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Major Japan Earthquake!

"A volcano in south-western Japan has erupted after nearly two weeks of relative silence, sending ash and rocks up to four kilometres into the air, a local official said.
It was not immediately clear if the eruption was a direct result of the massive 8.9-magnitude earthquake that rocked northern areas on Friday, unleashing a fierce tsunami and sparking fears that more than 10,000 may have been killed.
The 1,421-metre Shinmoedake volcano in the Kirishima range saw its first major eruption for 52 years in January.
There had not been any major activity at the site since March 1.
Authorities have maintained a volcano warning at a level of three out of five, restricting access to the entire mountain.
In April last year, the eruption of the Eyjafjoell volcano in Iceland dispersed a vast cloud of ash, triggering a huge shutdown of airspace that affected more than 100,000 flights and 8 million passengers."


The people of Japan must be wondering why?
This is adding insult to injury!

:kilroy:
 
According to several reports, this blast was much more powerful than the first one and appears to have severely deformed to reactor vessel. Additional reports indicate that the vessel damage is such that they are unable to get any water inside of it(flowing through) and are now flooding the building with sea water in an attempt to cool the vessel. The steam production from this is very high and reportedly contains Cesium & Iodine particulate matter(a very strong indication that a fission reaction is still ongoing despite the reactor SCRAM and cooling attempts). I've heard two retired Nuclear Engineers state that their fear is if the fuel in Fukushima 1 Unit 3(or unit 1) melts to what is known as an uncontrollable geometry, no amount of water will be able to cool the fuel into a static(cold) state. The consequences of such an event are obvious.

I want to point out that this event has gone from a Level 3 Incident classification to a Level 4 Accident in less than 24 hours. It is very likely that this has now changed to a Level 5 or possibly Level 6 Accident but since accurate assessment takes time, it may be 12 to 24 hours before that declaration is made or not.

There is a lot of confusion & mixed reporting coming out of this and adding to the confusion are conflicting reports from different agencies/entities within the Japanese Govt. Getting an accurate picture & information at this point is very difficult.

My Consulting Company has two former US Army NBC Specialists who have a wealth of experience & training background including further training & experience within both the US DOE/NRC and two Nuclear Utilities regarding Safety, Risk Assessment/Planning, & Contamination/Decontamination. Both of them are actively plugged in as consultants directly to business & Govt entities in Japan(pro bono I may add).

If I hear anything, I will try to pass it along.

(Edit), Major news outlets are reporting that Gamma Sensors on the USS Ronald Reagan 160 miles offshore have picked up slightly elevated levels of radiation. The Microsievert (µSv) count per hour on the Reagan was equivalent 1 month's rate of normal background count accumulation.
 
thanks for the update deathfromafar...

Not looking good. Is the risk of damage at Chernobyl proportions or are modern safety measures more capable of containing any major radioactive leaks?
 
kilo delta said:
Not looking good. Is the risk of damage at Chernobyl proportions or are modern safety measures more capable of containing any major radioactive leaks?
Click to expand...

What made the Chernobyl accident so bad was (1) it did not have a containment building and (2) the reactor itself was graphite moderated; the Japanese reactor is a water moderated Westinghouse design. (Both use water for cooling.)

The water moderated reactors would slow down when the water level dropped. But a graphite moderated reactor could instead run away; the reactor power would continue to climb, which would cause the water to boil even more; what finally happened was a BLEVE event (steam explosion) that blew the top off of the reactor, followed by a second explosion caused by a nuclear excusion. That, and the burning graphite in the reactor remains caused the huge release of radiation.

What they are trying to do in Japan right now is cool down the remains of the reactor internals before it compromises the reactor shell. If the shell is compromised, the remaining liquid in the reactor could cause a steam explosion and a release of radioactive steam; the hot core could also melt it's way into the ground and get into the water table.

Neither event would be good; but no where as devestating a release of radioactive material as Chernobyl was. It was the smoke from the burning radioactive graphite fire for two weeks after the explosion that made Chernobyl so bad. Just how bad would depend on the direction and speed the wind is blowing.
 
jhefner said:
What made the Chernobyl accident so bad was (1) it did not have a containment building and (2) the reactor itself was graphite moderated; the Japanese reactor is a water moderated Westinghouse design. (Both use water for cooling.)

The water moderated reactors would slow down when the water level dropped. But a graphite moderated reactor could instead run away; the reactor power would continue to climb, which would cause the water to boil even more; what finally happened was a BLEVE event (steam explosion) that blew the top off of the reactor, followed by a second explosion caused by a nuclear excusion. That, and the burning graphite in the reactor remains caused the huge release of radiation.

