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Radiation and the Japanese Nuclear Reactors (Nuclear Energy Institute - NEI)
Nuclear Energy Institute (NEI) ^ | Updated 3/13/11 @ 3:30 p.m. EDT | Nuclear Energy Institute (NEI)

Posted on 03/13/2011 10:46:13 PM PDT by SteveH

Radiation and the Japanese Nuclear Reactors

March 2011

Key Facts

* An earthquake measuring 9.0 on the Richter scale struck off the northeastern coast of Japan on March 11, triggering a tsunami. Along with the loss of life and damage, Japan also faces the challenge of stabilizing nuclear power plants in the hardest-hit region.

* After the earthquake, all the operating reactors at the Fukushima Daiichi and Fukushima Daini nuclear plants shut down automatically, as they are designed to do. However, due to the loss of offsite power and failure of the backup diesel generators, there were difficulties powering the waste heat cooling systems at the Fukushima Daiichi plant.

* To reduce the resulting increase in containment pressure, Tokyo Electric Power Co., vented steam—containing small amounts of radioactive material—from the primary cooling circuit of reactors 1 and 3. The released vapor passed though filters designed to remove radioactive components such as iodine and cesium. Upon release, the slightly radioactive vapor dispersed into the atmosphere.

* Residents have been evacuated from a 12.5-mile radius around the Daiichi plant and about two miles around the Daini plant. The precautionary measures taken to evacuate residents near the sites are intended to prevent or mitigate any radiation dose from radiation releases that might occur as the situation develops.

* A buildup of hydrogen gas in the secondary containment structure at Daiichi Unit 1 led to an explosion at that reactor (see reactor diagram). However, the integrity of the primary containment structure was not compromised and there were no large leaks of radiation from the reactor core.

Radiation Measurements

The U.S. Nuclear Regulatory Commission’s (NRC) annual limit for worker exposure to radiation is 5,000 millirems (mrems). The average U.S. nuclear power plant worker receives 120 mrems annually. A typical X-ray provides 10 mrems per film.

The NRC’s public radiation dose limit is 100 mrems annually. The average U.S. public exposure from the commercial nuclear fuel cycle, including nuclear power plant operations, is less than 1 mrem per year.

The average American receives more than 600 millirems of radiation exposure annually—about half from naturally-occurring sources and the rest from medical applications, such as CT scans and X-rays. Although there is scientific evidence for health risks following high-dose radiation exposures, risks of health effects are either too small to be observed or are nonexistent at levels below 5,000–10,000 mrem. [1]

A small amount of radiation was released in the 1979 Three Mile Island accident in Pennsylvania, but studies found that it did not have an impact on health or the environment. About half of the reactor fuel at TMI Unit 2 melted during the early stages of that accident.

--- [1] Position Statement of the Health Physics Society, “Radiation Risk in Perspective,” U.S. Health Physics Society, July 2010.

TOPICS: Extended News; Japan; News/Current Events
KEYWORDS: bwr; fukushima
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GE has referred questions concerning the Fukushima BWRs to NEI
1 posted on 03/13/2011 10:46:18 PM PDT by SteveH
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To: SteveH
This article linked below may appear to be scare mongering to some, but it does contain some interesting information. Will extract some of the interesting points.

At the 40-year-old Fukushima Daiichi unit 1, where an explosion Saturday destroyed a building housing the reactor, the spent fuel pool, in accordance with General Electric’s design, is placed above the reactor. Tokyo Electric said it was trying to figure out how to maintain water levels in the pools, indicating that the normal safety systems there had failed, too. Failure to keep adequate water levels in a pool would lead to a catastrophic fire, said nuclear experts, some of whom think that unit 1’s pool may now be outside.

Victor Gilinsky, a former commissioner at the Nuclear Regulatory Commission, said that to produce hydrogen, temperatures in the reactor core had to be well over 2,000 degrees and as high as 4,000 degrees Fahrenheit. He said a substantial amount of fuel had to be exposed at least at some point.

“That’s the significance of the hydrogen — it means there was serious fuel damage and probably melting,” said Gilinsky, who was at the NRC when Pennsylvania’s Three Mile Island reactor had a partial meltdown in 1979. “How much? We won’t know for a long time. At TMI we didn’t know for five years, until the vessels were opened. It was a shock.”

