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Talk about coincidence tho -- Just last week I reviewed the youtube library of Chernobyl documentaries. Maybe I had a small inkling of an impending nuclear catastrophe.
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2001: A senior nuclear industry executive has told the New York Times that Japanese nuclear power industry managers are "basically in a full-scale panic". The executive is not involved in managing the response to the reactors' difficulties but has many contacts in Japan. "They're in total disarray, they don't know what to do," the executive added.
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2022: A Russian diplomatic source has told the Interfax news agency that Moscow is "awaiting trustworthy information regarding the situation at Japanese nuclear power plants" from the authorities in Tokyo. The source said Russian officials had not ruled out that the Japanese were playing down the possible threat for fear of causing panic among members of the public. Moscow planned to send seismologists to Japan to assess the situation on the ground so it could be "a thousand times more sure that everything is safe", the source added.
http://en.wikipedia.org/wiki/Nuclear_meltdown#Light_water_reactors
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2. Pre-damage heatup. "In the absence of a two-phase mixture going through the core or of water addition to the core to compensate water boiloff, the fuel rods in a steam environment will heatup at a rate between 0.3 K/s (.5 F/s) and 1 K/s (2.13 F/s) (3)."[7]
3. Fuel ballooning and bursting. "In less than half an hour, the peak core temperature would reach 1100 K (1520 F). At this temperature, the zircaloy cladding of the fuel rods may balloon and burst. This is the first stage of core damage. Cladding ballooning may block a substantial portion of the flow area of the core and restrict the flow of coolant. However complete blockage of the core is unlikely because not all fuel rods balloon at the same axial location. In this case, sufficient water addition can cool the core and stop core damage progression."[7]
4. Rapid oxidation. "The next stage of core damage, beginning at approximately 1500 K (2240 F), is the rapid oxidation of the Zircaloy by steam. In the oxidation process, hydrogen is produced and a large amount of heat is released. Above 1500 K, the power from oxidation exceeds that from decay heat (4,5) unless the oxidation rate is limited by the supply of either zircaloy or steam."[7]
5. Debris bed formation. "When the temperature in the core reaches about 1700 K (2600 F), molten control materials [1,6] will flow to and solidify in the space between the lower parts of the fuel rods where the temperature is comparatively low. Above 1700 K (2600 F), the core temperature may escalate in a few minutes to the melting point of zircaloy (2150 K, 3410 F)) due to increased oxidation rate. When the oxidized cladding breaks, the molten zircaloy, along with dissolved UO2 [1,7] would flow downward and freeze in the cooler, lower region of the core. Together with solidified control materials from earlier down-flows, the relocated zircaloy and UO2 would form the lower crust of a developing cohesive debris bed."[7]
6. (Corium) Relocation to the lower plenum. "In scenarios of small-break LOCAs, there is generally a pool of water in the lower plenum of the vessel at the time of core relocation. Release of molten core materials into water always generates large amounts of steam. If the molten stream of core materials breaks up rapidly in water, there is also a possibility of a steam explosion. During relocation, any unoxidized zirconium in the molten material may also be oxidized by steam, and in the process hydrogen is produced. Recriticality also may be a concern if the control materials are left behind in the core and the relocated material breaks up in unborated water in the lower plenum."[7]
At the point at which the corium relocates to the lower plenum, Haskin, et al relate that the possibility exists for an incident called a fuel-coolant interaction (FCI) to substantially stress or breach the primary pressure boundary when the corium relocates to the lower plenum of the reactor pressure vessel ("RPV").[9] This is because the lower plenum of the RPV may have a substantial quantity of water - the reactor coolant - in it, and, assuming the primary system has not been depressurized, the water will likely be in the liquid phase, and consequently dense, and at a vastly lower temperature than the corium. Since corium is a liquid metal-ceramic eutectic at temperatures of 2,200 to 3,200 K (3,500 to 5,300 °F), its fall into liquid water at 550 to 600 K (530 to 620 °F) may cause an extremely rapid evolution of steam that could cause a sudden extreme overpressure and consequent gross structural failure of the primary system or RPV.[9] Though most modern studies hold that it is physically infeasible, or at least extraordinarily unlikely, Haskin, et al state that that there exists a remote possibility of an extremely violent FCI leading to something referred to as an alpha-mode failure, or the gross failure of the RPV itself, and subsequent ejection of the upper plenum of the RPV as a missile against the inside of the containment, which would likely lead to the failure of the containment and release of the fission products of the core to the outside environment without any substantial decay having taken place.[10]
However, it is likely, as in the Three Mile Island accident, that any FCI that occurs will not substantially breach the primary pressure boundary, or lead to the gross structural failure of the primary system or RPV, and the corium will reach the lower plenum with the lower plenum remaining intact.
