The Zaporizhzhia nuclear power plant in the middle of the fighting in Ukraine was temporarily cut off from the electrical grid Thursday because of fire damage, causing a blackout in the region and heightening fears of a catastrophe in a country haunted by the Chernobyl disaster.
The plant, Europe's largest, has been occupied by Russian forces since the early days of the war, and continued fighting near the facility has heightened fears of a catastrophe that could affect nearby towns in southern Ukraine — or potentially an even wider region.
On Thursday, the plant was cut off from the grid for the first time in its history after fires damaged the last operating regular transmission line, according to Ukraine's nuclear power agency, Energoatom.
It was not immediately clear whether the damaged line carried outgoing electricity or incoming power, needed for the reactors' vital cooling systems. A backup line supplying electricity from another plant remained in place, Energoatom said. The entire Zaporizhzhia region lost power, according to Yevgeny Balitsky, the Russia-installed governor.
As a result of the damage, the two reactors still in use went offline, he said, but one was quickly restored, as was electricity to the area.
Ukraine says Russia targets nuclear plant with possible “false flag” operation to come
02:46
Still, Thursday's cutoff underscored concerns about the battles around around the plant.
As CBS News senior foreign correspondent Charlie D'Agata reported from Ukraine earlier this month, the plant is located on the front line, on the edge of Russian-held territory on the banks of the Dnipro River.
The government in Kyiv alleges Russia is essentially holding the plant hostage, storing weapons there and launching attacks from around it. Moscow, meanwhile, accuses Ukraine of recklessly firing on the facility, which is located in the city of Enerhodar.
The three regular transmission lines to the plant are out of service because of previous war damage. A loss of power to the Zaporizhzhia reactors' cooling systems could cause a nuclear meltdown, a major concern of experts and residents warily watching the fighting.
"Anybody who understands nuclear safety issues has been trembling for the last six months," Mycle Schneider, an independent policy consultant and coordinator of the World Nuclear Industry Status Report, said before the latest incident at the plant.
Ukraine cannot simply shut down its nuclear plants during the war because it is heavily reliant on them, and its 15 reactors at four stations provide about half of its electricity. Still, an ongoing conflict near a working atomic plant is troubling for many experts who fear that a damaged facility could lead to a disaster.
That fear is palpable just across the river in Nikopol, where residents have been under nearly constant Russian shelling since July 12, with eight people killed, 850 buildings damaged and over the half the population of 100,000 fleeing the city.
Liudmyla Shyshkina, a 74-year-old widow who lived within sight of the Zaporizhzhia plant before her apartment was bombarded and her husband killed, said she believes the Russians are capable of intentionally causing a nuclear disaster.
Fighting in early March caused a brief fire at the plant's training complex that officials said did not result in the release of any radiation. Ukrainian President Volodymyr Zelenskyy says Russia's military actions there amount to "nuclear blackmail."
On Wednesday, Zelenskyy delivered a surprise remote address during a U.N. Security Council meeting, accusing Russia of putting the world on the "brink of radiation catastrophe" by taking military action near the plant, CBS News correspondent Pamela Falk reported.
The Zaporizhzhia nuclear power plant is seen outside the Russian-controlled city of Enerhodar, Ukraine, August 22, 2022.
Reuters/Alexander Ermochenko
No civilian nuclear plant is designed for a wartime situation, although the buildings housing Zaporizhzhia's six reactors are protected by reinforced concrete that could withstand an errant shell, experts say.
The more immediate concern is that a disruption of electricity supply could knock out cooling systems that are essential for the safe operation of the reactors, and emergency diesel generators are sometimes unreliable.
Currently only one of the four lines supplying the plant with power from outside is operational, according to the International Atomic Energy Agency, the U.N.'s nuclear watchdog. External power is essential not just to cool the two reactors still in operation but also the spent radioactive fuel stored in special facilities onsite.
"If we lose the last one, we are at the total mercy of emergency power generators," said Najmedin Meshkati, a professor of civil and environmental engineering at the University of Southern California.
Another concern about the fighting nearby is that pools where spent fuel rods are kept to be cooled are vulnerable to shelling, which could cause the release of radioactive material.
Kyiv told the U.N. atomic agency that shelling earlier this week damaged transformers at a nearby conventional power plant, disrupting electricity supplies to the Zaporizhzhia plant for several hours.
The atomic agency's head, Rafael Mariano Grossi, said Thursday he hopes to send a mission to the plant within "days."
Negotiations over how the mission would access the plant are complicated but advancing, he said on France-24 television after meeting in Paris with French President Emmanuel Macron, who pressed Russian President Vladimir Putin in a phone call last week to allow the U.N. agency to visit the site.
"Kyiv accepts it. Moscow accepts it. So we need to go there," Grossi said.
At a Security Council meeting Tuesday, U.N. political chief Rosemary DiCarlo urged the withdrawal of all military personnel and equipment from the plant and an agreement on a demilitarized zone around it.
He and Schneider expressed concern that the occupation of the plant by Russian forces is also hampering safety inspections and the replacement of critical parts, and is putting severe strain on hundreds of Ukrainian staff who operate the facility.
"Human error probability will be increased manifold by fatigue," said Meshkati, who was part of a committee appointed by the U.S. National Academy of Sciences to identify lessons from the 2011 nuclear disaster at Japan's Fukushima nuclear plant. "Fatigue and stress are unfortunately two big safety factors."
If an incident at the Zaporizhzhia plant were to release significant amounts of radiation, the scale and location of the contamination would be determined largely by the weather, said Paul Dorfman, a nuclear safety expert at the University of Sussex who has advised the British and Irish governments.
The massive earthquake and tsunami that hit the Fukushima plant destroyed cooling systems which triggered meltdowns in three of its reactors. Much of the contaminated material was blown out to sea, limiting the damage.
The April 26, 1986, explosion and fire at one of four reactors at the Chernobyl nuclear plant north of Kyiv sent a cloud of radioactive material across a wide swath of Europe and beyond. In addition to fueling anti-nuclear sentiment in many countries, the disaster left deep psychological scars on Ukrainians.
Zaporizhzhia's reactors are of a different model than those at Chernobyl, but unfavorable winds could still spread radioactive contamination in any direction, Dorfman said.
"If something really went wrong, then we have a full-scale radiological catastrophe that could reach Europe, go as far as the Middle East, and certainly could reach Russia, but the most significant contamination would be in the immediate area," he said.
That's why Nikopol's emergency services department takes radiation measurements every hour since the Russian invasion began. Before that, it was every four hours.