By Audrey Carleton
Reports that Russian troops opened fire at Zaporizhzhia, the largest nuclear power station in Ukraine and all of Europe, immediately threw the internet into a panic Friday morning: A black-and-white live stream of the six-reactor nuclear facility showed it in flames, Twitter users were using Google Satellite images to speculate where the fire originated, and Ukrainian Minister of Foreign Affairs Dmytro Kuleba was tweeting with urgency that an explosion would be “10x larger than Chornobyl.”
Within a few hours it was clear that an incident on or above the scale of the 1986 nuclear disaster at Chernobyl hadn’t happened. What caught fire was not a reactor, nor any part of the facility that contained radioactive waste, but an administrative building used for training. The International Atomic Energy Agency (IAEA) was urging Russian troops to cease fire, the facility had yet to see any changes in radiation, and, by midnight on the east coast, the blazes were extinguished entirely.
Even so, international leaders agreed the attacks represented an escalation by Russia—and while Energoatom, the state plant owner, was reporting that fighting had died down, it also noted it had lost contact with the plant’s managers and control over its nuclear material, per Reuters. The IAEA confirmed this report.
The incident was bad, but it could’ve been potentially disastrous. Why wasn’t it? And what would that have looked like? Motherboard spoke with nuclear physicists to confirm.
Say the ‘worst case scenario’ occurs. Would this be a second Chernobyl?
No, all experts agreed. Rofer tweeted confidently Thursday evening that this was highly unlikely, in part because the reactors at Chernobyl were not protected by containment structures, as those at Zaporizhzhia are.
But Zaporizhzhia’s reactors are also totally different from the ones at Chernobyl. Chernobyl houses Soviet-era RBMK reactors, which use graphite, a highly flammable form of carbon, to facilitate the fission process. The reactors at Zaporizhzhia are VVER reactors—a safer, more modern design that uses water pressure to facilitate fission, and are thus far less likely to catch fire.
“it’s just a totally different a design of reactor,” Rofer said. “At that time, the RBMKs all had a particular design flaw that everybody knew could lead to something like what happened at Chernobyl.”
“No reactors since the RBMKs have been designed that way, including the VVERs and even the existing RBMKs have since been modified,” she said.
The presence of graphite is what made the fires that broke out at Chernobyl so potent.
“It burns, it’s carbon,” said Bob Rosner, founding director of the Energy Policy Institute at the University of Chicago and member of the science and security board at the Bulletin of Atomic Scientists. “When the containment vessel cracked, the carbon caught fire, and the fire was hot enough it lifted a lot of the radioactive waste up into the atmosphere. And that’s what spread.”
A fire at Zaporizhzhia would be unlikely to spread so rapidly, Rosner said, because, simply, “there’s nothing flammable anywhere in that building.”
“It’s very unlikely that you’d have a fire inside of that building,” he added. “The release of radioactivity will be quite localized.”
What now? What risk remains?
Despite his confidence in the safeguards that Europe’s largest nuclear power plant was designed with, Rosner remains alarmed that conflict escalated to an attack on the facility at all.
“It’s kind of astonishing,” he said. “I was asked a few days ago, ‘would the Russians do this?’ I said, ‘no, it’s ridiculous because they hit one of the nuclear parts, damage is going to spread not just in the Ukraine, closer to them, they’re next door.”
Continued conflict around the reactor could forge down any number of pathways to meltdown, leading to a radioactive disaster. It could also just shut down the entire power plant, a scenario that could see enough energy (5,700 megawatts) to power 400,000 Ukrainian households go offline—some 20 per cent of the country’s electrical output comes from nuclear energy from Zaporizhzhia.
“It would be like Con-Ed going dark,” Yurman said. “It would be like all the power plants and in greater New York, Con-Ed just pulling the plug on them.”
By Friday mid-day, it appeared that control over the facility was in the hands of Russia, and Energoatom, the state utility that owns Zaporizhzhia, warned that any messaging coming out of the plants could reflect this reality.
“There is a high probability that the recent speech of the mayor of Enerhodar was recorded under the barrel of a machine gun,” the company said according to the New York Times.
That could threaten typical safety protocols at the facility, as Ukrainian officials warned was the case at Chernobyl last week. For now, Rofer, Rosner and Yurman are taking solace in the fact that the worst didn’t happen.