Following corium relocation to the lower plenum, the potential exists for corium to breach the primary pressure boundary (in light water reactors, this is the reactor pressure vessel). What happens when the corium reaches the bottom of the reactor pressure vessel in a Western light water reactor is the subject of actual experience and considerable speculation, and depends on temperatures, the age of the fuel, the amount of activity the fuel has been exposed to, as well as the physical composition of the RPV, the dimensions of the RPV, the pressure of the primary coolant system (whether or not pressurized) and numerous other considerations. It is not likely for the corium to remain critical in the bottom of the RPV unless - first - the corium is quenched by a large excess of coolant water and turned back into solid phase, allowing the interposition of a water moderator and the formation of a critical geometry - second - after the quench of the corium, there remains sufficient unborated water in the lower plenum to moderate the reaction and support criticality - third - the corium remains unadulterated with a neutron-absorptive alloy or substance from the melt of the control rods, such as boron carbide or cadmium.
If the worst case is assumed, there remains at least some tens of minutes to a number of hours from corium relocation to the lower plenum to RPV breach in a maximally contingent Western LWR limiting fault with complete loss of the ECCS. Even partial ECCS activation can delay this significantly, and provide time for the remainder of the ECCS to be brought back online; it is highly unlikely that the staff of a Western LWR will be completely unable to restore at least part of the ECCS prior to the RPV being breached. ECCS activation may not be as useful as might be thought, however, if the corium has intense decay heat and is in a non-coolable geometry (for instance, the core is at end of cycle and the corium has formed a deep pool); in these circumstances, the ECCS may not remove sufficient decay heat and breach may be inevitable. Further, quench of the corium induced by ECCS activation may result in hydrogen production and evolution of large volumes of steam.
Rapid RPV breach is not inevitable in the event of corium relocation to the lower plenum, and corium relocation may be recoverable from without RPV breach. The Three Mile Island accident proved this - in that accident, solid corium quenched by coolant left in the lower plenum of the RPV formed a layer of shielding on the lower plenum of the RPV, limiting most of the damage to the reactor itself, and providing time for the ECCS to be returned to functioning. The American Nuclear Society has said "despite melting of about one-third of the fuel, the reactor vessel itself maintained its integrity and contained the damaged fuel".[11] However the Three Mile Island example, though illustrative of the comprehensive approach of defense in depth against all contingencies, also illustrates the difficulty in predicting such behavior: the reactor vessel was not built for, and not expected to remain intact with, the temperatures it experienced when the core melted, but possibly because some of the melted material collected at the bottom of the vessel and cooled early on in the accident, it created a resistant shell against further pressure and heat. Such a possibility was not predicted by the engineers who designed the reactor and would not necessarily occur under duplicate conditions, but was largely seen as instrumental in the preservation of the reactor vessel's integrity. (However, the reactor vessel was inside a containment building, as in all non-Soviet nuclear plants, so a failure of the reactor vessel would not automatically mean that radioactive material would be released into the environment.)
If the primary pressure boundary is not substantially breached by corium, the accident is described as a "partial meltdown", and the chain of events stops when satisfactory cooling of the remaining fuel, corium, and the RPV is restored. A partial meltdown is an INES Level 4 or 5 accident, depending on the degree of damage. If the primary pressure boundary is substantially breached by corium, the accident is described as a "full meltdown", which is an INES Level 5 accident and can escalate to INES Level 6 if events progress in a highly prejudicial fashion. The longer the reactor operators are able to retain the fission products within the containment, the less radioactive material will be released. The most highly radioactive isotopes in a fission product mixture are short lived. For example if all the iodine in a core was released one week after shutdown, then the thyroid dose suffered by the population would be lower than if the radioiodine had escaped the plant one hour after the reactor was stopped.
