It’s been six-and-a-half years since Fukushima Dai-ichi was hit by an earthquake and tsunami.
And now, nuclear plant radiation has showed up somewhere scientists didn’t expect -- the
beach.
A nuclear plant like Fukushima has nuclear fuel rods inside of a water bath.
The bath helps regulate their temperature, because nuclear rods heat up due to radioactive
decay.
They’re hot all the time, even when they're not part of fission.
When Fukushima’s plant was hit by a tsunami, the systems that kept the water baths cool
stopped working, the rods overheated, and had a melt-down, literally.
To try and stop it, they ran seawater (the nearest cold thing) over the melting fuel
rods…
This made the water radioactive, as cesium-137 (a byproduct of the radioactive uranium) is
water soluble, but did help cool the rods.
Then they had to clean up the radioactivity.
Though radiation is invisible to us, it’s just really tiny particles that get caught
on dust, then on your clothes.
80 percent of the decontamination, specifically of people, after Fukushima can be simply: removing any clothing being worn
They also had to get the dust out of the environment.
In the case of Fukushima, 4 centimeters (1.6”) of topsoil was bagged up and hauled away.
That said, you have to know the radiation is there before you can clean it off.
A new study of the beaches around Fukushima found more radioactive Cesium-137 than expected.
Turns out they overlooked the beaches around the plant.
Radioactive particles are often called “sticky.”
they stick to surfaces, plants, clothes, soil.
And in this case, after the company ran seawater through the plant, and the tsunami receded, that seawater spread radiation
throughout the seafloor (and elsewhere), but scientists thought it would stay in the water
around the plant, in Fukushima harbor.
They were wrong.
Instead, it got into the sand, and re-leached into the sea and groundwater stretching for
miles.
In a new paper, the Woods Hole Oceanographic Institution and Kanazawa University hypothesize
the Cs-137 stuck to the sand, and is now slowly being washed away, spreading low levels of
radiation around the region.
Turns out, sand is like a big sponge, and the sticky particles get trapped inside.
Now that they know it’s there, they can start the cleanup.
Normally, radiation showers are literally just washing the radioactive dust off your
body.
Rain washes it out of the street and soil.
Over time, it ends up dispersed so much, that even if there are a few particles here and
there, it’s no longer dangerous.
It sucks, and you don’t want to think about it, but it won’t hurt you -- like birds
pooping in a water reservoir.
After a meltdown, people use the same tools as anywhere else to clean low-radiation areas.
Brooms, mops, brushes, shovels.
They wipe down surfaces… wash their hair… it’s funnily similar to other clean-up jobs,
except one pesky difference… any tools used are now considered radioactive and have to
be stored safely after the cleanup.
In this new paper they showed seawater makes the particles less sticky over time.
So, eventually, the beach will return to normal but for now they’re sort of stuck with it.
And it’s good that they know that it’s there.
It’s important to note, this is not enough radiation for the Japanese population to worry
about.
They’re very clear on that.
(And it’s definitely not an issue if you’re in the US or elsewhere -- we have a video
about it).
Instead, this new research is highlighting the beach problem so future nuclear plant
designers can realize just how far-reaching any possible pollution can be.
The moment people say “radiation” a lot of people flip out.
But unless you’re living near the Fukushima plant: you’ll be fine.
Worry about radiation from the sun, that’s more pressing.
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We’ve also got a video here about Chernobyl.
That plant is still a disaster, so they’re building a giant shield over it.
Click to watch.
FYI As Fukushima cleanup continues, people have actually repopulated the city near the
plant.
They’re wary, but not wrecked.