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> “The Elephant’s Foot,” Is Still Lethal

Oh, I assumed that it'd be safe after a couple decades...

its actually emmiting radio active waves
Maybe a after a couple thousand decades :-)
Yea, the title doesn't reflect the scale of the consequences.
(2013)

Since this article was published, the “New Safe Confinement” has been completed: https://en.m.wikipedia.org/wiki/Chernobyl_New_Safe_Confineme...

Yes and the foot is still just as lethal inside it and will be for quite some time, your point is?

Great estimation here for how long and how much-

https://www.reddit.com/r/askscience/comments/8hp7l5/what_is_...

“The elephants will probably go away long before the radiation all goes away.”

>Yes and the foot is still just as lethal inside it and will be for quite some time, your point is?

Ummmmmmm, I’m confused now.

I noted the (2013) as there is a convention to append the year to the title for older articles. And reading the article, it talked about the New Safe Confinement as still being under construction, so I linked to the Wikipedia article showing that it had been completed.

Now this is a wild guess on my part, not being a nuclear engineer and all, but I reckon that the foot is probably not just as lethal now it is inside this 'New Safe Confinement' thingy, unless they have gone and named it really, really badly.
The elephant's foot is quite deep under the reactor in a lower level of the complex. So I don't think it specifically is any more or less safe since you have to go to a lot of effort to get near enough for it to hurt you.

The New Safe Confinement has a different purpose - to stop radioactive dust and debris from the reactor itself (a bit higher up) from spreading into the nearby area and being spread by the wind in case the hastily constructed original containment structure collapses (they are going to remove that old structure now the NSC is finished so that doesn't happen, I believe).

TFA does note:

> Born of human error, continually generating copious heat, the Elephant’s Foot is still melting into the base of the Chernobyl nuclear power plant. If it hits ground water, it could trigger another catastrophic explosion or leach radioactive material into the water nearby residents drink.

I had never heard that it was "still melting into the base of the Chernobyl nuclear power plant". Given that it's only 10% as radioactive as it was initially, that seems unlikely.

This article (from 2016, three years later than TFA) says it’s estimated to be ‘slightly higher than the ambient temperature’ - https://www.atlasobscura.com/articles/the-famous-photo-of-ch...

While it reaching groundwater was definitely a concern in the 80’s, I don’t think it’s actually moved significantly or is expected to in the future.

Thanks. That's more or less what I expected.

"China Syndrome" was an influential film. But until Fukushima, I don't believe that we saw melted core "lava" reach groundwater.

This matches my understanding. It's been a few years since I was into this stuff so bear with me.

The NSC is so we can dismantle the Sarcophagus (the old containment structure). The fear is a explosion caused by the collapsing Sarcophagus (or perhaps there is another structural concern) might let the Elephants Foot reach the waterbed underneath the empty man-made cooling reservoir.

Here is a cross-section[0] of reactor 4 that shows the Elephants Foot (corium) at the bottom. I wish it'd show how far deep until water. I can't find information as to whether water even exists, or if this was just speculation (but Pripyat is swampy/marshy).

[0] https://i.imgur.com/qozfDP1.png

Without guessing the mass cannot be "just as lethal" now as at any point in the past. Its lethality comes from decay of unstable isotopes. Radioactive decay has a half life so radiation inexorably falls with time and lethality necessarily falls with it.
That would be true if exactly one isotope decade into a stable isotope. With more complex decay chains etc that does not always apply.

Ex: A has a half life of 100 years and B has a half life of 10 years. If the sample starts at 100% A it will become more radioactive for the first few years until B reaches a steady state.

