Shelter Arch at Chornobyl NPP completely closed following Russian shahed hit in Feb
Completion of temporary repairs to the outer portion of the New Safe Confinement (NSC) Shelter arch over Unit 4 of the Chornobyl Nuclear Power Plant following the Russian nuclear attack in February of this year was scheduled for October 3, IAEA Director General Rafael Mariano Grossi announced.
“The IAEA team at the Chornobyl site was informed that temporary repairs on the outside of the NSC arch are expected to be completed today following the February attack, meaning it will be fully covered from the outside,” Grossi’s statement reads.
As reported, a Russian drone strike on the NSC (New Safe Confinement) Shelter on the morning of February 14 and the resulting fire damaged the NSC's outer shell and equipment in the crane maintenance garage. In early May, the IAEA Director General noted that approximately 330 holes, each averaging 30-50 cm in size, had formed in the outer skin of the NSC arch as a result of emergency work following the drone attack in February of this year.
Grosi also recalled in his statement this Friday that this week, due to a Russian strike on the 330 kV Slavutych distribution substation, located approximately 40 km away, the power line that supplied electricity to the NSC was disabled.
“Off-site power to the NSC – a large structure built to prevent any radioactive release from the reactor destroyed in 1986 and to protect it from any external hazard – was only restored some 16 hours later. During this time, the facility – which was severely damaged by a drone in February – had no access to back-up EDG electricity for some three hours on Wednesday evening, resulting in a partial blackout to the NSC,” the IAEA Director General noted.
According to him, the IAEA team was informed that radiation monitoring and ventilation of the NSC remained operational throughout the blackout, via an interconnection to the systems of reactor units 3 and 4, which remained connected to the main electrical grid. The team was also informed that radiation levels remained normal during the entire event, which was confirmed by the IAEA’s own measurements.
All other nuclear facilities at the Chornobyl site continued to receive off-site power from other power lines without interruption. However, the plant reported fluctuations in off-site power affecting the other facilities at the site during the event and continues to assess the situation.
“The Slavutych 330 kV power line remains disconnected, and the town with the same name – where most plant staff live – has no electricity, relying instead on diesel generators,” Grossi stated.
As reported, on July 1, 2025, the fifth grant agreement was signed between the European Bank for Reconstruction and Development (EBRD) and the State Specialized Enterprise (SSE) Chornobyl Nuclear Power Plant for the implementation of a project that includes an analysis of the damage caused and the development of an action plan for the temporary repair of the outer cladding and sealing membrane of the New Safe Confinement.
Even with adequate funding, the full restoration of the NSC is expected to take several years. However, during this process, significant attention will be paid not only to technical aspects, but also to ensuring maximum safety for the environment, as well as for people working at the Chornobyl Nuclear Power Plant and in the exclusion zone.