Inside the Battle to Repair Chornobyl’s Damaged Confinement

A Russian drone strike on Chornobyl’s New Safe Confinement destroyed its hermetic seal and ventilation system, sparking a two-week fire inside the cladding and raising fears of corrosion. EBRD officials warned Kyiv Post that delays in repairs could jeopardize the entire €2 billion structure. Make us preferred on Google Share Facebook X (Twitter) LinkedIn Bluesky Email Copy Copied European Bank of Reconstruction and Development (EBRD) President Odile Renaud-Basso speaking to Kyiv Post in Kyiv in April 2026. (Photo courtesy of Howard Johnson / EBRD press service) Content Share Facebook X (Twitter) LinkedIn Bluesky Email Copy Copied Flip Make us preferred on Google The European Bank for Reconstruction and Development (EBRD) spent 20 years designing the New Safe Confinement at Chornobyl, securing funding from 45 countries, overseeing its construction, and ultimately handing the project over to Ukraine. The 35-story arch-shaped structure was built in two sections before being moved into place over reactor No. 4 at the Chornobyl Nuclear Power Plant (NPP). Designed to last 100 years, the €2.1 billion ($2.5 billion) confinement was meant to contain radiation while engineers dismantled both the remains of the reactor and the original sarcophagus hastily built after the Chornobyl disaster. Follow our coverage of the war on the @Kyivpost_official . “We thought [our mission] was accomplished. There was a ceremony where we gave back the keys to the Ukrainian authorities after the New Safe Confinement was built,” EBRD President Odile Renaud-Basso told Kyiv Post during her visit to Kyiv, which marked the 40th anniversary of the nuclear catastrophe. But in February 2025, a Russian drone damaged the structure, tearing a hole in the roof and later burned through the cladding roughly the size of 18 parked cars.  “There is a hole, and there has also been a big fire that took place following the drone, and that really impaired the functionalities of the New Safe Confinement,” Renaud-Basso added. Russia’s drone strike did more than create a hole – it severely damaged the system protecting the nuclear facility, launching a race against time to prevent corrosion spreading through the massive shelter over Reactor No. 4. Other Topics of Interest US Sanctions Cuban Military Corporation The United States has imposed new sanctions on Cuba’s Gaesa conglomerate, which controls a large share of the island’s economy, along with foreign companies linked to its operations. The measures, part of a broader pressure campaign, prompted Canadian firm Sherritt to exit the country. Cuban officials condemned the move, while Washington signaled further sanctions may follow. The EBRD is assessing repairs to the confinement before humidity, fire damage, and exposure further weaken the structure, which was designed to last a century. While no radiation leak has been detected, repair costs could exceed €500 million ($585 million), according to the EBRD’s preliminary estimates. Donors are only beginning discussions on how to finance the effort, while the EBRD says it’s better to act now to prevent a larger, more expensive catastrophe. Kyiv Post spoke with EBRD President Renaud-Basso and Balthasar Lindauer, director of the EBRD Nuclear Safety Department, who detailed the severe damage inflicted by the Russian drone strike on the NSC and the resulting risks to the construction. An aerial view of the Chornobyl Nuclear Power Plant, with the New Safe Confinement arch visible on the left, in 2026. (Photo by the EBRD press service) Patching the hole in the confinement was easy enough – but the main problem was the resulting fire that spread through the cladding, according to Lindauer. “[The drone strike in February] created penetration of 15 square meters [161 square feet], followed by a fire caused by the explosion from remaining fuel in the drone,” Lindauer told Kyiv Post on the sidelines of the EBRD delegation’s visit to Kyiv. “If that was the only problem, it would be relatively easy to fix,” he added. Lindauer said the drone caused a 15-square-meter breach in the inner and outer cladding and damaged around 200 square meters (2,153 square feet) of panels. “The biggest problem was that the fire propagated through the cladding of the New Safe Confinement over a very large area. The firefighters needed two weeks to extinguish the fire, which was smoldering in the various layers of this outer cladding. The cladding lost its property,” Lindauer explained. The cladding of the New Safe Confinement at the Chornobyl Nuclear Power Plant. (Photo courtesy of the EBRD press service) Designed as a protective “sandwich,” the NSC’s cladding consists of inner and outer metal panels that create a hermetically sealed gap. This space is ventilated to maintain a slight overpressure, ensuring radioactive contaminants remain contained. Beyond insulation, this pressurized zone contains essential sensors that monitor for humidity and temperature to protect the arch from corrosion. This is where the drone hit, damaging the system from the outside. The strike didn’t kill the ventilation system; it just stopped working. Outside air is now leaking in and rusting the metal. Engineers can’t fix it or paint over the rust because the radiation is too high for workers to get close. “In similar structures like the Eiffel Tower, every 10 years or so you send workers to repaint them with an anti-corrosion coating so that nothing happens. This is not something that you could do here because of extreme radiation levels,” Lindauer continued. The interior of the New Safe Confinement at the Chornobyl Nuclear Power Plant, showing the 1986 shelter and crane scaffolding beneath the arch, in 2026. (Photo by the EBRD press service) The current construction is painted with anti-corrosion coatings that expire in