The Fukushima Daiichi unit 3, once capable of generating 784 megawatts of power, is substantially bigger than unit 1, which generated about 460 megawatts. As a result, lowering temperatures in its reactor core could prove a much tougher task, experts said.

Japanese officials were also trying to figure out whether Friday’s earthquake, or the subsequent high pressures and temperatures in the reactors, had caused other cracks or leaks in reactors in the region. So far officials have not said that they have found any, though they have noted still unexplained losses of water in some reactor vessels.

At two reactors, a race to contain meltdowns

2 posted on 03/13/2011 11:10:28 PM PDT by justa-hairyape
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To: justa-hairyape
Thanks and I see what you mean. Since it contains new info (albeit from the Wash. Post, so standard caveats presumably apply) and the source is distinct from an industry consortium, hope no one minds that I took the liberty of posting it as a separate thread here

3 posted on 03/14/2011 1:03:19 AM PDT by SteveH (First they ignore you. Then they laugh at you. Then they fight you. Then you win.)
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To: SteveH

Well that thread is gonna get some interesting posts. They do quote some experts though. Would be interesting to debate the points, especially the steroids comment, although I think that was obviously over the top.

4 posted on 03/14/2011 1:10:19 AM PDT by justa-hairyape
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To: justa-hairyape

I posted this on another thread but will dare to post it again here. Seems to explain very clearly why things can go to hell even without a reactor core meltdown. The authorm, “B.Z.” explains at the Survivalblog link his credentials and he knows what he’s talking about.

Found this on the Ticker Forum thread, it’s from Survivalblog. Note that the article (below is an excerpt) was written and posted by Rawles in September; it is in connection with loss of grid power from an EMP or severe solar storm. But the situation is the same, whatever the loss of power is from. He explains very clearly why there is no need of a core meltdown to have a very bad radiation leak. From everything I have read (and it has been obsessive for 2 days at least), it looks as though this is exactly what is happening at the Fukushima nuke plant.

TF link:

Survivalblog link:

Effects of an EMP Attack or Severe Solar Storm on Nuclear Power Plants, by B.Z.

You might ask, “well, if the containment structure can contain the melted reactor core, is there a real danger to the public?” The answer is, “yes,” but not from where you think. The reactor core may well be the focus of most people, but the real concern is somewhere else.

What many people don’t know about nuclear power plants is that when spent fuel is off-loaded from the reactor core, the fuel is then placed into what is essentially a large, very deep swimming pool called the “spent fuel pool.” Fuel that has been removed from an operating reactor core is still very hot (both in the sense of temperature and radiation level). In fact, if you were to stand within even 50 feet of a spent fuel assembly with no shielding, you would receive a lethal dose of radiation in just seconds. The water in the spent fuel pool, in addition to cooling the fuel assemblies, acts as a biological shield. In fact, water is an excellent shielding material. You can stand at the top of the spent fuel pool in virtually any nuclear power plant in the US and receive virtually no dose of radiation, so long as the fuel assemblies are covered by about 25 feet of water.

The building that houses the spent fuel pools at nuclear power plants in this country is usually a simple building, with concrete sides and floors but usually with nothing but a thin, corrugated steel roof. This is the root of the problem. Just like the fuel in the reactor, the fuel assemblies in the spent fuel in pool must also be cooled. These pools have their own independent, multiply redundant systems for cooling, separate from the systems that cool the reactor core. However, these pool cooling systems can be cross-tied with the reactor cooling systems in an emergency. The water in the spent fuel pool must be continuously circulated through heat exchangers (again, like your car radiator) to reject heat. Loss of off-site power will also cause a loss of spent fuel cooling. Normally, the temperature in these spent fuel pools is somewhere around 100 to 110 degrees F or so (similar to a typical suburban “hot tub”). When the spent fuel cooling system pumps stop operating, the fuel assemblies in the spent fuel pool will immediately begin to heat up. These fuel assemblies will continue to heat the water in the spent fuel pool until it boils. The best case scenario of “time to boil” for these spent fuel pools is perhaps 90 hours. The worst case, such as just after a core offload, would be much shorter, perhaps as little as four hours or even less. At that point, once the fuel assemblies in the spent fuel pool become uncovered because the water has boiled off, the effects mirror what would happen in the reactor core. The spent fuel assemblies will heat up until the fuel cladding starts to melt. As bits of the melting fuel fall into what is left of the water in the pool, the process will just accelerate as the heat source is now more concentrated since it has fallen back into the water and the water may flash to steam and this may cause the pressure in the building to increase, and radioactive steam, carrying radioactive particles, will now begin to exit the building through the non-sealed penetrations, portals or doors in the building.