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2129: Tepco said water levels inside the containment vessel were not immediately rising to the desired level, possibly because of a leak. Nevertheless, an official told a news conference: "We do not feel that a critical event is imminent."
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2126: Engineers were having difficulty injecting seawater into the reactor because its vents - necessary to release pressure in the containment vessel by allowing radioactive steam to escape - had stopped working properly, the New York Times reports. However, by Tuesday morning they had succeeded in opening a malfunctioning valve, reducing pressure in the container vessel. They then resumed flooding the reactor with water.
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2124: Work resumed early on Tuesday morning to pump sea water into reactor 2 at Fukushima Daiichi to prevent its fuel rods inside from overheating. As of 0300 local time on Tuesday, pressure inside the reactor container had dropped and it was believed seawater had been pumped in succesfully, Tepco said, according to the Kyodo news agency. However, Tepco admitted that it had not yet been able to confirm that water levels inside the reactor had risen. The fuel rods were fully exposed at 2300 local time on Monday.
professorpan wrote:For what it's worth, an old friend who flew Navy jets and knows the Japanese naval bases well wrote to me and said that as soon as the US ships started pulling away, he knew the situation was much more fucked than anyone was letting on. I think it's safe to assume that at least one meltdown has occurred—whether or not it will breach the containment vessel is unknown, but as the containment vessels in question have been alleged to have cracks I think it's quite possible (or, in nuke authority speak, "We don't feel that it is likely at this time").
2153: Lt Anthony Falvo of the US Navy tells the BBC that concerns about radiation from Japan's stricken nuclear power plants will not curtail the efforts of the 15,000 American sailors sent to the region to assist the rescue effort. "What we're trying to do is make it safe for our ships to move in a little bit closer, so that we can eventually assist the government of Japan in doing what they need to do," he says. "As part of that, what we're hoping is that the USS Ronald Reagan will serve as an afloat platform for re-fuelling helicopters from the Japan Defence Force, the Japanese coastguard, fire and police, and other civilian authorities involved in the rescue and recovery efforts ashore. We are absolutely committed to this mission and we look to see it through to the end."
The 7th Fleet said Monday morning it was moving its ships clear of the reactor to avoid any threat to their mission: helping the people of Japan.
7th Fleet moves ships, aircraft away from stricken Fukushima plant
By Jon Rabiroff | Stars and Stripes | Published: March 14, 2011
SEOUL -- The U.S. 7th Fleet has moved its ships and aircraft away from the Fukushima Dai-Ichi nuclear power plant in Japan after low levels of contamination were detected in the air and found on the crews of three helicopters returning from disaster relief missions near Sendai.
The contamination found on the 17 crewmembers was easily removed by washing with soap and water, and the ship and aircraft move is only temporary, according to a 7th Fleet release.
Later, a message from Capt. Thom Burke appeared on the Reagan’s Facebook page, confirming that the radiation levels detected were very low.
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“To put this into perspective, the maximum radiation dose received was equal to the amount of natural background radiation one would receive in one month from sources such as rocks, soil and the sun,” the message said. “I have not seen any levels of radiation or contamination that would cause me to have any significant concerns at all.”
The USS Ronald Reagan Carrier Strike Group was en route to South Korea to participate in a joint South Korean-U.S. military exercise this week, when it was diverted to Japan in the wake of Friday’s earthquake and tsunami.
As the search for survivors and victims of the disaster continues, officials are primarily concerned with the fate of two Fukushima nuclear reactors that are overheating.
The Reagan strike group arrived Sunday to provide support for operations in the Miyagi and Fukushima prefectures, two of the hardest-hit areas of Japan. It was operating in waters about 100 miles northeast of the plant when precautionary tests done on crews returning to the Ronald Reagan revealed contamination that was blamed on a radioactive plume released from the nuclear plant.
After the crewmen washed off, no further contamination was detected, officials said.