What they are trying to do in Japan right now is cool down the remains of the reactor internals before it compromises the reactor shell. If the shell is compromised, the remaining liquid in the reactor could cause a steam explosion and a release of radioactive steam; the hot core could also melt it's way into the ground and get into the water table.

Neither event would be good; but no where as devestating a release of radioactive material as Chernobyl was. It was the smoke from the burning radioactive graphite fire for two weeks after the explosion that made Chernobyl so bad. Just how bad would depend on the direction and speed the wind is blowing.
Click to expand...

Thanks for the explanation. :salute: :)
 
If anyone in the USA at least is worried about nuclear fallout all the way from Japan; please let me point out that the Hydrogen bombs we exploded in the Pacific Atolls released far more radiation than this plant ever could. (The Chernobyl disaster released 100 to 1000 times less radioactivity than nuclear weapons testing during the 1950s and 1960s.)

Japan will depend on the amount released and the speed and direction of the prevailing winds. Four hundred times more radioactive material was released by Chernobyl than had been by the atomic bombing of Hiroshima. Once again, no matter what happens, this plant will not be another Chernobyl.

http://tvnz.co.nz/world-news/japan-quake-another-chernobyl-unlikely-4061904

-James
 
Regarding Fukushima 1, Unit 3, not sure how well known this information is but Unit 3 is fueled with MOX Fuel which is a combination of Uranium and Plutonium Oxide. A Meltdown & atmospheric release from this type of core presents a greater degree of risks.

Still, information is sketchy and each time I hear the lead agencies speak, I hear conflicting information and they seem to be slowly admitting the situation is far worse than originally claimed.
Equally as bothersome is the fact that there has been significant hindrance in getting International Inspectors & Measurement Teams in to get a better picture of what is going on. That plus many other clues are not at all encouraging.

Update: New wires are just reporting an explosion at Unit 2. No further details.

http://abcnews.go.com/International...hima-nuclear-plant-explodes/story?id=13131123
 
jhefner said:
What made the Chernobyl accident so bad was (1) it did not have a containment building and (2) the reactor itself was graphite moderated; the Japanese reactor is a water moderated Westinghouse design. (Both use water for cooling.)
[...]
Click to expand...

From my understanding, an aspect that also contributed to the Chernobyl accident was an intrinsic design-problem of the moderated area of the RBMK reactor core, which left the bottom of the core unmoderated by graphite because there are no graphite packages in that area. The moderation here is done by the light water itself and its volume of flow.
Also the tips of the controlrods were critical, which were made of graphite and had the problem that they initially sped up the nuclear processes when inserted (now that was a major design flaw). This was one factor that contributed to the catastrophic accident there. By the way, the aforementioned BLEVE event (steam explosion) in Chernobyl was gigantic, it lifted the top of the reactor, which weighed over 1000 tons and was 3meter x 17meter in size, up in the air like nothing and flipped it on it's back, so it came to rest on the reactor vessel structure up side down (can be seen on images, with its destroyed fuel, cooling and control tubes sticking out).

I'm no expert by all means, but after reading a lot about the designs of nuclear reactors I come to believe that reactors that rely on the moderation by light water generally have a serious security problem when faced with system failures in the primary water circulation. It's like walking on a knifes edge.

What worries me most in Fukushima is the possibility of breaches in the continment systems, the MOX fuel and in further addition the situation of the over 200 tons of spent fuel rods that are stored in pools in the reactor buildings, that also need heavy cooling. The system of at least one of the pools seems to have failed. As far as I know these pools are ___outside__ the containment structure and have no biological shield.

Oh well. I dearly hope they get it under control, but I fear the worst.

Mark
 
Latest news is that they are (or already have) retreating all staff from the premises (those that are still alive).. which means it is no loner controlled, and hence out of control.

We may all keep hoping things 'will be alright'..... but lets face it, they are not.
 
Myself and three other gentlemen have been working in shifts trying to both supply information and obtain it at the same time. The way many reports coming out of Fukushima have shaped up, it's safe to say that the Japanese Authorities are not being very forthcoming up to now and the security lockdown of the site and information is not unlike what we saw 25 years ago from the Soviets. So we have scavenged as much information from credible second hand sources as possible and more and more, this looking like a worst case scenario. I too have heard the reports the plant has been evacuated but I would call those reports hard to confirm and there are other reports that there are a small number of plant workers and JSDF fighting the blazes. If this is the case then the situation is likely at the point of being a Level 7 Accident like Chernobyl but so far no official of the Japanese Government has declared this. Other Nuclear Agencies of France and Russia had previously indicated this event was more likely a Level 5 or 6 Accident rather than Level 4 claimed by the Government.