Of course, there are usually multiple sources of water than can be called upon to re-fill the spent fuel pool before the water all boils off. But virtually all of these systems are dependent upon working, electrically operated pumps to move this water. If control systems have failed due to the EMP and there is no power to operate the pumps (either to add additional water or to pump water through the heat exchangers), then the fuel will ultimately become uncovered. Exposing the hot zirconium fuel cladding to air and steam causes an exothermic reaction, and the cladding will actually catch fire at about 1,000 degrees C. Even the NRC concedes that this type of fire cannot be extinguished, and could rage for days (Source: Bulletin of the Atomic Scientists, Vol. 58, No. 1, Jan./Feb. 2002).

The bottom-line is that if the spent fuel cooling pumps cannot be operated or the system cannot be cross-tied with the reactor shutdown cooling system, then the fuel assemblies in the spent fuel pool will melt, catch fire, and radioactive fission products will be released into the atmosphere and much of the countryside downwind of the nuclear power plant will be contaminated for many years.

5 posted on 03/14/2011 1:31:36 AM PDT by little jeremiah (Courage is not simply one of the virtues, but the form of every virtue at the testing point. CSLewis)
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To: SteveH

well if they’re losing water, then they’ve got themselves (or, we’ve got ourselves) a cracked pan and that is a big problem - you can’t just walk in and concrete it up

6 posted on 03/14/2011 1:36:21 AM PDT by blueplum
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To: blueplum

