Long-term safety review for Angra 1

14 May 2018

A team of International Atomic Energy Agency (IAEA) experts has completed a Pre-SALTO (Safety Aspects of Long Term Operation) review at Brazil's Angra 1 nuclear power plant. Plant operator Eletrobras Eletronuclear is preparing to apply to extend the pressurised water reactor's operating lifetime from 40 to 60 years.

Angra 1 and 2 (Image: Eletronuclear)

The 13-strong team included experts from Argentina, China, the Czech Republic, France, Japan, South Africa and the USA as well as two IAEA staff members. It reviewed the plant's organisation and programmes related to long-term operation (LTO), including human resources and knowledge management using IAEA safety standards. The review began on 2 May and was completed on 11 May.

The IAEA team observed that the plant had "made progress" in the field of ageing management and preparedness for safe LTO. It said plant management demonstrated a commitment to making further progress and that the LTO project addresses many topics as recommended by IAEA safety standards. The team found plant staff to be professional, open and receptive to suggestions for improvement.

Good practices and performances identified by the team include the plant's implementation of appropriate measures to address environmentally assisted fatigue of safety significant components for LTO; the development of a master list of equipment subject to environmental qualification; and the plant's active support of educational activities, including an internship programme for potential employees. These will be shared with the nuclear industry globally.

Recommendations for enhancing LTO safety made by the IAEA team include that the plant should: perform a comprehensive periodic safety review; ensure that ageing of active and short-lived structures and components within the scope of LTO are properly assessed and managed; and fully implement a comprehensive environmental qualification programme.

Angra 1's management said it was committed to implementing the recommendations and requested that the IAEA schedule a SALTO mission in November 2020.

Angra 1 reached criticality in 1982 and entered commercial operation in 1985. The reactor has a design capacity of 626 MWe (net capacity 60 MWe). Eletrobras Eletronuclear also operates Angra 2, a 1275 MWe (net) PWR which began commercial operation in 2001. The company is preparing an application to renew Angra 1's licence, which would give it a 60-year operating period. The application must be submitted by 2019.

A SALTO peer review is a comprehensive safety review addressing strategy and key elements for the safe long-term operation of nuclear power plants. SALTO missions complement IAEA Operational Safety Review Team (OSART) missions which are designed as a review of programmes and activities essential to operational safety. SALTO peer reviews can be carried out at any time during the lifetime of a nuclear power plant, although according to the IAEA the most suitable time lies within the last ten years of the plant's originally foreseen operating period. SALTO and OSART reviews are carried out at the request of the IAEA member country in which the review is to take place.

Researched and written
by World Nuclear News