Regulatory approval for SERAW decommissioning work
Bulgaria’s Nuclear Regulatory Agency has issued a ten-year licence to the State Enterprise Radioactive Waste (SERAW) to continue dismantling Kozloduy units 3 and 4. The authorisation covers the next phase of decommissioning at the Kozloduy nuclear site. It sets requirements related to nuclear safety, radiation protection, physical security and radioactive-waste management.
The licence provides SERAW with a regulatory framework for the dismantling activities. The work is expected to proceed under the specified safety and waste-management conditions.
Kozloduy closure timeline and remaining operating reactors
Kozloduy units 3 and 4 were permanently closed on 31 December 2006, shortly before Bulgaria joined the European Union. Their shutdown was part of commitments made during the country’s EU accession process. Units 1 and 2 had already been shut in 2002.
The site’s two remaining reactors, units 5 and 6, continue to provide the core of Bulgaria’s low-carbon baseload generation. Their operating licences extend to 2047 and 2051, respectively. Continued modernisation, safety assessments and regulatory approval are required for ongoing operation.
Radiana repository support and waste handling limits
The new dismantling phase will be supported by Bulgaria’s national radioactive-waste repository at Radiana, near Kozloduy. The facility entered operation in April 2026. It is designed to receive processed low- and intermediate-level waste, including material generated by dismantling the four closed reactors.
Radiana is not authorised to accept spent nuclear fuel or high-level radioactive waste. Those materials require separate handling, storage and long-term disposal arrangements, creating a continuing strategic requirement beyond the current dismantling programme.
Scope of decommissioning activities under the ten-year window
Decommissioning is described as a long-duration industrial project rather than a simple plant-closure exercise. It involves radiological characterisation, segmentation and removal of contaminated equipment, along with waste treatment and transport controls. Environmental monitoring and a complete traceable record for regulators are also required.
The ten-year licence is intended to provide a stable regulatory window for the next stage. Cost and schedule performance will depend on equipment condition, the volume and classification of radioactive material, and the availability of qualified contractors. Bulgaria must carry out this work while maintaining high operating standards at Kozloduy units 5 and 6, which remain central to electricity exports and regional supply position.