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.
I am writing this text (Mar 12) to give you some peace of mind regarding some of the troubles in Japan, that is the safety of Japan’s nuclear reactors. Up front, the situation is serious, but under control. And this text is long! But you will know more about nuclear power plants after reading it than all journalists on this planet put together.
There was and will *not* be any significant release of radioactivity.
By “significant” I mean a level of radiation of more than what you would receive on – say – a long distance flight, or drinking a glass of beer that comes from certain areas with high levels of natural background radiation.
I have been reading every news release on the incident since the earthquake. There has not been one single (!) report that was accurate and free of errors (and part of that problem is also a weakness in the Japanese crisis communication). By “not free of errors” I do not refer to tendentious anti-nuclear journalism – that is quite normal these days. By “not free of errors” I mean blatant errors regarding physics and natural law, as well as gross misinterpretation of facts, due to an obvious lack of fundamental and basic understanding of the way nuclear reactors are build and operated. I have read a 3 page report on CNN where every single paragraph contained an error.
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 so called Boiling Water Reactors, or BWR for short. Boiling Water Reactors are similar to a pressure cooker. 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 send back to be heated by the nuclear fuel. The pressure cooker operates at about 250 °C.
The nuclear fuel is uranium oxide. Uranium oxide is a ceramic with a very high melting point of about 3000 °C. The fuel is manufactured in pellets (think little cylinders the size of Lego bricks). Those pieces are then put into a long tube made of Zircaloy with a melting point of 2200 °C, and sealed tight. The assembly is called a fuel rod. These fuel rods are then put together to form larger packages, and a number of these packages are then put into the reactor. All these packages together are referred to as “the core”.
The Zircaloy casing is the first containment. It separates the radioactive fuel from the rest of the world.
The core is then placed in the “pressure vessels”. That is the pressure cooker we talked about before. The pressure vessels is the second containment. This is one sturdy piece of a pot, designed to safely contain the core for temperatures several hundred °C. That covers the scenarios where cooling can be restored at some point.
The entire “hardware” of the nuclear reactor – the pressure vessel and all pipes, pumps, coolant (water) reserves, are then encased in the third containment. The third containment is a hermetically (air tight) sealed, very thick bubble of the strongest steel. The third containment is designed, built and tested for one single purpose: To contain, indefinitely, a complete core meltdown. For that purpose, a large and thick concrete basin is cast under the pressure vessel (the second containment), which is filled with graphite, all inside the third containment. This is the so-called “core catcher”. If the core melts and the pressure vessel bursts (and eventually melts), it will catch the molten fuel and everything else. It is built in such a way that the nuclear fuel will be spread out, so it can cool down.
This third containment is then surrounded by 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 explosion, but more to that later).
Fundamentals of nuclear reactions
The uranium fuel generates heat by nuclear fission. Big uranium atoms are split into smaller atoms. That generates heat plus neutrons (one of the particles that forms an atom). When the neutron hits another uranium atom, that splits, generating more neutrons and so on. That is called the nuclear chain reaction.
Now, just packing a lot of fuel rods next to each other would quickly lead to overheating and after about 45 minutes to a melting of the fuel rods. It is worth mentioning at this point that the nuclear fuel in a reactor can *never* cause a nuclear explosion the type of a nuclear bomb. Building a nuclear bomb is actually quite difficult (ask Iran). In Chernobyl, the explosion was caused by excessive pressure buildup, hydrogen explosion and rupture of all containments, propelling molten core material into the environment (a “dirty bomb”). Why that did not and will not happen in Japan, further below.
In order to control the nuclear chain reaction, the reactor operators use so-called “control rods”. The control rods absorb the neutrons and kill the chain reaction instantaneously. A nuclear reactor is built in such a way, that when operating normally, you take out all the control rods. The coolant water then takes away the heat (and converts it into steam and electricity) at the same rate as the core produces it. And you have a lot of leeway around the standard operating point of 250°C.
The challenge is that after inserting the rods and stopping the chain reaction, the core still keeps producing heat. The uranium “stopped” the chain reaction. But a number of intermediate radioactive elements are created by the uranium during its fission process, most notably Cesium and Iodine isotopes, i.e. radioactive versions of these elements that will eventually split up into smaller atoms and not be radioactive anymore. Those elements keep decaying and producing heat. Because they are not regenerated any longer from the uranium (the uranium stopped decaying after the control rods were put in), they get less and less, and so the core cools down over a matter of days, until those intermediate radioactive elements are used up.
This residual heat is causing the headaches right now.
So the first “type” of radioactive material is the uranium in the fuel rods, plus the intermediate radioactive elements that the uranium splits into, also inside the fuel rod (Cesium and Iodine).