This is what I have solid information on. There is low level fallout being detected in Tokyo now and all foreign government embassies have been officially notified of the danger. The radiation measurement reports from in and around the plant are not good. Before now, the Government quoted figures that seemed way too low considering known/recorded comparisons to previous incidents and accidents. I have reports of the hourly doses on site being as high as 1 Sv and as high as 400 mSv per hour outside the plant perimeter(the latter figure now being reported by the Government). Now there is a no fly zone over the site that extends outwards to near the boundaries of the exclusion zone.

It's not encouraging news at all and more and more, the Government is coming around to admitting this may be headed towards a worst case scenario.
 
kilo delta said:
Ditto.

Another question I have. Up until now the reactors are being cooled by sea water in a hastily set up manner. Is the contaminated sea water contained on site or is it being pumped back out to sea?
Click to expand...

I've heard some reports that the discharge went back into the sea but no confirmation. Normal plant operations release discharge back into waterways/sea but that type of discharge is normally exchanger/turbine with minimal to no contamination. Most of the "hot radioactive" water is kept captive for storage/disposal either on site or shipped offsite. The "hot" steam releases under normal operations are usually short duration and the isotopes(very low level) in those are short lived and dispersed quickly.

In the Fukushima situation, being that the heat levels have been very high, it's likely a good bit of the water being pumped in is turning into steam which isn't good either as it can carry isotopes/particulate matter airborne for some distance. This steam/discharge though is without a doubt highly contaminated from byproducts caused by core heat/melting.

PS, I am NOT a Nuclear Expert but in my line of work & past work, I have been through a good bit of related classroom and practical training on the subject matter. I'm sure I have forgotten more than was taught to me! No question it is a very complex & serious business(Nuclear Energy & Nuclear related industry).
 
Francois said:
Yeah, right ........ :blind:
Click to expand...

Don't listen to me then; listen to these:

http://bravenewclimate.com/2011/03/13/fukushima-simple-explanation/

Just a reminder, to keep things in perspective:

* Earthquake and Tsunami -- 10,000(+?) dead, 1800(+?) wounded
* Fukushima Nuclear accident -- 1 dead, <50 wounded?

And this was after a major catastropic event; about the only thing I could think of that may have been worst would have been a direct hit by a jetliner or military aircraft. Granted, the worst is not over. But this is a teachable moment for nuclear power, just like the two space shuttle accidents, not a time to call for them to be shut down.

Life itself carries risk; increasingly, we as a society have become wimps when it comes to risk taking. Aviation and the world we live in was built upon the literal blood and sweat of our forefathers; now we believe everything has to carry zero risk.

What are the alternatives to nuclear power? Fossil generation, with it's emissions and the hazards of mining for coal, fracing for natural gas, or getting oil from deep water wells or the Middle East? Wind, with its unpredictability, spotty availability, and bird strikes by endangered species? Solar, with mining hazards in getting the materials used to build solar panels and it's spotty availability?

Hoover Dam could not be built today because of the environmental damage it caused to the Colorado River. And if you think hydro is risk-free, check this out:

http://www.boston.com/bigpicture/2009/09/the_sayanoshushenskaya_dam_acc.html

A zero risk society is one that achives nothing but a backward slide to the caveman era. The objective should be to minimize risk, not eliminate it altogether. But, in our current, lawsuite happy environment, that is no longer the case.
 
Worse is right. It's classified as a 6 now. 1 higher than Three Mile Island and 1 less than Chernobyl. Things do not look good.

What gets me is the Japanese authorities said there'd be no problems with the Nuc plants. I'm sure they knew something was wrong but kept it quiet as long as they dared.
 
This just went out on Associated Press:

FUKUSHIMA, Japan – Japan suspended operations to prevent a stricken nuclear plant from melting down Wednesday after a surge in radiation made it too dangerous for workers to remain at the facility. Chief Cabinet Secretary Yukio Edano said work on dousing reactors with water was disrupted by the need to withdraw. "So the workers cannot carry out even minimal work at the plant now," Edano said. "Because of the radiation risk, we are on standby."

That is a very ominous sign. With all the overlapping reports today on fires and explosions at different buildings, it's been nearly impossible to get a clear picture of what is really going on.
If the full evacuation of personnel has happened, it is in all likelihood a runaway situation. If opinion matters at this point, I suspect things have or will soon escalate to a Level 7 accident.

My God, I hope I am wrong.
 
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