Fukushima meltdown hastens decline of nuclear power

Post by **clv101** » 21 Aug 2013, 11:49

Well, the one hundred millisieverts dose is equivalent to the 5 year nuclear worker limit (apparently). This water is delivering that dose in 1 hour (standing 50cm away). So yes, sloppy wording to include "per hour" where he did, I expect his English isn't perfect, but it's clear what he meant.

Receiving 400 mSv in a short period of time is enough to cause symptoms of radiation poising and 2000 mSv can be fatal.

If there really are puddles of stuff on the ground, delivering 100 mSv per hour doses to folk in the immediate area, working in that environment for a few days is likely to be fatal.

How are they finding enough workers to rotate them rapidly enough not to kill them - remembering there haven't been any reported deaths related to radiation poising (yet).

UndercoverElephant · Post by **UndercoverElephant** » 21 Aug 2013, 13:38

Looks pretty bad to me.

biffvernon · Post by **biffvernon** » 21 Aug 2013, 20:09

Highly radioactive water was found to be leaking from a storage tank into the ground at the plant on Monday.

I'm not sure there are actual puddles on the ground within sight of workers, rather the water is leaking into the ground, from where it can seep into the ocean and head for California or wherever.

It might be entertaining to trawl back through the comments made two years ago and see who was poo-pooing suggestions that this event was serious. Or even page 1 of this thread from May 2012. I don't think I've changed my position in the last 15 months.

Little John · Post by **Little John** » 21 Aug 2013, 20:49

biffvernon wrote:
Highly radioactive water was found to be leaking from a storage tank into the ground at the plant on Monday.
I'm not sure there are actual puddles on the ground within sight of workers, rather the water is leaking into the ground, from where it can seep into the ocean and head for California or wherever.

It might be entertaining to trawl back through the comments made two years ago and see who was poo-pooing suggestions that this event was serious. Or even page 1 of this thread from May 2012. I don't think I've changed my position in the last 15 months.

What is the source of radiation emanating from the contaminated water?

woodburner · Post by **woodburner** » 21 Aug 2013, 20:53

The water is pumped around the control rods to cool them.

Little John · Post by **Little John** » 21 Aug 2013, 20:57

woodburner wrote:The water is pumped around the control rods to cool them.

That doesn't make the water itself emanate radiation does it? Radiation emanates from radioactive material. Water is not radioactive. Water that is contaminated with radioactive material emanates radiation, But that is coming from the contaminant, not the water that is carrying it.

What is the contaminant?

Unless my understanding of the physics is wrong, which it might be.

Little John · Post by **Little John** » 21 Aug 2013, 21:15

Okay, I've just had a read up on water and radioactivity and it appears my initial assumption was right, water is not radioactive nor can it be made to be due to it's density and overall chemistry. It is precisely for this reason that it is used as the favoured coolant at nuclear power stations because it is such an effective radiation insulator.

Therefore, all radiation that is emitted from water is actually coming from the contaminants it is carrying. Indeed, it is common practice for nuclear power plants to routinely mechanically filter the coolant water to clear out such containments. Such filtering leaves the water completely non-radioactive. In fact, I have read that, at a pinch, one method of cleaning the water is simply to leave it in shallow ponds to evaporate off. The evaporated water will be radiation free because all of the radioactive material will end up as as the debris that is left behind after all water has evaporated off.

So, why the hell don't they simply do that with it?

woodburner · Post by **woodburner** » 21 Aug 2013, 21:28

Your attitude is unhelpful and disrespectful. Do you not think the people dealing with the situation will be thinking of how to solve the problems? Look at the pictures of the site.It is a mess. I suspect most of the infrastructure is damaged. It is worth remembering people working on site will be exposed to possibly lethal doses of radiation. I wouldn't want to do it,would you?

The water is stored in tanks, one of which leaked. Possibly there is more than one leaking. Water flowing through the site, normal ground water flow, will also be picking up contaminates.

PS I never suggested the water was radioactive, I said it was used to cool control rods which are probably damaged, and disintegrating, however small the rate.

Little John · Post by **Little John** » 21 Aug 2013, 21:29

In any event, given that the water itself is not radioactive and give that the water can be cleaned, either via mechanical filtering or via evaporation/distillation, the pertinent question is what is the source material of the radiation? The reason i ask is because this will tell us whether it is gamma rays or beta/alpha particles. It will also tell us the half lives involved. It matter to know these things because not all radiation is the same and some has far more long reaching consequences than others. To simply say that it is "radioactive" does not tell us enough to know how dangerous it actually is for the wider world outside of the Fukishima plant.

Little John · Post by **Little John** » 21 Aug 2013, 21:31

woodburner wrote:Your attitude is unhelpful and disrespectful. Do you not think the people dealing with the situation will be thinking of how to solve the problems? Look at the pictures of the site.It is a mess. I suspect most of the infrastructure is damaged. It is worth remembering people working on site will be exposed to possibly lethal doses of radiation. I wouldn't want to do it,would you?

The water is stored in tanks, one of which leaked. Possibly there is more than one leaking. Water flowing through the site, normal ground water flow, will also be picking up contaminates.

What are you on about you blithering idiot?

"Attitude"? "Unhelpful"? "Disrespectful"?

Grow the F--k up

woodburner · Post by **woodburner** » 21 Aug 2013, 21:36

You are also under the influence (again). I will accept your apology (again) when you are sober tomorrow.

The contaminate appears to be Strontium-90 also Tritium both at "elevated" levels.

http://www.bbc.co.uk/news/world-asia-22964089

Little John · Post by **Little John** » 21 Aug 2013, 21:37

woodburner wrote:You are also under the influence (again). I will accept your apology (again) when you are sober tomorrow.

I'm completely sober mate. You need to get a bloody grip.

woodburner · Post by **woodburner** » 21 Aug 2013, 21:41

I might feel insulted if was not for the fact you often treat people on PS this way.

biffvernon · Post by **biffvernon** » 21 Aug 2013, 21:43

I think W was suggesting that the people working at Fukushima have the very best nuclear engineering advice in the world available to them and are probably doing about the best job possible.

To be pedantic, water can be radioactive if the hydrogen is replaced with deuterium or tritium but this is unlikely to be significant in this case. The main contaminant of concern is caesium and there is also a cocktail of other radio-nucleotides that are being washed out of what were once upon a time three nuclear reactors but are now three mangled heaps that the need to be kept cool by washing tons of water over them.

Filtering and evaporating don't seem to be possible at the order of magnitude required, so they have a problem.

Edit: seems there's quite a bit of tritium, but it has a short half-life so is not as important as the caesium, strontium et al.

woodburner · Post by **woodburner** » 21 Aug 2013, 21:47

Strontium-90

Natural strontium is nonradioactive and nontoxic, but 90Sr is a radioactivity hazard. 90Sr undergoes β− decay with a half-life of 28.79 years and a decay energy of 0.546 MeV distributed to an electron, an anti-neutrino, and the yttrium isotope 90Y, which in turn undergoes β− decay with half-life of 64 hours and decay energy 2.28 MeV distributed to an electron, an anti-neutrino, and 90Zr (zirconium), which is stable.[3] Note that 90Sr/Y is almost a perfectly pure beta particle source; the gamma photon emission from the decay of 90Y is so infrequent that it can normally be ignored.