The radiation is a bad thing. And the radioactive isotopes in the thing are also bad. Considering it's from what I've heard and what I expect, turning slowly to dust, staying away from it is a good idea.
Very. Which is why the NSC was built to isolate it for at least 100 years (presumably it will be reinforced regularly by successive generations). Nothing we can do except allow it to decay to safe levels over time.
There's Nova documentary on Netflix about construction of NSC. Quite some amazing engineering.
It's featured in somewhat distorted shape in "Stalker: Shadow of Chernobyl" in one of the underground tunnels.

https://i.imgur.com/TVvbcan.jpg

Looks like that's just a generic solidified corium flow. Elephant's Foot just happens to be a famous solidified corium flow.
How many corium flows are there that there can be a generic one? Or a famous one?
I’m pretty sure the game has a version of the actual Elephant’s Foot, but this doesn’t look like it. At the end of the first game you go down into the remains of the Power Station to make a wish like the room in Tarkovsky's Movie. I’ll have a look for some gameplay videos.
> The Elephant’s Foot will be there for centuries

Does that mean it won't bleed into water supply before then?

The "foot" is composed of (now) solid material, and sitting on a concrete pad onto which the reactor building was constructed. Around the building is the "New Safe Confinement" structure.

So no, it will not bleed out.

Does the New Safe Confinement also extend into the ground?
It doesn't, but after the disaster, the basement areas were eventually filled with a lot more concrete. It's not just the very thick concrete pad between it and the groundwater, and it no longer generates enough heat to threaten to melt through.
Fukushima might provide some insight as to how likely it is a reactor would experience a "China Syndrome" where a meltdown occurs and forms a mass that is hot enough to break through the containment systems in place through to groundwater and etc.

Fukushima was not a modern reactor with fewer safeties than most modern systems and even there with an uncontrolled meltdown the "China Syndrome" did not occur. The fuel fused to the sand at the bottom and stopped.

I'm not an industry professional but I suspect Fukushima may indicate that the likelihood of a "China Syndrome" type event is less likely than was previously thought.

The title of this post needs a "(2013)" tag added. This is an older article, and is out of date.
That would be true if exactly one isotope decade into a stable isotope. With more complex decay chains etc that does not always apply. https://sushkom.com
I am surprised I can’t find more recent photos, I would have assumed robots would be regularly sent over the years to monitor it.
Nope.

1. the room with the elephant foot is hardly accessible now; 2. nothing interesting happens with it, no need to monitor

If you can, find the documentary BBC Horizon, Inside Chernobyl's Sarcophagus. I first saw this in the 90s as a kid and I was blown away. Absolutely crazy situation at the time. Hats off to the Liquidators and the scientists who tried to mitigate this mess. Many died and have been forgotten since.
It's only lethal if you attempt coitus or ingestion.
Before the dreaded HN grey curtain of we-dont-like-you descends on my post... while most of the article is well written, two helpings of TRIPE in this article jumped out at me. I'd expect better from a writer for Scientific American.

The first,"the Elephant’s Foot is still melting into the base of the Chernobyl nuclear power plant. If it hits ground water, it could trigger another catastrophic explosion or leach radioactive material into the water nearby residents drink."

This is ludicrous! The thing is only slightly temperature-hot. Was the writer reacting to that famous jiggly time lapse photo with the waving flashlight... that just HAPPENS to trigger everyone's molten China Syndrome fantasy? More about the photo, and apologies to anyone (like the article's silly author) who thought the photographer had died a horrible death whispering the word, "Rosebud".

https://www.quora.com/Is-the-elephants-foot-still-hot

The other piece of TRIPE is a dangerous general malaise of willful containment ignorance. Storing nuclear waste was never considered the best idea, not even in Fermi's day. It is the competent science writer's job to communicate that wringing our poor hands in despair and waiting oodle-thousands of years is not the only option.

It is safely contained within our own time frame, and IF we should desire to grind it up and render it with technology we NOW POSSESS with actual means just beyond the corner (bombarding it with fast neutrons, reaping heat energy in the process)to result in a short decay product that is a few hundred years from walk-away safe.

Now we cannot financially afford to do that on this day or the next, but that is no cause for a SCIENCE article to fail to remind us that its current dangerous state is from a lack of follow-through and not of possibility.

It's not enough to just present the truth about radiation and nuclear energy any more. Too much noise. We must push back at the ignorance and hysteria, make sure the young do not grow up steeped in superstition.