The Chernobyl nuclear disaster is the worst power plant disaster in history.
Just 2 months after the disaster, roughly 600,000 Soviet cleanup workers were given the deadly task of covering the plant's exposed reactor with a massive 'sarcophagus' encasing.
Now, it has emerged that, 33 years later, the sarcophagus has to be dismantled before it collapses. Thankfully, this was known ahead of time and an impressive undertaking in precise engineering is making sure that the existing structure is safely replaced.
Replacing the 'sarcophagus'
The 'sarcophagus' encasing the contaminated site of Chernobyl reactor 4 was made in order to lock in radioactive materials like corium, uranium, and plutonium. It was erected only two months after the disaster occurred on April 26, 1986.
At least 31 of the workers who constructed the encasing died of acute radiation sickness.
The danger of the construction zone is partially responsible for the deterioration happening today. Though the covering was made from 400,00 cubic meters of concrete and approximately 16 million pounds of steel, the conditions meant that it was hastily built, leaving the building's joints unsealed, and openings in the ceiling, as Science Alert reports.
Now, 33 years later, the covering has to be replaced: SSE Chernobyl NPP, the company that manages the nuclear plant site, has released a statement online saying the probability the structure will collapse is "very high" if it is left in its current state.
All of this is part of a planned disassembly of the original encasing - in fact, SSE Chernobyl NPP's statement outlines the US$78 million construction contract focused on methodically taking it apart.
The statement says:
"The removal of every element will increase the risk of Shelter collapse that in turn will cause the release of large amounts of radioactive materials inside the inner space of New Safe Confinement arch."
The New Safe Confinement (NSC) is bigger than London's Wembley football stadium and taller than the Statue of Liberty — it was installed in 2016 and will keep the site safe for another 100 years. It will also allow for the safe disassembly of the original 'sarcophagus.'
As the statement says, "the disassembled elements will be remotely conditioned in the NSC Technological Building where they are to be cut, decontaminated, put into shipping casks and prepared for transportation to processing or disposal."
Robotic cranes and arms will be used to move the most contaminated objects and materials. Cleaning operations for Chernobyl are expected to last until 2065.