Bulgaria’s Nuclear Regulatory Agency has granted the State Enterprise Radioactive Waste a ten-year licence to continue dismantling units 3 and 4 at the Kozloduy nuclear site.
The licence allows the state enterprise, commonly known as SERAW, to proceed with the next phase of decommissioning under requirements covering nuclear safety, radiation protection, physical security and radioactive-waste management.
Kozloduy units 3 and 4 were permanently closed on 31 December 2006, shortly before Bulgaria joined the European Union. Their closure formed part of the 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 currently extend to 2047 and 2051, subject to continuing modernisation, safety assessments and regulatory approval.
The new decommissioning phase will be supported by Bulgaria’s national radioactive-waste repository at Radiana, near Kozloduy. The facility entered operation in April 2026 and is designed to receive processed low- and intermediate-level waste, including material generated by dismantling the four closed reactors.
Radiana is not authorised to receive spent nuclear fuel or high-level radioactive waste. Those materials require separate handling, storage and long-term disposal arrangements, leaving Bulgaria with a continuing strategic requirement beyond the current dismantling programme.
Decommissioning is a long-duration industrial project rather than a simple plant-closure exercise. It requires radiological characterisation, segmentation and removal of contaminated equipment, waste treatment, transport controls, environmental monitoring and a complete traceable record for regulators.
The ten-year licence provides a stable regulatory window for the next stage, but cost and schedule performance will depend on the condition of the equipment, 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 units 5 and 6, which remain central to the country’s electricity exports and regional supply position.
