Name of the Project
Chernobyl Nuclear Reactor 4 new safe confinement (NSC) structure repair.

Location
Ukraine.

Project Owner/s
Chernobyl Shelter Fund, which is being managed by the European Bank for Reconstruction and Development.

Project Description
The NSC is the largest movable land-based structure ever built. It has a 257 m span, is 162 m long, 108 m high and weighs 36 000 t when equipped. Designed for a 100-year service life, it was built to enable the dismantling of the ageing shelter hastily built over Chernobyl’s destroyed Unit 4 after the 1986 accident, while also supporting the management of radioactive waste.

The structure has been engineered to operate in extreme conditions, including temperatures from -43 °C to +45 °C, a class-three tornado and an earthquake of magnitude 6. The structure was assembled nearby and then moved into place over Unit 4, with the sliding operation completed on November 29, 2016.

In February 2026, the NSC suffered a drone strike. A preliminary technical assessment by Bouygues Travaux Publics and Vinci Construction Grands Projets completed in March 2026 determined that the NSC will require temporary protection measures and longer-term restoration work. 

The proposed programme includes weatherproofing the roof, repairing damaged steelwork and external cladding, restoring airtightness in the annular space, repairing or replacing damaged sealing joints, reinstating leak-tight membranes, recommissioning the ventilation system and restoring the main crane system. 

The assessment sets restoration of full functionality by 2030 as the main objective, mainly to limit corrosion risk to the steel arch and preserve long-term safety performance.

Potential Job Creation
Not stated.

Capital Expenditure
The cost of the repairs is still too early to provide a firm estimate; however, indications are that repairs could cost about €500-million. A more reliable estimate will depend on detailed engineering, procurement routes, market conditions, security constraints, and alignment with regulatory and donor requirements. 

Planned Start/End Date
The 2030 target depends on site access and security conditions allowing for work to proceed, with construction needing to start by about the end of 2027. However, the schedule remains uncertain until detailed design, regulatory approvals and procurement plans are finalised. 

Latest Developments
The schedule remains uncertain until detailed design, regulatory approvals and procurement plans are finalised. 

Key Contracts, Suppliers and Consultants
Bechtel (project management) and Novarka joint venture comprising Vinci Construction Grands Projets and Bouygues Travaux Publics (NCS construction).

Contact Details for Project Information
Nuclear Safety Department of the European Bank for Reconstruction and Development, tel +44 20 7338 7195, fax +44 20 7338 7175 or email nuclearsafety@ebrd.com.