“As a precautionary measure,” the release said, the USS Ronald Reagan and other 7th Fleet ships in the area were moved out of the downwind direction of the plant “to assess the situation and determine what appropriate mitigating actions are necessary.”
Tokyo Electric to Build US Nuclear Plants: The No BS Info on Japan's Disastrous Nuclear Operators
Monday 14 March 2011
by: Greg Palast, t r u t h o u t | News Analysis
Texas nuclear plants planned by Tokyo Electric. (Image: NINA)
I need to speak to you, not as a reporter, but in my former capacity as lead investigator in several government nuclear plant fraud and racketeering investigations.
I don't know the law in Japan, so I can't tell you if Tokyo Electric Power Co (TEPCO) can plead insanity to the homicides about to happen.
But what will Obama plead? The administration, just months ago, asked Congress to provide a $4 billion loan guarantee for two new nuclear reactors to be built and operated on the Gulf Coast of Texas - by TEPCO and local partners. As if the Gulf hasn't suffered enough. Here are the facts about TEPCO and the industry you haven't heard on CNN:
The failure of emergency systems at Japan's nuclear plants comes as no surprise to those of us who have worked in the field.
Nuclear plants the world over must be certified for what is called "SQ" or "Seismic Qualification." That is, the owners swear that all components are designed for the maximum conceivable shaking event, be it from an earthquake or an exploding Christmas card from al-Qaeda.
The most inexpensive way to meet your SQ is to lie. The industry does it all the time. The government team I worked with caught them once, in 1988, at the Shoreham plant in New York. Correcting the SQ problem at Shoreham would have cost a cool billion, so engineers were told to change the tests from "failed" to "passed."
The company that put in the false safety report? Stone & Webster, now the nuclear unit of Shaw Construction, which will work with TEPCO to build the Texas plant. Lord help us.
There's more.
Last night, I heard CNN reporters repeat the official line that the tsunami disabled the pumps needed to cool the reactors, implying that water unexpectedly got into the diesel generators that run the pumps.
These safety backup systems are the "EDGs" in nuke-speak: Emergency Diesel Generators. That they didn't work in an emergency is like a fire department telling us they couldn't save a building because "it was on fire."
What dim bulbs designed this system? One of the reactors dancing with death at Fukushima Station 1 was built by Toshiba. Toshiba was also an architect of the emergency diesel system.
Now be afraid. Obama's $4 billion bailout in the making is called the South Texas Project. It's been sold as a red-white-and-blue way to make power domestically with a reactor from Westinghouse, a great American brand. However, the reactor will be made substantially in Japan by the company that bought the US brand name, Westinghouse - Toshiba.
I once had a Toshiba computer. I only had to send it in once for warranty work. However, it's kind of hard to mail back a reactor with the warranty slip inside the box if the fuel rods are melted and sinking halfway to the earth's core.
TEPCO and Toshiba don't know what my son learned in eighth grade science class: tsunamis follow Pacific Rim earthquakes. So, these companies are real stupid, eh? Maybe. More likely is that the diesels and related systems wouldn't have worked on a fine, dry afternoon.
Back in the day, when we checked the emergency backup diesels in America, a mind-blowing number flunked. At the New York nuclear plant, for example, the builders swore under oath that their three diesel engines were ready for an emergency. They'd been tested. The tests were faked; the diesels run for just a short time at low speed. When the diesels were put through a real test under emergency-like conditions, the crankshaft on the first one snapped in about an hour, then the second and third. We nicknamed the diesels, "Snap, Crackle and Pop."
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(Note: Moments after I wrote that sentence, word came that two of three diesels failed at the Tokai Station as well.)
In the US, we supposedly fixed our diesels after much complaining by the industry. But in Japan, no one tells TEPCO to do anything the Emperor of Electricity doesn't want to do.
I get lots of confidential notes from nuclear industry insiders. One engineer, a big name in the field, is especially concerned that Obama waved the come-hither check to Toshiba and TEPCO to lure them to America. The US has a long history of whistleblowers willing to put themselves on the line to save the public. In our racketeering case in New York, the government only found out about the seismic test fraud because two courageous engineers, Gordon Dick and John Daly, gave our team the documentary evidence.
