The International Atomic Energy Agency (IAEA) mission, which visited the Chornobyl Nuclear Power Plant last week, documented the consequences of the russian drone attack on the Arch of the New Safe Confinement (NSC).

The attack, that took place on 14 February 2025, caused damage to the integrity of the NSC's outer cladding and a prolonged fire, which significantly damaged the Arch's inner sealing membrane.

In particular, damage to the sealing cladding of the NSC led to:

• non-compliance with the design requirements for the tightness of the main protective structure and its function as a barrier that prevents the spread of radioactive substances into the environment;
• rendering proper airflow control impossible in accordance with the design and technological requirements necessary to maintain the required air pressure/vacuum in the NSC space;
• violation of the requirements for preventing atmospheric precipitation from entering the NSC space.

At the same time, the radiation level at the Chornobyl industrial site remains stable and within the established limits.

IAEA representatives are permanently present at ChNPP and monitor the current safety status of the plant's facilities. At Ukraine's request, the mission additionally conducted a comprehensive safety assessment of the NSC specifically in the context of the russian attack.

As it is noted in the IAEA report, experts confirmed the loss of some of the NSC's key safety functions, including its containment capability. At the same time, the mission did not find any irreversible damage to the supporting structures or monitoring systems.

"Since February 2025, Ukraine, together with its international partners, has been overcoming the consequences of the russian attack. An assessment of the damage has been carried out, about which we have repeatedly informed Ukrainians and the International Community. The safety situation at the ChNPP site is under constant control by Ukrainian and International experts, and there are currently no prerequisites for its deterioration.

In October, we have already completed work to eliminate the opening in the outer cladding of the confinement. In order to fully restore the NSC functioning it is necessary to implement a set of measures, including the replacement of the sealing membranes ensuring a tight connection between the Arch and the concrete structures of the ChNPP and the NSC, as well as the restoration of the full tightness of the outer cladding. This is a complex technical task, given the high levels of radiation in the area where the work is being carried out", said Chornobyl NPP General Director Serhii Tarakanov.

According to him, the European Bank for Reconstruction and Development (EBRD) has engaged experts from the French companies Bouygues Travaux Publics and VINCI Construction Grands Projets, members of the Novarka consortium, which designed and built the NSC. The experts are conducting a comprehensive study of the technical condition of the Arch's structures and technological systems, identifying current and long-term risks, the scope of necessary restoration work, and formulating recommendations on the policy and strategy for NSC restoration. A preliminary assessment was presented recently in London at a meeting of the Assembly of the International Chornobyl Cooperation Account.

The Chornobyl NPP, the EBRD and French companies will continue to work together to restore the full functionality of the confinement.