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by stephen_g 2479 days ago
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).
2 comments
smittywerben 2479 days ago
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

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mirimir 2479 days ago
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.

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stephen_g 2479 days ago
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.

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mirimir 2478 days ago
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.

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