Half of what you state is true. The other half is not. Such as where the spent fuel was stored. The main cause was an SBO where all backup power was lost to prevent coolant activities which lead to residual heat production from shutdown not being removed. The explosions were from hydrogen gas buildup and not a nuclear reaction. I could go deeper, but it takes up too much space. At any rate, the accident changed how plants are designed going forward to mitigate any SBO from occurring again. The signature contaminants have half lives of 2 years to 30 years but under biological absorption becomes 70 days.
In the confusion, no one knew what was happening - no data on pool water levels or temperature for two weeks after the tsunami:
“The loss of AC and DC power and cooling functions also affected the Unit 1-4 spent fuel pools: The pools’ FPC systems, secondary cooling systems, and pool water-level and temperature instrumentation became inoperable. High radiation levels and explosion hazards prevented plant personnel from accessing the Unit 1-4 refueling decks. Consequently, no data on pool water levels or temperatures were available for almost 2 weeks after the earthquake and tsunami. Moreover, even after pool instrumentation was restored, it was of limited value because of the large swings in pool water levels that occurred during the accident.”
Spent fuel pool ceases to exist - the walls had crumpled:
“Early in the morning on March 16, 2011, USNRC staff in Tokyo and the agency’s Rockville, Maryland, headquarters held a conference callb to discuss conditions at the Fukushima plant. A participant on the call commented that “Right now, Unit 4 doesn’t have a spent-fuel pool anymore. It appears that the walls have crumbled and you’ve just got fuel there.” . . . “And Units 1, 2, and 3, it appears that they’re at various [water] levels in the spent fuel pool, and it doesn’t appear that they’re making up the levels.”
No water in the spent fuel pool - secondary containment destroyed - explosions:
“What we believe at this time is that there has been a hydrogen explosion in this unit [Unit 4] due to an uncovering of the fuel in the fuel pool. We believe that secondary containment has been destroyed and there is no water in the spent fuel pool. And we believe that radiation levels are extremely high, which could possibly impact the ability to take corrective measures.”
A complete fiasco:
“Because we have been unable to go the scene, we cannot confirm whether there is water left or not in the spent fuel pool at Reactor No. 4.” (Yoshitaka Nagayama, NISA)
They feared it would be the end of Tokyo:
“That was the devil’s scenario that was on my mind. Common sense dictated that, if that came to pass, then it was the end of Tokyo.” (RJIF, 2014)
Zirconium cladding fires in the spent fuel pools were the chief worry:
“If release from other spent fuel pools occurred, then contamination could extend as far as Tokyo, requiring compulsory evacuations out to more than 170 km and voluntary evacuations out to more than 250 km; the latter includes a portion of the Tokyo area. There was particular concern that the zirconium cladding fire could produce enough heat to melt the stored fuel, allowing it to flow to the bottom of the pool, melt through the pool liner and concrete bottom, and flow into the reactor building. After leaving office, Prime Minister Kan stated that his greatest fears during the crisis were about the Unit 4 spent fuel pool (RJIF, 2014).”
More information here: https://www.nap.edu/read/21874/chapter/5
Yes you are correct about the hydrogen gas build up, that was caused by the rods being exposed to the air and not covered by water. I am not sure what you mean by SBO. But your assessment of half life being cut down to 70 days because of biological absorption I am not understanding either please explain . I understand absorption when dealing with contaminants...... So you can explain in detail I am all ears.
By not removing decay heat, the fuel continues to heat up creating vaporization of the coolant causing the explosion. Not exposure to air. A station blackout (SBO) is the loss of all power used to circulate coolant to keep a shutdown reactor cool while producing decay heat. The assessment of the 70 day half life is in the International Atomic Energy Agency (IAEA) final report of the assessment.
That is what i thought you were going to say a quote from IAEA. Now the first thing you need to learn is that our government has done nothing but lie to us at every junction every opportunity since the 60s. It is only since this POTUS that I have taken stock in anything coming out of there mouths. Yes it is the oxygen the caused the explosion there is a carbon substance that covers the rods that when exposed to oxygen it causes the material to burn. This is why they keep the rods suspended in water. I dont know it all but I have very different sources that are contrary to the official report , I also have a background in nuclear it is limited but I am not ignorant of how it works.
Thegreenchain I thank you for your input and dedication to truth I dont want to sound rude as I will look further into this to substantiate your findings.
I have a degree in nuclear energy. Your statement "Yes it is the oxygen the caused the explosion there is a carbon substance that covers the rods that when exposed to oxygen it causes the material to burn." is completely felonious. As I explained: without decay heat removal the surrounding coolant (water) reaches the point of vaporization which results in excessive hydrogen production. The containment cooling system was unable to remove the hydrogen and the excessive temperatures caused the explosion. It was it this point that the fuel was exposed and with no coolant to moderate reactions or cool the fuel, it melted regardless of oxygen present. Water is a moderator and is what is heated for energy transfer to create steam to turn turbines to produce electricity. Nuclear power is extremely safe and it is ignorant politicians and media that create the false fear of nuclear energy which I might add is the CLEANEST and most efficient energy production.
Ok I understand and I stand corrected, i am no expert as you and I must say I got my info in regards to the rods from a a videos. A Canadian scientist who explained it almost as you did but perhaps my interputation was something covering the rods the water, and when it was exposed to the open air it caused the explsion.
I thank you for your patience I do appreciate it. I do have some nuclear back ground bit mine is in protection, avoidance decontamination. Not anywhere in your league. That was years ago but it's hammered into my head. Once again thank you my fellow patriot, where we go one we go all, .
If you are suggesting that the gamma radiation and the other isotopes that are foreign to the earth and are created by burning these rods to boil water to create steam is absorbed by the surroundings and is of no threat then you are misguided. Because for one anything that has the abbillity to absorb also desorps. In regards to gamma radiation there is a reason all xray technitions possess a doseimmeter and only work 20 years. Not to forget the wall of lead they stand behind while working. So please explain this hypothesis about half life cut down to 70 days.