Tjernobyls kamp mot klockan – i 100 år till
Publicerad 15.25
Chernobyl's race against time – for another 100 years
TT
Published 15.25
Staff descend to inspect the damage to the "New Shelter" after the drone attack last year. Picture taken on February 14, 2025.
1 / 6Photo: Efrem Lukatsky/AP/TT
Forty years have passed since the fateful night when reactor 4 in Chernobyl exploded. But the cleanup work has barely begun. And a Russian drone attack last year is making the race against time much worse.
- The inner "sarcophagus" is in danger of collapsing. That must not happen, says expert Shaun Burnie on the phone from Kiev.
01.23 has gone down in atomic history. It was then, in the early spring morning of April 26, 1986, that something went wrong in Chernobyl, about ten miles north of the Ukrainian capital Kiev.
Several safety systems in the nuclear power plant were shut down for testing, so a minor incident in reactor 4 quickly became a major one. An explosion was so powerful that the 1,000-ton reactor lid, known as “Elena”, flew off. This allowed flames and smoke to freely spread radioactive material into the sky, and out over Europe.
Forty years later, “Elena” still stands on the stilts next to the reactor. The radiation hazards have been, and are, so great that the area has only been covered with so-called sarcophagi – the first one that was built, more or less in a panic, back in 1986, and an outer vault built in the 2010s.
“More than a machine”
The newer containment is internationally known as the NSC (New Safe Confinement), and was built as a kind of gigantic workshop hangar over the first one, which was leaking from the start and needed constant monitoring.
– The NSC is more of a machine than a building. A machine that cost 2 billion euros, Shaun Burnie tells TT.
Among other things, the NSC has cranes, struts and beams that act as the unstable sarcophagus' "braces".
Shaun Burnie has 40 years of experience as a nuclear energy expert, and has also worked on the aftermath of the Fukushima disaster in Japan. He is now stationed in Ukraine on behalf of the environmental organization Greenpeace.
Radioactive debris
He has been inside the NSC several times. People are allowed to be there under strictly controlled conditions.
- Inside the reactor there is of course a lot of nuclear fuel, nuclear material, radioactive debris, concrete, steel, graphite from the reactor core ..., he describes the view.
The situation has been radically worsened by the incident that occurred one early February morning last year. During Russia's attack in the area, an Iranian Shahed war drone hit the roof of the NSC.
– There was a powerful explosion, which pierced the outer shell and also pushed through the inner shell, says Burnie.
Russia has never explained the incident, but Burnie has no doubt that it was a deliberate attack.
– The drone flew very low, below the radar. Afterwards, we could see the parts lying in the snow.
“No control”
The explosion opened a 15 square meter hole. Fires broke out, and could only be completely extinguished after three weeks.
The radiation and the ongoing war have meant that the damage could only be repaired very provisionally. So at present, the “sarcophagus” is threatening to collapse, and the structure that was supposed to save it, the NSC, is patched and repaired as best as possible.
– The firefighters had to open 300 holes, so now they have no control over the humidity. The question then becomes, how long can this structure function?
The NSC was designed to last for 100 years. It was built with air conditioning, because the hundreds of thousands of metal parts inside cannot be protected from rust and maintained in the normal way. But after the attack, weather, wind, water and snow eat into it.
Risk of reaction
No one knows exactly how it will affect the hazardous substances inside, which include volatile radioactive dust and uranium pellets – barely larger than a fingernail, but each potentially deadly.
In connection with the 40th anniversary of the accident, Greenpeace has hired one of the NSC's designers, the American Eric Schmieman, for a status report. He writes that it is not possible to rule out the risk of an "accidental nuclear chain reaction".
- The concern is mostly based on water getting into the sarcophagus, into the reactor, says Burnie.
That concern has been there all along, and the situation has been monitored via neutron meters for some time. But the situation has now worsened and become more difficult to understand when the NSC is broken.
– They have plugged the big hole, and will continue with repairs for the next 12 to 18 months.
Only two shifts
The work not only costs a lot of money, but staff is also increasingly scarce. For employees in the nuclear industry, there are higher limits for radiation doses than for the rest of us, but Burnie says that in Chernobyl it can still be extremely fast to reach a yearly dose.
– There are very large variations even within the NSC, but in some places you may only be able to work for twelve hours. So you go in and work maybe two shifts, then it's a stop.
Chernobyl is only 15 kilometers from the border with Belarus, which Russian attacks often go through.
– Not every night, but at least every second, every third night, Russian drones, Russian robots fly over Chernobyl, says Burnie.
– How many foreign engineers, contractors, welders will be allowed to come and work, he wonders.
“Getting things done”
The work must continue for many years to come. According to previous plans, the actual fuel from reactor 4 can only begin to be removed around 2050, a laborious operation that could last until the early 2100s, writes Eric Schmieman. Now, further question marks have been added with the drone attack, but there is not much room for further delays. “The 100-year lifespan of the NSC is calculated from commissioning in 2019, and thus runs until 2119,” the report states.
The cleanup work is therefore a race against time that will last more than a century, most of which remains to be done. Shaun Burnie nevertheless sounds cautiously hopeful.
– One thing that has really struck me after years of working in Ukraine is that it is a country where you get things done. They do amazing things here, incredible things.
But, he adds:
– This is an enormous challenge.
FACTS
The Chernobyl accident
On the night of April 26, 1986, reactor 4 at the Chernobyl nuclear power plant exploded, about ten miles north of the Ukrainian capital Kiev.
The cause was a minor incident, which could grow because safety systems had been turned off to carry out tests.
Explosions and fires destroyed the roof, and large amounts of radioactive particles were released into the atmosphere, then falling all over Europe.
Outside the then Soviet Union, the first signal of the disaster came at the Forsmark nuclear power plant outside Gävle, where the fallout triggered a radiation alarm two days later.
The radiation also meant that the cleanup work had to be done extremely carefully, and is set up as a plan that will last almost 150 years. The nuclear fuel is expected to be removed in the second half of this century, and the cleanup work will clearly not begin until the 2110s.
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