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Radioactive water at Fukushima Daiichi: What should be done? (2018)

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Re: Radioactive water at Fukushima Daiichi: What should be done? (2018)

#11

Post by gnode »

warmwaffles wrote: post #8

Quick question / thought, why not run it through beds of sand that take some of the radiation and bury that sand somewhere? Eventually as you run the water through the sand long enough it should become less and less irradiated right?

The problem is that you have a large volume of radioactive fluid. The radioactivity is "low-level" but still poses a danger to health and life. If you store it somewhere, you have to be sure it will stay there. Additionally, if it turns out you stored it somewhere silly, you'd want to be able to get it back.

The alternative is to dilute it down so that it's less harmful, but then you have a larger volume, and so containing it is a larger problem. If you dilute it to the point that its volume is the entirety of water on earth, then it's at a safe level (and a fraction of the natural level), and so isn't a containment problem anymore.

Sand will not help the problem; the radioactive component is tritium, which is in the water molecules themselves. The sand will just mix with the water and give you a larger volume that has handling challenges of wet sand and evaporates and sweats radioactive water.

Re: Radioactive water at Fukushima Daiichi: What should be done? (2018)

#12

Post by imchillyb »

adrianN wrote: post #4

So oil tankers can apparently carry some 300000 tons. Three or four oil tankers full would then be enough storage space for the onsite water. Couldn't we fill some tankers and have them release the water far away from any fishing grounds?

> ...Couldn't we fill some tankers and have them release the water... @adrianN

1st) Who is this /we/ you speak of?

2nd) Who's tankers are you suggesting /we/ utilize?

3rd) Who is the governing authority here that is in charge of the WE, the VESSELS, and the area of release?

Who's backyard does this take place in?

How much compensation is being offered for these privately owned tankers that will be permanently damaged by the radioactive waste being carried?

Who is paying the wage and medical bills for the crews that are crewing said vessels?

Where does this labor come from in the first place?

Who is safety training these laborers in the proper use of protective gear, proper disposal procedures for contaminated gear, etc...

Finally, where the hell is this highly-contaminated water going to be released and or stored?

Most importantly, who the hell is going to pay for all of what you've suggested?

_____

I sure as hell am not going to pay for it. TEPCO sure as hell isn't going to pay for it. Japan sure as hell isn't going to pay for it.

SO, I ask again, who's footing the bill for this immensely complex and expensive process?

Re: Radioactive water at Fukushima Daiichi: What should be done? (2018)

#13

Post by jtms »

warmwaffles wrote: post #8

Quick question / thought, why not run it through beds of sand that take some of the radiation and bury that sand somewhere? Eventually as you run the water through the sand long enough it should become less and less irradiated right?

I’m guessing if there were a way to filter out the tritium they probably already would have. The article states that they already removed other isotopes from the water, but not the tritium. This leads me to believe there is something particularly tricky about separating it from water. Hopefully someone with some knowledge can weigh in here as I am curious as well.

Re: Radioactive water at Fukushima Daiichi: What should be done? (2018)

#14

Post by adrianN »

bitL wrote: post #10
adrianN wrote: post #4

So oil tankers can apparently carry some 300000 tons. Three or four oil tankers full would then be enough storage space for the onsite water. Couldn't we fill some tankers and have them release the water far away from any fishing grounds?

...and damage some preserved ecosystem in the process. Great idea!

The article made it sound like the water is mostly harmless and Sellafield dumps orders of magnitude more into the sea without dramatic effects.

Re: Radioactive water at Fukushima Daiichi: What should be done? (2018)

#15

Post by opwieurposiu »

Anyone who lives in Colorado receives a dose of many Fukushima's a year. I have a radon counter in my basement and watch the count ebb and flow with the seasons.

One self luminous exit sign contains about 0.00074 PBq of tritium. The Fukushima stored water contains about 0.76 PBq of tritium, enough for about 1027 signs. I suspect there is far more tritium in the exit signs in Tokyo then there is in the Fukushima water.

https://www.everglow.us/pdf/tritium-exit-sign-fact-sheet-lan...

Re: Radioactive water at Fukushima Daiichi: What should be done? (2018)

#17

Post by gnode »

bitL wrote: post #10
adrianN wrote: post #4

So oil tankers can apparently carry some 300000 tons. Three or four oil tankers full would then be enough storage space for the onsite water. Couldn't we fill some tankers and have them release the water far away from any fishing grounds?

...and damage some preserved ecosystem in the process. Great idea!

The same release from a vessel in open water is less likely to damage an ecosystem than release from the shoreline. That said, if it's diluted enough and released over a long enough period of time, it's unlikely to make much difference.

Re: Radioactive water at Fukushima Daiichi: What should be done? (2018)

#18

Post by Robotbeat »

Shorel wrote: post #16

So, this means I can eat fish caught in the Pacific ocean again? Is the radioactivity low enough?

It has been low enough the whole time.

Radioactivity is super easy to detect even at harmless levels. Sunburn is a far (probably a million times? More?) bigger concern with similar effects (radiation burns possibly leading to cancer), yet people still go outside.

Re: Radioactive water at Fukushima Daiichi: What should be done? (2018)

#19

Post by gnode »

jtms wrote: post #13
warmwaffles wrote: post #8

Quick question / thought, why not run it through beds of sand that take some of the radiation and bury that sand somewhere? Eventually as you run the water through the sand long enough it should become less and less irradiated right?

I’m guessing if there were a way to filter out the tritium they probably already would have. The article states that they already removed other isotopes from the water, but not the tritium. This leads me to believe there is something particularly tricky about separating it from water. Hopefully someone with some knowledge can weigh in here as I am curious as well.

Tritium can be refined, and is done for various applications (radiolabelling; nuclear weapons; nuclear fusion). However it's expensive, as is reflected by its cost of about $30k per gram. It'd be even more expensive to refine from a dilute solution.

That said, an imperfect distillation may be cheaper, but the quantities of fluid here are still huge.

Re: Radioactive water at Fukushima Daiichi: What should be done? (2018)

#20

Post by Robotbeat »

jtms wrote: post #13
warmwaffles wrote: post #8

Quick question / thought, why not run it through beds of sand that take some of the radiation and bury that sand somewhere? Eventually as you run the water through the sand long enough it should become less and less irradiated right?

I’m guessing if there were a way to filter out the tritium they probably already would have. The article states that they already removed other isotopes from the water, but not the tritium. This leads me to believe there is something particularly tricky about separating it from water. Hopefully someone with some knowledge can weigh in here as I am curious as well.

Tritium natural decays pretty quickly. Half life of 12 years.
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