There is a second type of radioactive material created, outside the fuel rods. The big main difference up front: Those radioactive materials have a very short half-life, that means that they decay very fast and split into non-radioactive materials. By fast I mean seconds. So if these radioactive materials are released into the environment, yes, radioactivity was released, but no, it is not dangerous, at all. Why? By the time you spelled “R-A-D-I-O-N-U-C-L-I-D-E”, they will be harmless, because they will have split up into non radioactive elements. Those radioactive elements are N-16, the radioactive isotope (or version) of nitrogen (air). The others are noble gases such as Xenon. But where do they come from? When the uranium splits, it generates a neutron (see above). Most of these neutrons will hit other uranium atoms and keep the nuclear chain reaction going. But some will leave the fuel rod and hit the water molecules, or the air that is in the water. Then, a non-radioactive element can “capture” the neutron. It becomes radioactive. As described above, it will quickly (seconds) get rid again of the neutron to return to its former beautiful self.
This second “type” of radiation is very important when we talk about the radioactivity being released into the environment later on.
What happened at Fukushima
I will try to summarize the main facts. The earthquake that hit Japan was 7 times more powerful than the worst earthquake the nuclear power plant was built for (the Richter scale works logarithmically; the difference between the 8.2 that the plants were built for and the 8.9 that happened is 7 times, not 0.7). So the first hooray for Japanese engineering, everything held up.
When the earthquake hit with 8.9, the nuclear reactors all went into automatic shutdown. Within seconds after the earthquake started, the control rods had been inserted into the core and nuclear chain reaction of the uranium stopped. Now, the cooling system has to carry away the residual heat. The residual heat load is about 3% of the heat load under normal operating conditions.
The earthquake destroyed the external power supply of the nuclear reactor. That is one of the most serious accidents for a nuclear power plant, and accordingly, a “plant black out” receives a lot of attention when designing backup systems. The power is needed to keep the coolant pumps working. Since the power plant had been shut down, it cannot produce any electricity by itself any more.
Things were going well for an hour. One set of multiple sets of emergency Diesel power generators kicked in and provided the electricity that was needed. Then the Tsunami came, much bigger than people had expected when building the power plant (see above, factor 7). The tsunami took out all multiple sets of backup Diesel generators.
When designing a nuclear power plant, engineers follow a philosophy called “Defense of Depth”. That means that you first build everything to withstand the worst catastrophe you can imagine, and then design the plant in such a way that it can still handle one system failure (that you thought could never happen) after the other. A tsunami taking out all backup power in one swift strike is such a scenario. The last line of defense is putting everything into the third containment (see above), that will keep everything, whatever the mess, control rods in our out, core molten or not, inside the reactor.
When the diesel generators were gone, the reactor operators switched to emergency battery power. The batteries were designed as one of the backups to the backups, to provide power for cooling the core for 8 hours. And they did.
Within the 8 hours, another power source had to be found and connected to the power plant. The power grid was down due to the earthquake. The diesel generators were destroyed by the tsunami. So mobile diesel generators were trucked in.
This is where things started to go seriously wrong. The external power generators could not be connected to the power plant (the plugs did not fit). So after the batteries ran out, 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”. It is again a step along the “Depth of Defense” lines. The power to the cooling systems should never have failed completely, but it did, so they “retreat” to the next line of defense. All of this, however shocking it seems to us, is part of the day-to-day training you go through as an operator, right through to managing a core meltdown.
It was at this stage that people started to talk about core meltdown. Because at the end of the day, if cooling cannot be restored, the core will eventually melt (after hours or days), and the last line of defense, the core catcher and third containment, would come into play.
But the goal at this stage was to manage the core while it was heating up, and ensure that the first containment (the Zircaloy tubes that contains the nuclear fuel), as well as the second containment (our pressure cooker) remain intact and operational for as long as possible, to give the engineers time to fix the cooling systems.
Because cooling the core is such a big deal, the reactor has a number of cooling systems, each in multiple versions (the reactor water cleanup system, the decay heat removal, the reactor core isolating cooling, the standby liquid cooling system, and the emergency core cooling system). Which one failed when or did not fail is not clear at this point in time.
So imagine our pressure cooker on the stove, heat on low, but on. The operators use whatever cooling system capacity they have to get rid of as much heat as possible, but the pressure starts building up. The priority now is to maintain integrity of the first containment (keep temperature of the fuel rods below 2200°C), as well as the second containment, the pressure cooker. In order to maintain integrity of the pressure cooker (the second containment), the pressure has to be released from time to time. Because the ability to do that in an emergency is so important, the reactor has 11 pressure release valves. The operators now started venting steam from time to time to control the pressure. The temperature at this stage was about 550°C.
This is when the reports about “radiation leakage” starting coming in. I believe I explained above why venting the steam is theoretically the same as releasing radiation into the environment, but why it was and is not dangerous. The radioactive nitrogen as well as the noble gases do not pose a threat to human health.