a few years, Lindauer added, so the repairs should start now. “We said the deadline is before 2030. The experts who have built the New Safe Confinement estimate that this needs to be done by 2030 in order to avoid corrosion of the structure that would have a long-term impact. That would really destroy all the benefits of this infrastructure and would require another reconstruction,” EBRD President Renaud-Basso told Kyiv Post. After a preliminary assessment of the damage, the EBRD team decided that, instead of repairing the old cladding where the hole is, it is better to add an additional layer of cladding on top of it over a “large area.” Workers will need special shielding to work under radiation levels, which is no ordinary job. “You cannot send workers for long periods of time in there,” Lindauer told Kyiv Post. But the drone damaged not only the cladding, but also the membrane connecting the two parts of the confinement. “Two parts were then joined before moving. This joint has also burned,” Lindauer said. The membrane consists of a “very particular material,” which is “difficult to find,” he added. “It all needs to be repaired on the outside, but also on the inside,” he said. And finally, the fire burned the membranes connecting the arch to the foundations. The cranes attached to the arch to perform work inside the reactor are currently not operational, and it is not yet known whether they were damaged by the drone strike. The cranes in the New Safe Confinement at the Chornobyl Nuclear Power Plant in 2026. (Photo by the EBRD press service) Because the full extent of the damage is still being assessed, the half-billion-euro price tag could rise once the final cost estimate is finalized. “We cannot exclude it will rise, but we hope this is the right order of magnitude,” Renaud-Basso told Kyiv Post. “We need to do further technical, more detailed analysis, and we’ll do that in the coming years.” But there is one piece of good news. “The biggest worry we had was that through the drone strike, the structure would be deformed. This doesn’t appear to be the case,” Lindauer explained; another piece of good news is that, for now, the radiation does not escape confinement. Now, it’s time for the EBRD to fundraise for the NSC – again. European Bank of Reconstruction and Development (EBRD) President Odile Renaud-Basso speaking to Kyiv Post in Kyiv in April 2026. (Photo courtesy of Howard Johnson / EBRD press service) The EBRD has allocated funds to start preliminary work but is now eyeing donors to support the project, Renaud-Basso told Kyiv Post. The EBRD allocated €30 million ($35.2 million) to the International Chernobyl Cooperation Account (ICCA) – funds from this bank account will be used to start preliminary work on engineering and early procurement to support the restoration of NSC functionality. Fourteen donors – including the UK, the EU, Canada, France, and Norway – have already contributed €75 million ($88 million) to the ICCA, according to data shared by the EBRD with Kyiv Post. But the total repair costs are estimated to exceed €500 million ($585 million). Kyiv Post spoke with the EBRD president on April 27 – at that time, she said no large financial commitments had been signed. Foreign diplomats and Moldovan President Maia Sandu, as well as Renaud-Basso, also attended the ceremony commemorating the anniversary of the nuclear incident. The EBRD president said that “it was emotional” to return to Chornobyl 40 years after the disaster. “And then it was also a good moment to explain what is the state of play with this new safe confinement and the need to invest to repair it following this drone attack,” she added. Renaud-Basso said she wanted to increase awareness of why the repair should be financed, and especially to convince the G7 countries that were major donors to the initial project to construct the NSC. “We had already had some discussions with G7 finance ministries and G7 foreign ministers… we now need to fine-tune them and secure more concrete commitments,” she said. The key argument? Better a small repair bill now than a new, costlier construction bill later. “It was important to explain the timing and the fact that sometimes you need to invest in preventing other catastrophe – or even more investment is needed,” Renaud-Basso said. Meanwhile, the International Atomic Energy Agency (IAEA) participates in assessing the situation but doesn’t have the mandate to do fundraising, Renaud-Basso said. European Bank of Reconstruction and Development (EBRD) President Odile Renaud-Basso speaking to Kyiv Post in Kyiv in April 2026. (Photo courtesy of Howard Johnson / EBRD press service) Under Soviet rule, the reactor at Chornobyl was designed with flaws, and nuclear operators were not informed of its instabilities and safety violations, according to the International Nuclear Safety Advisory Group (INSAG) report . The result was one of the most notorious nuclear disasters in both human and Ukrainian history. Nearly 40 years later, a Russian drone – launched as part of the 2022 invasion – punched a hole in the structure built to protect the world from that very disaster. The EBRD led the construction of this unprecedented shield; now, it must lead repairs after an attack once thought impossible in the post-WWII era. “I think it’s completely unacceptable to have a drone on the nuclear [object]… It’s highly irresponsible, thinking about the long-term consequences for the region. It’s so shocking,” Renaud-Basso said. Olena Hrazhdan is the Business Reporter at Kyiv Post, covering Ukraine’s markets, business, and economic policy. While she reports broadly on economic issues, her core focus is banking, finance, monetary and fiscal policy. Olena previously wrote for leading Ukrainian business media and became a Fellow of the International Monetary Fund’s Journalism Fellowship in 2024.