Nuclear-Weapons Material From WW2 Found in Garbage Dump

One of the most dangerous substances known to man was found in an unlikely place: a garbage dump.

Workers cleaning up the Hanford Site, a huge Department of Energy cleanup site in southeastern Washington state, came across an old safe buried in a pit.

Cracking it open, they found a glass bottle — which turned out to contain plutonium made for the Manhattan Project in 1945.

Plutonium is extremely radioactive, and even a tiny amount could cause lung cancer in a human who breathed it in. But this wasn't just any plutonium — this was an extremely pure sample of the fissile isotope plutonium-239, used to make atomic bombs such as the one dropped on Nagasaki.

In fact, except for a tiny sample stored at the Smithsonian Institution, the 400 milliliters from the bottle is the oldest batch of plutonium-239 in existence. It's not enough to make a nuclear weapon, but it'd be plenty for terrorist to manufacture a "dirty bomb" with.

All the other sizable samples of plutonium-239 from 1945 went into the Nagasaki bomb or the Trinity nuclear-test bomb that preceded it. It's not clear why this batch was left out — or how it came to end up in a sealed safe abandoned in a landfill on the Hanford site.

A representative for the Department of Energy said that, contrary to an earlier report, the nuclear material was always well guarded. "The entire Hanford Site is a secure facility. There was no time where this material was 'unguarded' because the entire Hanford cleanup site is guarded by a highly-trained, armed, paramilitary force," the spokesman said.

The story was first detailed in the scientific journal Analytical Chemistry.

• Click here for a gallery of images from the cleanup site in New Scientist.

• Click here to read more about this in New Scientist.

• Click here for a similar report in Nature.

• Click here to visit's Natural Science Center.