An International Atomic Energy Agency (IAEA) team of experts today completed a review of long term operational safety at Unit 1 of the Atucha Nuclear Power Plant (NPP) in Argentina.
The Safety Aspects of Long Term Operation (SALTO) mission was requested by plant operator Nucleoelectrica Argentina S.A (NA-SA). It continues a comprehensive IAEA evaluation of the unit in recent years. Two IAEA Pre-SALTO missions in 2016 and 2018, followed by a Pre-SALTO follow-up in 2021, were previously conducted to review the long term safety of the unit.
NA-SA is currently preparing to submit a license renewal application to the Argentinian Nuclear Regulatory Authority (ARN) to extend the operating lifetime of the 362 Megawatt electric (MWe) Unit 1 by 20 years. The plant, located 100 km north-west of Buenos Aires, went into commercial operation in 1974 and its current operating licence expires in 2024. The 745 MWe Unit 2 of Atucha NPP started its commercial operation in May 2016 and was not part of the review.
During the ten-day mission from 27 February to 7 March, the team reviewed the plant’s preparedness, organization and programmes for safe long term operation (LTO). The mission was conducted by a twelve-person team comprising experts from Belgium, Brazil, Japan, Slovenia, Spain, Sweden, the United States, and two IAEA staff members. The team had in depth discussions with staff from the Atucha NPP and conducted plant walkdowns during the review.
“The team noted the measures taken by the operator to ensure the safe LTO of the plant. Additionally, the professionalism, openness and receptiveness exhibited by the plant staff towards suggestions for improvement are commendable,” said Gabor Petofi, team leader and IAEA Senior Nuclear Safety Officer. “Many 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 good practices and good performances that will be shared with the nuclear industry globally, including:
- The qualification of coatings designed to ensure integrity of the containment building.
- Comprehensive condition assessment reports for safety related structures, systems and components.
- Objective score cards used for evaluation of applications for internal vacancies.
The team also provided recommendations to further enhance the preparations for LTO safety, including:
- The plant should provide a systematic safety assessment to identify reasonable safety improvements for the operation period beyond 2024.
- The plant should complete and implement the qualification programme for electrical components inside the containment.
- The plant should improve the implementation of ageing management of civil structures.
The plant management expressed a determination to address the areas identified for improvement and invite a SALTO Follow-up mission in 2026.
“The IAEA and NA-SA teams showed a strong commitment to the successful implementation of the SALTO mission, working in a professional and collaborative environment, sharing information and experience,” said Eduardo Arostegui, site manager at Atucha NPP. “The SALTO findings will help us to ensure a safe and reliable development of LTO activities and will also improve performance for the second cycle of operation of Atucha I”.
The team provided a draft report to the plant management and ARN at the end of the mission. The plant management and ARN will have an opportunity to make factual comments on the draft. A final report will be submitted to the plant management, ARN and the Argentinian Government within three months.
Background
Information on SALTO missions can be found here.
A SALTO peer review is a comprehensive safety review addressing strategy and key elements for the safe long term operation of nuclear power plants. They complement OSART missions, which are designed as a review of programmes and activities essential to operational safety. Neither SALTO nor OSART reviews are regulatory inspections, nor are they design reviews or substitutes for an exhaustive assessment of a plant's overall safety status.
LTO of nuclear power plants is defined as operation beyond an established time frame determined by the license term, the original plant design, relevant standards or national regulations. As stated in IAEA safety standards, to maintain a plant’s fitness for service, consideration should be given to life limiting processes and features of systems, structures and components (SSC), as well as to reasonably practicable safety upgrades to enhance the safety of the plant to a level approaching that of modern plants.