An International Atomic Energy Agency (IAEA) Safety Aspects of Long Term Operation (SALTO) team of experts has completed a review of long term operational (LTO) safety at unit 1 of the Angra NPP in Brazil. The review mission was requested by nuclear utility Eletronuclear. Two IAEA pre-SALTO missions in 2013 and 2018, followed by a pre-SALTO follow-up in 2022, were previously conducted to review the long term safety of the unit.

Eletronuclear submitted a licence renewal application to the Brazilian Nuclear Regulatory Authority (CNEN – Comissào National de Energia Nuclear) in 2019 to extend the operating lifetime of the 640 MWe unit 1 from 40 to 60 years. The plant, located 150 kilometres west of Rio de Janeiro, went into commercial operation in 1985 and its current operating licence expires in December 2024. The review did not include the 1,350 MWe Angra 2, which started commercial operation in 2001, and the 1,405 MWe Angra 3 still under construction.

The team reviewed the plant’s preparedness, organisation and programmes for safe LTO. The 12-person team comprised experts from Argentina, Bulgaria, Finland, Japan, South Korea, the Netherlands, Slovakia, and the USA, as well as two IAEA staff members. The team held discussions with staff from Angra NPP and conducted plant walkdowns.

“The team noted the progress in measures taken by the operator to ensure the safe LTO of the plant. The professionalism, openness and receptiveness for improvements to meet and move beyond the IAEA safety standards in operation are commendable,” said Gabor Petofi, team leader and IAEA Senior Nuclear Safety Officer. He added that most of the ageing management and LTO activities are already in alignment with IAEA Safety Standards. “We encourage the plant to address the review findings and proceed with the implementation of all remaining activities for safe LTO.”

The team identified several good practices and good performances at the plant that will be shared with the nuclear industry globally, including:

  • The confirmation process to regularly evaluate and improve ageing management programmes.
  • The software tool developed to determine opportunistic inspections of components.
  • The use of artificial intelligence to determine the qualified life of plant equipment.

The team also provided recommendations to further enhance the preparations for safe LTO, including for the plant to consider:

  • Consistently addressing and implementing all ageing management programme attributes for civil structures.
  • Improving the process of temporary design modifications for LTO.
  • Implementing a comprehensive equipment qualification programme.
  • The plant management expressed determination to address the areas identified for improvement and to invite a SALTO follow-up mission in 2026.

“Eletronuclear is strongly committed to satisfy all regulatory requirements and implement all possible improvements that can be derived from international best practices and IAEA Safety Standards” said Abelardo da Cruz Viera, Angra 1 plant manager. “The SALTO findings will help us ensure a safe and reliable completion of LTO activities and improve performance for the next cycle of operation of the plant”.

The team provided its draft report to the plant management and CNEN who will have an opportunity to make factual comments. The final report will be submitted to the plant management, CNEN and the Brazilian Government within three months. This mission was supported by the IAEA’s Technical Cooperation Programme which assists member states in the use of nuclear technology for sustainable socio-economic development.