Possible reactor meltdown in Japan

[Astro14]

Originally Posted By: IndyIan
Astro14,
So human nature being what it is, for example, my nuclear robotics buddy has seen contractors who think its fun to work with 110V live...
How often do you think a nuclear accident like the one in Japan is going to happen? It's pretty obvious in highsight that a tsunami was very possible at their location, and I'm sure someone brought that possibility up in the design stage, but it seems nothing was done.
I don't have your resume but I think given the external pressure of a company trying to make money on running a plant, short cuts and inspections that aren't very thorough are going to occur.
Also many many reactors are nearing or have exceeded their design age and there is going to be huge pressure to run them longer and longer... As not many countries seem to have the billions needed to build new ones right now.


You raise a lot of interesting issues, to which my answers would be speculative at best...

Look, I have seen the US Navy (your Navy, America's Navy) run about 100 reactors without incident for decades. Yes, we have lost two vehicles, two subs, due to vehicle issues (torpedo explosion and pipe failure) but those are vehicle risks...The Navy is an illustrative example though - we can do it for propulsion efficiencies and don't have to worry about the lawyers suing us to prevent construction.

Nuclear would cost less than half of what it does now to build plants if we didn't have all the lawsuits that delay construction, but even with those, nuclear is still the cheapest form of electricity.

We need a base generation capability that provides electricity near the use point, regardless of weather. Solar can augment, wind can augment (though lots of folks don't want either in their backyards...and solar uses toxic heavy metals in the panel construction...and they both cost more than double what fossil fuels do...).

As far as operating complex machinery for profit while maintaining safety...what do you think the airlines do every day? Technically challenging, dynamic environment, for profit motive...and they have a good safety record (better than driving...that's for sure!)

So it is possible. I have heard that TEPCO asked for waivers on safety regs and operting parameters...if true, that would lead me to believe that they had cut some corners, but even so, that plant withstood an earthquake that exceeded design specs by over 100 times. The reactors shut down automatically as designed, and back-up generators (to keep the cores cooled while decay heat was still being created) kicked in when the grid went down as a result of the quake.

Then the tsunami took out the back-up generators...so, clearly the site design didn't correctly anticipate everything.

So, while I can't comment on the state of various reactors around the world, I know that you can run complex machinery safely. And we need to examine where we get our power to analyze all the costs and all the benefits...

I am just asking for rational thinking, not emotional responses.

 

[Mystic]

Well, things have gotten a lot worse at one of these reactors. Apparently one of the cores has been compromised. A couple of workers stepped into water that had 10,000 times the allowable amount of radiation. They were hospitalized. Japanese officials are calling the situation 'grave and serious.' There is now probably a real possibility that there could be serious contamination.

To think this whole mess could have been avoided if there had been adequate protection for the diesel electric generators. In the end proper protection for those generators and those gnerators themselves will seem very cheap compared to the potential cost of this nuclear mess.

 

[Astro14]

Originally Posted By: Mystic
Well, things have gotten a lot worse at one of these reactors. Apparently one of the cores has been compromised. A couple of workers stepped into water that had 10,000 times the allowable amount of radiation. They were hospitalized. Japanese officials are calling the situation 'grave and serious.' There is now probably a real possibility that there could be serious contamination.

To think this whole mess could have been avoided if there had been adequate protection for the diesel electric generators. In the end proper protection for those generators and those gnerators themselves will seem very cheap compared to the potential cost of this nuclear mess.


Couldn't agree more...the designed-in redundancy failed. Now this is slowly becoming a bigger and bigger mess - one that could have been avoided...

This is tragic in so many ways...And one of the ways in which it is tragic, is that we've all taken focus off the loss of, what is it up to now?, 20,000 people in the tsunami...

 

[OVERKILL]

Originally Posted By: Astro14
Originally Posted By: Mystic
Well, things have gotten a lot worse at one of these reactors. Apparently one of the cores has been compromised. A couple of workers stepped into water that had 10,000 times the allowable amount of radiation. They were hospitalized. Japanese officials are calling the situation 'grave and serious.' There is now probably a real possibility that there could be serious contamination.

To think this whole mess could have been avoided if there had been adequate protection for the diesel electric generators. In the end proper protection for those generators and those gnerators themselves will seem very cheap compared to the potential cost of this nuclear mess.


Couldn't agree more...the designed-in redundancy failed. Now this is slowly becoming a bigger and bigger mess - one that could have been avoided...

This is tragic in so many ways...And one of the ways in which it is tragic, is that we've all taken focus off the loss of, what is it up to now?, 20,000 people in the tsunami...


You see the picture of the piled up kids backpacks? That one hit home the worst for me.