At some stage during this venting, the explosion occurred. The explosion took place outside of the third containment (our “last line of defense”), and the reactor building. Remember that the reactor building has no function in keeping the radioactivity contained. It is not entirely clear yet what has happened, but this is the likely scenario: The operators decided to vent the steam from the pressure vessel not directly into the environment, but into the space between the third containment and the reactor building (to give the radioactivity in the steam more time to subside). The problem is that at the high temperatures that the core had reached at this stage, water molecules can “disassociate” into oxygen and hydrogen – an explosive mixture. And it did explode, outside the third containment, damaging the reactor building around. It was that sort of explosion, but inside the pressure vessel (because it was badly designed and not managed properly by the operators) that lead to the explosion of Chernobyl. This was never a risk at Fukushima. The problem of hydrogen-oxygen formation is one of the biggies when you design a power plant (if you are not Soviet, that is), so the reactor is build and operated in a way it cannot happen inside the containment. It happened outside, which was not intended but a possible scenario and OK, because it did not pose a risk for the containment.
So the pressure was under control, as steam was vented. Now, if you keep boiling your pot, the problem is that the water level will keep falling and falling. The core is covered by several meters of water in order to allow for some time to pass (hours, days) before it gets exposed. Once the rods start to be exposed at the top, the exposed parts will reach the critical temperature of 2200 °C after about 45 minutes. This is when the first containment, the Zircaloy tube, would fail.
And this started to happen. The cooling could not be restored before there was some (very limited, but still) damage to the casing of some of the fuel. The nuclear material itself was still intact, but the surrounding Zircaloy shell had started melting. What happened now is that some of the byproducts of the uranium decay – radioactive Cesium and Iodine – started to mix with the steam. The big problem, uranium, was still under control, because the uranium oxide rods were good until 3000 °C. It is confirmed that a very small amount of Cesium and Iodine was measured in the steam that was released into the atmosphere.
It seems this was the “go signal” for a major plan B. The small amounts of Cesium that were measured told the operators that the first containment on one of the rods somewhere was about to give. The Plan A had been to restore one of the regular cooling systems to the core. Why that failed is unclear. One plausible explanation is that the tsunami also took away / polluted all the clean water needed for the regular cooling systems.
The water used in the cooling system is very clean, demineralized (like distilled) water. The reason to use pure water is the above mentioned activation by the neutrons from the Uranium: Pure water does not get activated much, so stays practically radioactive-free. Dirt or salt in the water will absorb the neutrons quicker, becoming more radioactive. This has no effect whatsoever on the core – it does not care what it is cooled by. But it makes life more difficult for the operators and mechanics when they have to deal with activated (i.e. slightly radioactive) water.
But Plan A had failed – cooling systems down or additional clean water unavailable – so Plan B came into effect. This is what it looks like happened:
In order to prevent a core meltdown, the operators started to use sea water to cool the core. I am not quite sure if they flooded our pressure cooker with it (the second containment), or if they flooded the third containment, immersing the pressure cooker. But that is not relevant for us.
The point is that the nuclear fuel has now been cooled down. Because the chain reaction has been stopped a long time ago, there is only very little residual heat being produced now. The large amount of cooling water that has been used is sufficient to take up that heat. Because it is a lot of water, the core does not produce sufficient heat any more to produce any significant pressure. Also, boric acid has been added to the seawater. Boric acid is “liquid control rod”. Whatever decay is still going on, the Boron will capture the neutrons and further speed up the cooling down of the core.
The plant came close to a core meltdown. Here is the worst-case scenario that was avoided: If the seawater could not have been used for treatment, the operators would have continued to vent the water steam to avoid pressure buildup. The third containment would then have been completely sealed to allow the core meltdown to happen without releasing radioactive material. After the meltdown, there would have been a waiting period for the intermediate radioactive materials to decay inside the reactor, and all radioactive particles to settle on a surface inside the containment. The cooling system would have been restored eventually, and the molten core cooled to a manageable temperature. The containment would have been cleaned up on the inside. Then a messy job of removing the molten core from the containment would have begun, packing the (now solid again) fuel bit by bit into transportation containers to be shipped to processing plants. Depending on the damage, the block of the plant would then either be repaired or dismantled.
Now, where does that leave us?
• The plant is safe now and will stay safe.
• Japan is looking at an INES Level 4 Accident: Nuclear accident with local consequences. That is bad for the company that owns the plant, but not for anyone else.
• Some radiation was released when the pressure vessel was vented. All radioactive isotopes from the activated steam have gone (decayed). A very small amount of Cesium was released, as well as Iodine. If you were sitting on top of the plants’ chimney when they were venting, you should probably give up smoking to return to your former life expectancy. The Cesium and Iodine isotopes were carried out to the sea and will never be seen again.
• There was some limited damage to the first containment. That means that some amounts of radioactive Cesium and Iodine will also be released into the cooling water, but no Uranium or other nasty stuff (the Uranium oxide does not “dissolve” in the water). There are facilities for treating the cooling water inside the third containment. The radioactive Cesium and Iodine will be removed there and eventually stored as radioactive waste in terminal storage.
• The seawater used as cooling water will be activated to some degree. Because the control rods are fully inserted, the Uranium chain reaction is not happening. That means the “main” nuclear reaction is not happening, thus not contributing to the activation. The intermediate radioactive materials (Cesium and Iodine) are also almost gone at this stage, because the Uranium decay was stopped a long time ago. This further reduces the activation. The bottom line is that there will be some low level of activation of the seawater, which will also be removed by the treatment facilities.
• The seawater will then be replaced over time with the “normal” cooling water
• The reactor core will then be dismantled and transported to a processing facility, just like during a regular fuel change.
• Fuel rods and the entire plant will be checked for potential damage. This will take about 4-5 years.
• The safety systems on all Japanese plants will be upgraded to withstand a 9.0 earthquake and tsunami (or worse)
• I believe the most significant problem will be a prolonged power shortage. About half of Japan’s nuclear reactors will probably have to be inspected, reducing the nation’s power generating capacity by 15%. This will probably be covered by running gas power plants that are usually only used for peak loads to cover some of the base load as well. That will increase your electricity bill, as well as lead to potential power shortages during peak demand, in Japan.
If you want to stay informed, please forget the usual media outlets and consult the following websites:

