get reactor #3 and the storage pools under control. Link to comment Share on other sites More sharing options...
jfchandler Posted March 17, 2011 Share Posted March 17, 2011 Here's what the Edano reference about delayed info being given to the Americans is about....being the NRC's assessment to Congress on Wednesday about radiation levels... U.S. basically saying No. 4 reactor pool empty or close to that. Japan denying that. Saying No. 3 pool is more critical. The New York Times March 16, 2011 U.S. Calls Radiation 'Extremely High,' Sees Japan Nuclear Crisis Worsening WASHINGTON — The chairman of the United States Nuclear Regulatory Commission gave a far bleaker appraisal on Wednesday of the threat posed by Japan's nuclear crisis than the Japanese government had offered. He said American officials believed that the damage to at least one crippled reactor was much more serious than Tokyo had acknowledged, and he advised Americans to stay much farther away from the plant than the perimeter established by Japanese authorities. The announcement opened a new and ominous chapter in the five-day-long effort by Japanese engineers to bring the six side-by-side reactors under control after their cooling systems were knocked out by an earthquake and a tsunami last Friday. It also suggested a serious split between Washington and its closest Asian ally at an especially delicate moment. The Congressional testimony by Gregory Jaczko, the chairman of the commission, was the first time the Obama administration had given its own assessment of the condition of the plant, apparently mixing information it had received from Japan with data it had collected independently. MORE: http://www.nytimes.c...tml?ref=science Link to comment Share on other sites More sharing options...
atsiii Posted March 17, 2011 Share Posted March 17, 2011 NHK reporting police say death toll from quake and tsunamis now exceeding 5000. They just added that > 14,600 missing. Link to comment Share on other sites More sharing options...
webfact Posted March 17, 2011 Share Posted March 17, 2011 Just in via the White House - Readout of the President's Call with Japanese Prime Minister Kan: http://bit.ly/gWIpSa /RT @mpoppel: Link to comment Share on other sites More sharing options...
webfact Posted March 17, 2011 Share Posted March 17, 2011 Quake-tsunami death toll as of 10 a.m. is 5,176, with 8,606 people missing, according to the police. /RT @DailyYomiuri: Link to comment Share on other sites More sharing options...
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