 

[Shannow]

Originally Posted By: IndyIan
Also many many reactors are nearing or have exceeded their design age and there is going to be huge pressure to run them longer and longer... As not many countries seem to have the billions needed to build new ones right now.


Just about every power station in your (and my) country is operating beyond (and sometimes way beyond) their "design" life. And by beyond, I mean really beyond, double and triple their design life.

It doesn't mean that they are unsafe, unless they are allowed to become unsafe. Through rigorous application of engineering and metallurgy, due diligence can be maintained...gets expensive testing and replacing welds, but not everything reaches the end at the same time (eg. welds last half as long as the steam piping).

Remember, GM (OZ) were petitioning the Govt that the "design" life of a Commodore was 80,000km, or 5 years.

 

[Mystic]

I am hoping that somehow they can patch the hole or crack in the core of the reactor that is leaking. There may be more than one that is leaking from the core. If not, some very dangerous levels of radiation and perhaps nasty stuff like Plutonium 239 could get into the ground water and gradually travel about in the subsurface.

The people who build nuclear reactors need to remember how expensive a major disaster will be, even if they do not believe that such a disaster is possible.

The people who build nuclear reactors need to be willing to spend money on the backup systems even if they think those backup systems will never be needed.

 

[Mystic]

Also, the mere fact that apparently a core (or cores) was compromised proves that the material (steel and concrete) to contain the core in the event of a meltdown is not invincible like some may have thought.

The reactor that leaked this very radioactive water is Reactor 3. This is the reactor that had the MOX (Uranium and Plutonium) fuel. Nobody knows how bad this situation is. The Japanese said it was 'grave and serious,' and so far in this situation they had tended to understate the problems. There is even the possibility that Reactor 3 is not the only reactor in this facility with a crack or hole in the core.

The contaminated water from Reactor 3 was in a separate building containing a turbine. So we know that the contamination has spread to some extent. The core in Reactor 3 has been cooled down enough so that it will probably not meltdown. But severely contaminated water from the core can get into the groundwater. And hey, it has already been found in a separate building, away from the nuclear reactor.

I am hoping this situation can be controlled. But I am not very optimistic right now. This entire facility will have to be entombed after they cool these reactors enough.

 

[PandaBear]

Ground water contamination, if it is not from rain water contamination, would means a huge area would be wasteland in the future. What happen is likely a reduction of useful size of the country by 1/4 or so, and such a huge impact could easily put them back into 3rd world status for 10-20 years.

 

[MolaKule]

Quote:
Then the tsunami took out the back-up generators...so, clearly the site design didn't correctly anticipate everything.



I agree with most of what you stated.

As I understand it, the design and siting was based on historical data that showed a Tsunami of certain heights and earthquakes of highest recorded magnitudes.

But to say you can anticipate all occurrances is somewhat unfair.

If a larger than normal meteor had landed on the site, how can you say the design was deficient simply because you had not anticipated a meteor the size of an SUV hitting the nuclear power plant?

 

[Volvo_ST1]

Originally Posted By: MolaKule
If a larger than normal meteor had landed on the site, how can you say the design was deficient simply because you had not anticipated a meteor the size of an SUV hitting the nuclear power plant?



You mean a meteorite. A meteor is only the visible phenomenon. But yes, you just made a good point, supporting the suggestion that any worst case scenario, no matter how unlikely, will happen at least once.

 

[Mystic]

Actually, there have been at least two tsunamis in world history that were at least 100 feet high. This most recent Japanese earthquake generated a tsunami that was about 80 feet high in places. There are estimates that if a major earthquake takes place off the northwest coast of the USA (perhaps I should say when) there could be tsunami waves up to 90 feet high. And one of the major historial tsunamis affected Japan.

So I think there is plenty of historical evidence to support having backup generators housed in facilities at least 100 feet above sea level. At 100 feet above sea level almost no tsunami would be able to reach the backup generators.

 

[Mystic]

They seemed to have backed away somewhat from saying that the core was compromised. They are saying that the water that had radiation 10,000 times higher than normal came from the turbine building somehow. Seems to me it still had to come from the overheated core somehow.

The radioactive Iodine level in the nearby ocean is 1250 times normal levels.

The Japanese had a 12 mile evaucation zone away from this plant. They are encouraging people living as far as 19 miles to evacuate.

 

[Shannow]

That type of reactor has steam that's been in contact with the core passing through the turbines, so that means that there's radioactive "stuff" in the turbines.

Black trip usually has the steam mains drains fail into the open position to stop water entering the turbine, so the condenser will still have radioactive steam entering it for some time after a trip.

 

[Astro14]

Originally Posted By: MolaKule
Quote:
Then the tsunami took out the back-up generators...so, clearly the site design didn't correctly anticipate everything.



I agree with most of what you stated.

