IAEA reviews long-term safety of Armenian plant

12 December 2018

An International Atomic Energy Agency (IAEA) team of experts has completed a review of long-term operational safety at the Armenian Nuclear Power Plant (ANPP) at Metsamor.

An aerial view of the Metsamor plant (Image: ANPP)

The 12-member team reviewed the plant's preparedness, organisation and programmes related to long-term operation (LTO) against IAEA safety standards. The review, which followed preliminary reviews in 2013 and 2016 - began on 27 November and was completed on 6 December.

The Metsamor plant comprises two Russian-built 376 MWe VVER reactors which started operating in 1976 and 1980, respectively. Both units were taken off line in 1988 due to safety concerns regarding seismic vulnerability, although they both continued to operate and had not sustained any damage in a major earthquake in the region earlier that year. Unit 2 was restarted in 1995, and is subject to ongoing safety improvements. Unit 1 is now being decommissioned.

In 2011, the Armenian Nuclear Regulatory Authority granted the plant an operating licence extension until 2021, subject to annual safety demonstration since 2016. The plant is preparing to submit an application for a second licence renewal to extend its operating lifetime until 2026.

A SALTO (Safety Aspects of Long Term Operation) peer review addresses strategy and key elements for the safe long-term operation of nuclear power plants. SALTO missions complement IAEA Operational Safety Review Team (OSART) missions review 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.

The SALTO team said the plant has begun addressing the main findings of the previous missions, which included the need to complete necessary safety analysis updates and the identification of components requiring a new safety demonstration for long-term operation. The team also found that, in preparation for extended operation, the operator had assessed the fitness for service of safety-related components and decided on an extensive replacement and upgrading programme. The team also said the operator had made progress in managing ageing and other technical areas relevant to safe LTO, and found plant staff to be professional, open and receptive to suggestions for improvement.

The team identified several good practices and performances that will be shared with the nuclear industry globally. These include weekly training for plant managers in LTO areas for plant modernisation. The plant also employs a comprehensive chemistry monitoring process that provides information for an ageing management programme, as well as a crack detection monitoring programme to ensure the integrity of the dry used fuel storage facility.

The mission team provided several recommendations for further enhancing LTO safety at Metsamor, including that the plant should keep the safety analysis report updated throughout the LTO period. It should also ensure that the methodology for determining the scope of LTO includes all relevant systems, structures and components. The plant should also ensure the adequate environmental qualification of electrical and instrumentation and control equipment is maintained.

The team provided a draft report to the plant management at the end of the mission. A final report will be submitted to the plant, the Armenian Nuclear Regulatory Authority and the government within three months.

The plant management said it was committed to implementing the recommendations and requested that the IAEA schedule a follow-up mission in 2020.

ANPP Chief Engineer Artur Grigoryan said, "The results of the SALTO mission are essential for us to make sure we are going in the right direction. We will need to analyse the team's findings and take appropriate steps to further enhance our safety for LTO."

Researched and written by World Nuclear News