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First contact made with melted nuclear fuel at Fukushima plant

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Re: First contact made with melted nuclear fuel at Fukushima plant

#41

Post by mikro2nd »

acidburnNSA wrote: post #21
mimixco wrote: post #15

It took 10 years to even get a robot that could get close to the fuel... and people still ask if nuclear might not be as bad as coal! The truth is that accidents like this can never be cleaned up or salvaged. It's time to move away from nuclear, as other countries have already figured out. Fortunately for us in the US, the last nuclear plant under construction today will likely be cancelled, as the last two were. The…

If you look objectively at the numbers, you'll see that nuclear is one of the safest forms of energy production we know. Even considering conservative estimates from Fukushima and Chernobyl, nuclear power has net saved over 2 million lives simply by displacing air-pollution related deaths that would have occurred had the nukes not been built. Coal kills on the order of hundreds of thousands of people per year. Fukush…

I don't know how nuclear can be considered remotely "carbon free" if you take into account the usually-externalised emissions incurred in mining, refining and processing the uranium ores into fuels.

Then, too, I've seen no figures on the carbon costs of nuclear waste-management.

Re: First contact made with melted nuclear fuel at Fukushima plant

#42

Post by moate »

aurailious wrote: post #25
toomuchtodo wrote: post #24

Earlier quoted context omitted.

Solar, wind, storage. Fusion at a distance. EDIT: "20 years from now" is still faster than any nuclear generator getting built.

So a mixture of unreliable, expensive, and "20 years from now".

Don't forget the chemical byproducts of producing solar and storage.

All options are trade offs, and I don't understand why "perfect" keeps preventing us from just getting "better".

Re: First contact made with melted nuclear fuel at Fukushima plant

#43

Post by hanniabu »

aurailious wrote: post #25
toomuchtodo wrote: post #24

Earlier quoted context omitted.

Solar, wind, storage. Fusion at a distance. EDIT: "20 years from now" is still faster than any nuclear generator getting built.

So a mixture of unreliable, expensive, and "20 years from now".

With many recent breakthroughs, fusion is now seen as very viable and just needs funding to finish it off. The last of the hard problems are solved and they just need to pull it all together and "adjust for rounding errors", so to speak.

Re: First contact made with melted nuclear fuel at Fukushima plant

#44

Post by x3n0ph3n3 »

JosephRedfern wrote: post #23

Forgive the macabre question, but if a human (or other living creatue) were to venture in to the plant and collect this fuel by hand, how long would they survive? I'm in no way suggesting that this is an option, of course -- just curious.

This might interest you and give you a benchmark for the lethality of approaching it: https://rarehistoricalphotos.com/the-elephant-foot-of-the-ch...

> After just 30 seconds of exposure, dizziness and fatigue will find you a week later. Two minutes of exposure and the body cells will soon begin to hemorrhage; four minutes: vomiting, diarrhea, and fever. At 300 seconds you have two days to live.

> All of the fire fighters and people who worked in building the sarcophagus died around a year or so after the event.

Re: First contact made with melted nuclear fuel at Fukushima plant

#45

Post by petschge »

ChuckMcM wrote: post #17

While I realize it was likely impractical to meltdown reactors just to develop the technology to clean them up, I find the process here pretty interesting. A lot of good engineering has gone into the effort, and the engineering challenges (and risks) of post runaway reactors has gotten a lot more data. The Chernobyl folks just entombed everything, which is a one approach, even though they can "walk up to"[1] the rema…

Boron actually mostly acts as a neutron poison, i.e. it absorbs neutrons. That way further (stimulated) decay of other nucleii that were hit by a neutron is eliminated and the chain reaction stops, reducing the production of thermal energy.

A moderator on the other hand inelastically scatters neutrons, converting some of the kinetic energy of the neutrons to heat and leaving a slower neutron. Moderators are used in reactors to bring neutrons down from their initial velocity to velocities where they are more likely to stimulate fission in another nucleus.

Re: First contact made with melted nuclear fuel at Fukushima plant

#46

Post by pvaldes »

ChuckMcM wrote: post #17

While I realize it was likely impractical to meltdown reactors just to develop the technology to clean them up, I find the process here pretty interesting. A lot of good engineering has gone into the effort, and the engineering challenges (and risks) of post runaway reactors has gotten a lot more data. The Chernobyl folks just entombed everything, which is a one approach, even though they can "walk up to"[1] the rema…

> the "China Syndrome" speculation is pretty much completely debunked

You would be dissapointed. Cou-cou! surprise! The ocean strikes back!.

Unexpected source of Fukushima-derived radiocesium to the coastal ocean of Japan. 2017. Sanial, Buessler, Charette, and Nagao. PNAS. DOI:10.1073/pnas.1708659114

"Sanial, Buessler, Charette and Nagao, scientists from Massachusetts and Japan found a new source of Caesium-137 to the environment after the Fukushima accident. From 2013 – 2016 they visited 8 different beaches within 100 km of the accident site, took sand and water samples and measured its radioactivity.

They found that at the bottom of their sand samples, up to 2 m deep into the beach, the 137Cs concentrations were incredibly high, up to 480,000 Bq per square meter in their deepest samples. The soil in the restricted zone of the Fukushima site, up to 100 km away, measured ~100,000 Bq per square meter.

This means even tens of kilometers away, the radiation can actually be higher than near the disaster. (Because, huh?, 137Cs sticks to the sand grains).

https://oceanbites.org/going-nuclear-radioisotopes-from-fuku...

Re: First contact made with melted nuclear fuel at Fukushima plant

#47

Post by jade12 »

mimixco wrote: post #15

It took 10 years to even get a robot that could get close to the fuel... and people still ask if nuclear might not be as bad as coal! The truth is that accidents like this can never be cleaned up or salvaged. It's time to move away from nuclear, as other countries have already figured out. Fortunately for us in the US, the last nuclear plant under construction today will likely be cancelled, as the last two were. The…

Lest anyone forget, the Centralia (coal) mine fire has been burning since at least 1962 and no one knows how to stop it. The Fukushima Daiichi incident really doesn't seem that bad to me, comparatively speaking.

https://en.wikipedia.org/wiki/Centralia_mine_fire

Re: First contact made with melted nuclear fuel at Fukushima plant

#48

Post by lotu »

mimixco wrote: post #15

It took 10 years to even get a robot that could get close to the fuel... and people still ask if nuclear might not be as bad as coal! The truth is that accidents like this can never be cleaned up or salvaged. It's time to move away from nuclear, as other countries have already figured out. Fortunately for us in the US, the last nuclear plant under construction today will likely be cancelled, as the last two were. The…

Nuclear kills less people than Coal mostly from asthma, but coal even causes more cancer because on a normal day it emits far more radiation in the form of small particles of radioactive dust present in coal.

The real danger of Nuclear is it can make land unusable by people for centuries (this actually appears to be good from a biodiversity and ecological heath stand point because people do more damage to that than some radiation). But by contributing to climate change coal has the potential to put far more land under water.

If we had gone for widespread adoption of nuclear power on the scale of Japan climate change would not be a problem like it is today.

Re: First contact made with melted nuclear fuel at Fukushima plant

#49

Post by acidburnNSA »

simmanian wrote: post #16

Has there been a proper study done on how dangerous it is to live in areas around the plant, or how safe it is to eat produce grown from Fukushima and all the fish caught in the area? There's been so much rumor and fake news around this topic that I don't know what to think.

Absolutely yes. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) does reports every year or so on the status. Here's the 2017 one [1].

[1] http://www.unscear.org/docs/publications/2017/UNSCEAR_WP_201...

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