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Fukushima Leak Traced To Overflow Tank Built On a Slope
AmiMoJo writes "The ongoing leak of radioactive wastewater at the Fukushima Daiichi nuclear plant has been traced to an overflow tank that was built on a slope. Because one side of the tank is lower than the other, water slops over the side when it is nearly full. TEPCO estimates that 430 litres of wastewater seeped outside the barrier around the tank and say some of this water may have flowed into the sea, about 200 meters away. They detected 200,000 becquerels per liter of beta ray-emitting radioactive substances in water pooled inside the barrier around the tank. The safety limit is 30 becquerels per liter. Officials say that a miscommunication with contractors led to the blunder."
No worries then
So they can't even manage a level holding tank and they are allowed to keep managing this clean up?
How is this level of incompetence possible?
Does Japan lack the technology to build level storage tanks? Or to inscribe a maximum fill line in the tank otherwise?
Oops...
430 liters.... LITERS. This is about two 50 gallon drums. The only reason this is making news is because TEPCO's overall problem with radioactive water gushing into the ocean is as catastrophic as BP's DW Horizon - possibly worse -- but they won't admit it.
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One side was built using cm and the other one using inches
They should have hired Hank Hill to put it in. The could have told him it was a septic tank. It would have been perfect and had a lawn over it.
It's called "OVERFLOW" tank, hello!
now fix it.
The Kruger Dunning explains most post on
Vanguely reminiscent of Titanic's "watertight" compartments, which were watertight at the SIDES, but open at the TOP. I believe it was "unsinkable" in some technical understanding of the word. That is, a localized hull breach that filled only one compartment would not have sunk the ship. But water could spill from one compartment to another when the ship was tilted, and thus the entry of water was not confined to the compartments where the leak was. Or something like that...
"How to Do Nothing," kids activities, back in print!
1. Flow rate of leak? If we're talking about something in the hundreds to thousands of liters...well, who cares if it hits the ocean? 200,000/30 is less than 7000. So the radioactive liquid just needs to be diluted by seawater to a ratio of 7000:1 (assuming negligible background radiation already in said seawater). That'll happen pretty quickly once it lands in the ocean (fact: The Pacific Ocean is really big). For a frame of reference, a mere olympic pool holds 2.5 million liters of water.
2. What is the beta emitter(s)? Short half life, long half life? If its I-131, just fix the leak and stay away for a few months. If its Sr-90 better stop it soon!
1) The current problems are just happening while the earth around is half way stable and not shaking too much. But what will happen if a half way decent earthquake is hitting the area of Fukushima? What will then happen to all those water tanks which seem already now to have bigger problems on a regular basis? What will happen to all the other sensitive parts of the nuclear plant whose structure is already badly damaged from the previous tsunami.
2) How many decades will the damaged poweplant still have to survive before it is not anymore a danger?
3) How frequently are half way decent earthquakes in that region?
I'm sure that the big catastrophy is still comming .. and will come sooner or later...
Vanguely reminiscent of Titanic's "watertight" compartments, which were watertight at the SIDES, but open at the TOP.
That is a reasonable design when you look at the tradeoffs. Titantic had 16 compartments, and could withstand up to four being breached at either the bow or stern, and even more could be breached amidship (where they would not cause much tilt). The problem is that five were breached, all at the bow. This was a "worst case" scenario. Even then, they may have been able to save the ship if they reacted quickly, by flooding the last compartment aft. That would have helped to balance the ship. But by the time the captain realized the full extent of the damage, the bow was sinking, the stern was rising, and it was too late.
Did the same people design this tank that couldn't handle the English-to-Metric conversion problem at NASA?
nice
Have you ever heard of "bio-accumulation"? It's a process where e.g. a growing child drinks so much milk or eats so much fish, that part of the resulting Calcium intake can be used to grow her skeleton. Like the bits around her bone marrow. Where the blood cells are made. For the rest of her life (well, there is probably some replacement; one Calcium atom is as good as any other).
If you look at the periodic table, Sr is one below Ca. Beta radiation may not be very penetrating outside your skin, but you wouldn't want the source to be inside your bones, irradiating your marrow.
To be, or not to be: isn't that quite logical, Slashdot Beta?
Meaning you more or less have to stand in the pool for them ebil radiations to get to you.
IIRC, there was a show I watched on the sinking that took the premise of counterflooding and tested it. They built a scale model, and they were able to fairly accurately recreate the actual sinking, without counterflooding. They then tested what would have happened if they had counterflooded the ship to maintain its trim. Counterintuitively, the ship actually sank faster with counterflooding. I think they explained it by showing that while the out of trim condition contributed to the "ice cube tray" phenomenon that finally sank the ship, the counterflooding would not stop that. It wouldn't even slow it down. With the flooding in the bow from the strike of the glacier, combined with the negative buoyancy of the counterflooded aft, the ship was so low in the water at that point, it allowed the compartments aft of the comprised compartments to fill the adjacent compartments even faster, while the ship was now that much closer to sinking due to the negative buoyancy of the counterflooded aft. They also explored the stability of the ship in such a condition. They found that the ship became unstable laterally, and thus it would have risked a capsize as well. Overall, it was better not to counterflood.
Brawndo: It's what plants crave!
More to the point: why were these tanks designed with open (or for all practical purposes open) tops?? If that minimum amount can slop out just due to grade, how much are they losing just to freaking evaporation?
-Boom!
Officials say that a miscommunication with contractors led to the blunder.
Like what? They have different definitions of "level" and "plumb?"
Because one side of the tank is lower than the other, water slops over the side when it is nearly full.
Why would anyone *want* build a containment tank like that? This could have been avoided if someone had simply said, "Are you sure? Because this is stupid." Also, the phrase "nearly full" would obviously mean something different on opposite sides of the tank - another clue that something was wrong...
It must have been something you assimilated. . . .
Contractors are a nifty feature of modern corporations. When shit hits the fan, the big firm can say it did nothing wrong, it was the contractor fault. On the other hand, the contractor does not care, PR is not its problem.
IMO the big firm should be fully liable, including in PR area. We should never hear about "the contractor fault". They chose to outsource, now if the work was badly done, it is their problem, they just have to sue the contractor for the loss.