In Japan, it's simply not done. The culture does not allow the salary men, who work all their lives for one company, to drop the dime.
Not that US law is a wondrous shield: both engineers in the New York case were fired and blacklisted by the industry. Nevertheless, the government (local, state, federal) brought civil racketeering charges against the builders. The jury didn't buy the corporation's excuses and, in the end, the plant was, thankfully, dismantled.
Am I on some kind of xenophobic anti-Nippon crusade? No. In fact, I'm far more frightened by the American operators in the South Texas nuclear project, especially Shaw. Stone & Webster, now the Shaw nuclear division, was also the firm that conspired to fake the EDG tests in New York . (The company's other exploits have been exposed by their former consultant, John Perkins, in his book, "Confessions of an Economic Hit Man.") If the planet wants to shiver, consider this: Toshiba and Shaw have recently signed a deal to become worldwide partners in the construction of nuclear stations.
The other characters involved at the South Texas Plant that Obama is backing should also give you the willies. But as I'm in the middle of investigating the American partners, I'll save that for another day.
So, if we turned to America's own nuclear contractors, would we be safe? Well, two of the melting Japanese reactors, including the one whose building blew sky high, were built by General Electric of the Good Old US of A.
After Texas, you're next. The Obama administration is planning a total of $56 billion in loans for nuclear reactors all over America.
And now, the homicides:
CNN is only interested in body counts, how many workers burnt by radiation, swept away or lost in the explosion. These plants are now releasing radioactive steam into the atmosphere. Be skeptical about the statements that the "levels are not dangerous." These are the same people who said these meltdowns could never happen. Over years, not days, there may be a thousand people, two thousand, ten thousand who will suffer from cancers induced by this radiation.
In my New York investigation, I had the unhappy job of totaling up post-meltdown "morbidity" rates for the county government. It would be irresponsible for me to estimate the number of cancer deaths that will occur from these releases without further information; but it is just plain criminal for the TEPCO shoguns to say that these releases are not dangerous.
Indeed, the fact that residents near the Japanese nuclear plants were not issued iodine pills to keep at the ready shows TEPCO doesn't care who lives and who dies, whether in Japan or the USA. The carcinogenic isotopes that are released at Fukushima are already floating to Seattle with effects we simply cannot measure.
Heaven help us. Because Obama won't.
BBC, 14 March 2011 Last updated at 23:14 GMT
Japan earthquake: New blast at Fukushima nuclear plant
Breaking news
A fresh explosion has been heard at a quake-hit nuclear plant in northern Japan, local media say.
Technicians have been battling to stabilise reactor 2 at the Fukushima Daiichi plant, after two other reactors exploded in three days.
International nuclear watchdogs said there was no sign of a meltdown but one minister said a melting of rods was "highly likely" to be happening. [?!]
The crisis was sparked by a 9.0-magnitude quake and tsunami.
http://www.bbc.co.uk/news/world-middle-east-12307698
A nuclear meltdown is an informal term for a severe nuclear reactor accident that results in core damage from overheating. The term is not officially defined by the International Atomic Energy Agency or by the U.S. Nuclear Regulatory Commission.
A meltdown occurs when a severe failure of a nuclear power plant system prevents proper cooling of the reactor core, to the extent that the nuclear fuel assemblies overheat and melt, either partially or completely. A meltdown is considered very serious because of the potential that radioactive materials could be released into the environment.
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2340: Tokyo Electric officials are now holding a news briefing. They say the blast at reactor 2 happened "near the pressure vessel". They also confirm that some staff at the nuclear power plant are being evacuated.
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2333: More details on the reported blast at Fukushima's reactor 2. The explosion is feared to have damaged the reactor's pressure-suppression system, Kyodo says. It adds that "radiation tops legal limit" after the explosion.
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2320: A spokesperson from Tokyo Electric says said some staff have been evacuated from the site.
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2316: Kyodo now says that the suppression pool may have been damaged at reactor 2.
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2311: The news agency said the blast was heard at 0610 local time on Tuesday (2110 GMT Monday). No other details were immediately announced.
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2308: An explosion is heard at Fukushima's second reactor, the Kyodo news agency reports.
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