7 posted on 03/14/2011 2:52:22 AM PDT by Elkiejg (Democrats/Liberals/progressives are EVIL!!)
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To: little jeremiah

That’s very clearly written—and yes, worrisome, despite the “everything’s under control” posts from some FReepers here.

8 posted on 03/14/2011 3:12:53 AM PDT by 9YearLurker
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To: 9YearLurker

The entire article on Survivalblog is very interesting.

What is amazing to me is the number of people responding to me (on another thread) that any concern over the spent fuel rods heating up is completely wrong, and nothing harmful or dangerous can possibly happen.

I don’t get it. Can’t they read? They think the scenario is wrong? That a nuclear engineer with 30 yrs in the field is totally off? I want to hear how he’s wrong, in detail. From everything I can gather, nuclear power plants are not designed for being off grid for more than the amount of time their diesel generators can run. And these plants have no diesel generators to run them at all. And no power to connect to.

9 posted on 03/14/2011 3:26:25 AM PDT by little jeremiah (Courage is not simply one of the virtues, but the form of every virtue at the testing point. CSLewis)
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To: 9YearLurker; little jeremiah
That's very clearly written--and yes, worrisome, despite the "everything's under control" posts from some FReepers here.

Misinformation. There are no reliable sources saying that there is danger from the spent fuel rods. There is no evidence that spent fuel rods can catch on fire. They can get hot for sure and need some cooling depending on how closely they are stored (a single rod can be stored dry).

10 posted on 03/14/2011 3:34:03 AM PDT by palmer (Cooperating with Obama = helping him extend the depression and implement socialism.)
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To: justa-hairyape
At the 40-year-old Fukushima Daiichi unit 1, where an explosion Saturday destroyed a building housing the reactor, the spent fuel pool, in accordance with General Electric’s design, is placed above the reactor.

This is simply not true. There is a pool in the reactor building that is used for rod storage during refueling but long term storage is done at another location on another part of the campus. Since there was no refueling going on for units 1 or 3 there is no fuel stored in these pools.

11 posted on 03/14/2011 3:36:05 AM PDT by Straight Vermonter (Posting from deep behind the Maple Curtain)
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To: little jeremiah
Your author writes junk like "I have recently been in contact with a member of the intelligence community who is highly knowledgeable in the area of EMP." and you expect us to take him seriously? Gimme a break.

12 posted on 03/14/2011 3:36:56 AM PDT by palmer (Cooperating with Obama = helping him extend the depression and implement socialism.)
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To: SteveH; DoughtyOne
To put things into "nookier disaster that will threaten the world" perspective, this would be a good place to post what I had posted earlier when I said this was no Chernobyl and that even Chernobyl was no Chernobyl, to which I got the following response followed by my reply:
-—————Tell that to the parents of the children who developed cancer.

Ah, yes, the children. The magical touchstone of "it doesn't matter what we have to do and how many people it harms if it will save the life of one child."

How about all the parents whose children were harmed because of unnecessarily evacuating tens of thousands of people from the surrounding region? Besides, there wasn't an increase in childhood cancer deaths from Chernobyl. You'll notice that there was screening 2 to 4 years post-Chernobyl for thyroid cancer that showed an increase but that was due to intensive screening detecting what would always have been there but not diagnosed for one reason or another. Also, the latency period for developing thyroid cancer from such a cause is 10 years, so screening 2 to 4 years after the incident would not have spotted the cancers from this cause. Look at what was actually discovered over the decades since Chernobyl versus what the fear-mongers were hyping at the time. Follow the links I posted to the UNSCEAR report fielded by Z. Jawoworski.