As I understand it, the design and siting was based on historical data that showed a Tsunami of certain heights and earthquakes of highest recorded magnitudes.

But to say you can anticipate all occurrances is somewhat unfair.

If a larger than normal meteor had landed on the site, how can you say the design was deficient simply because you had not anticipated a meteor the size of an SUV hitting the nuclear power plant?



Fair enough. And the plants themselves withstood a 9.0 quake when the design spec was 8.2...a difference of over 100 times the severity (if I understand the Richter scale correctly). So, that bit of engineering was well done...

And it is a BWR - so in the cooling alone, there will be water circulating outside the core. It's not like a PWR with a sealed primary loop...

 

[Al]

Originally Posted By: PandaBear
What happen is likely a reduction of useful size of the country by 1/4 or so, and such a huge impact could easily put them back into 3rd world status for 10-20 years.

You are almost as pessimistic as me. I think it will be lucky to stop there.

But keep inmind my credibility is lost bc I spelled "molten" "molton"

 

[mva]

Here is a graphic showing the layout and status of the reactors.

Go to the interactive graphics page:

Layout

Status March 26

 

[MolaKule]

Quote:
You mean a meteorite. A meteor is only the visible phenomenon. But yes, you just made a good point, supporting the suggestion that any worst case scenario, no matter how unlikely, will happen at least once.


I stand corrected as I used the "common" term instead of the strictly scientific term. The correct term for an object in space smaller than an asteroid is meteoroid, whereas a meteor is the light phenomenon which results from the entry of a meteoriod into the Earth's atmosphere.

Another definition of meteor is: "A natural object of extraterrestrial origin (meteoroid) that survives passage through the atmosphere and hits the ground."

The "Tunguska event" in Siberia was calculated to have released 30 Megatons of energy. It was caused by etiher a very large meteoroid or a small comet.

Back to Japan. The Japanese are going to need a lot of help and expertise in mitigating this accident, and I think the hysteria mongers and anti-nukers will attempt to make a real issue of this.

On the positive side, reactor and containment designs will certainly be modified in the future to increase safety and reduce radiation emissions.

As I have stated before, an unrealistic expectation in life is the expectation of zero risk.

 

[Volvo_ST1]

Originally Posted By: MolaKule
Quote:
You mean a meteorite. A meteor is only the visible phenomenon. But yes, you just made a good point, supporting the suggestion that any worst case scenario, no matter how unlikely, will happen at least once.


I stand corrected as I used the "common" term instead of the strictly scientific term. The correct term for an object in space smaller than an asteroid is meteoroid, whereas a meteor is the light phenomenon which results from the entry of a meteoriod into the Earth's atmosphere.


I myself was not correct either. A meteoroid is the object that falls to the ground. A meteorite is that what's left after the impact, if anything is left.

Quote:
Another definition of meteor is: "A natural object of extraterrestrial origin (meteoroid) that survives passage through the atmosphere and hits the ground."


Where did you find that? I need to email them.

 

[Mystic]

I am not anti-nuclear by any means, but we cannot afford a major disaster at a nuclear facility.

In the case of Japan, the earthquake and the tsunami caused tremendous loss of life and damage. It will probably require what would be over 300 billion dollars in American money to repair the damage. But Japan can recover of course from this earthquake and tsunami. It will just take money and time. It may take five years or it may take ten years or twenty years. But of course there will ultimately be recovery.

On the other hand, if things really went south at this nuclear facility, a sizeable area of Japan probably could no longer be inhabited by the Japanese. And Japan is a small country, about the size of California and with a population of over 100 million people.

What really makes me very angry is that in every nuclear crisis we always seem to find out about poor engineering, poor quality construction, shortcuts, mismanagement, lying by officials, etc. Yes, we need nuclear power plants. But no more excuses about poor construction and poor design.

Some of the people who designed this Japanese nuclear facility perhaps should ultimately wind up in prison. Who it their right mind would have located the diesel backup generators where they did. Slipshod design decisions and substandard engineering and workmanship simply are unacceptable when a nuclear facility is built. Yes, we need nuclear facilities. Yes, build nuclear power facilities. But they must be build properly by quality engineers who respect the power of nature and who will not accept poor design, poor quality construction, poor site selection, etc.

If things really went bad at this nuclear facility it could take decades for there to be recovery in a considerable area. That would make the earthquake and tsunami, as terrbile as they were, seem minor in comparison.

 

[Cause4Alarm]

the people who designed the plant in the 50's shouldn't go to jail......thats dumb IMO......the people who run tepco, defiantly need something done to them... if you look look at tepco's history and borderline lies they're saying right now on top of the fact that it's pretty clear they don't wanna say whats happening they shouldn't be allowed to run a microwave nevermind a reactor