The human tragedy of Chernobyl was caused, not by Chernobyl, but by the activists promoting government action where none was needed:
Besides the 28 fatalities among rescue workers and employees of the power station due to very high doses of radiation (2.9 – 16 Gy), and 3 deaths due to other reasons (UNSCEAR 2000b), the only real adverse health consequences of the Chernobyl catastrophe among approximately five million people living in the contaminated regions were the epidemics of psychosomatic afflictions that appear as diseases of the digestive and circulatory systems and other post-traumatic stress disorders such as sleep disturbance, headache, depression, anxiety, escapism, “learned helplessness”, unwillingness to cooperate, overdependence, alcohol and drug abuse and suicides. These diseases and disturbances could not have been due to the minute irradiation doses from the Chernobyl fallout (average dose rate of about 1 – 2 mSv/year), but they were caused by radiophobia (an deliberately induced fear of radiation) aggravated by wrongheaded administrative decisions and even, paradoxically, by increased medical attention which leads to diagnosis of subclinical changes that persistently hold the attention of the patient. Bad administrative decisions made several million people believe that they were “victims of Chernobyl” although the average annual dose they received from “Chernobyl” radiation was only about one third of the average natural dose. This was the main factor responsible for the economic losses caused by the Chernobyl catastrophe, estimated to have reached $148 billion by 2000 for the Ukraine and to reach $235 billion by 2016 for Belarus.
Observations on the Chernobyl Disaster and LNT
See also:
Additional reasons why this is not Chernobyl ...

And even if it had been Chernobyl, Chernobyl was one of the most overhyped disasters until global warming came along.

As I pointed out earlier on another thread:
When are we going to find out the truth and how much radiation is in the jet stream?

Please try to find Before It's Too Late: A Scientist's Case FOR Nuclear Energy by Bernard Cohen. You can get a used one from Amazon for a few dollars. This will put the risks of everything into perspective so you won't be tormenting yourself with images that have little basis in fact. You do know, don't you, that a typical coal-fired plant puts out as waste many tons of radioactive materials per year? And that even if one of the Japanese nuclear plants (light water reactors) completely blew up, it would be, compared to Chernobyl (a graphite core that could burn), like a kid taking a leak against the side of the garage of a house by a river compared to a dam breaking upstream, and that Chernobyl (see reference 4), despite the 31 early deaths of people working at the plant over the next four years, didn't result in a huge number or even a moderately large number of deaths in the surrounding countryside and that the major portion of deaths from Chernobyl was caused by moving people away, giving them a stipend, and their dying from alcoholism as a result or by unnecessary abortions?

Did you know that there are places throughout the world where people have lived for thousands of years that have levels of naturally-occurring radiation that are hundreds of times greater than you could ever receive from a popped nuclear electric plant in Japan (much less Chernobyl) without any statistically higher incidence of cancer? (See also CHERNOBYL: THE FEAR OF THE UNKNOWN by Z. Jawoworksi and "Observations on the Chernobyl Disaster and LNT?" Z. Jawoworski, Dose-Response, 2010, and Nuclear Weapons and Radiation: Miscellaneous Facts, John Moore (look for the part titled "Beneficial Radiation and Regulations."

13 posted on 03/14/2011 3:51:47 AM PDT by aruanan
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To: little jeremiah
I don’t get it.

The responses are pretty clear, which parts don't you get?

They think the scenario is wrong?

First, this isn't an EMP, so yeah, different scenario. Second are the objections to the facts about:
- storage of spent fuel above the reactor

lack of water for cooling or means to use it at the sites where they are currently using seawater for cooling.

Other than that...

14 posted on 03/14/2011 4:14:28 AM PDT by D-fendr (Deus non alligatur sacramentis sed nos alligamur.)
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To: palmer

According to you, this morning’s Washington Post issue is complete bunk too.

15 posted on 03/14/2011 4:39:54 AM PDT by 9YearLurker
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To: 9YearLurker


16 posted on 03/14/2011 4:40:18 AM PDT by 9YearLurker
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To: Straight Vermonter

GE BWR plants store the spent fuel in the reactor building.

17 posted on 03/14/2011 5:05:13 AM PDT by nin_kasi
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To: 9YearLurker
Yes, and I already said so: /focus/news/2688393/posts?page=36#36
18 posted on 03/14/2011 5:30:48 AM PDT by palmer (Cooperating with Obama = helping him extend the depression and implement socialism.)
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To: palmer

That’s what I was referencing.

See-no-evil, hear-no-evil, (”everything’s under control”) posters here make me more nervous for the technology than if it didn’t have such knee-jerk defenders.

19 posted on 03/14/2011 5:35:22 AM PDT by 9YearLurker
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To: 9YearLurker

Same here.

20 posted on 03/14/2011 5:37:26 AM PDT by Tolsti2
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