The Leningrad Nuclear Power plant has strengthened operational safety in response to a review of one of its elderly reactor units conducted by the International Atomic Energy Agency, the UN’s nuclear watchdog, in 2017.

In that year, the IAEA’s so-called Operational Safety Review Team spent 17 days at the plant inspecting its No 4 reactor, one of Russia’s aging graphite moderated RMBK-1000 units, which Rosatom, Russia’s state nuclear corporation, has scheduled for decommissioning by 2025.

As a result of its visit, the UN team issued a raft of recommendations including strengthening the reactor’s radiation safety program, conducting regular reviews of its chemistry safety and control regimes, and adopting other strategies aimed at ensuring continuous safety improvements.

At the end of last month, the three-person IAEA team – comprising one expert from South Africa and two officials from the IAEA – wrapped up a four-day follow up visit to the reactor.

“Notable efforts and actions were taken to address the findings of the 2017 mission, indicating a strong commitment to continuously improving safety by the plant management,” said team leader Fuming Jiang, a senior nuclear safety officer at the IAEA, according to the World Nuclear News. “We encourage the plant management to continue this momentum to take the performance to the next level.”

The follow-up visit found improvements to control of movable items in some sensitive areas in the plant; the use of human performance tools; and the plant chemistry surveillance and control program.

However, the team noted that more time is required to demonstrate that improvements are fully effective and sustained in the use of forward-looking and proactive performance indicators at the plant, and in the radiation contamination control program.

Earlier this year, the Leningrad Nuclear Power Plant began decommissioning its oldest reactors. The four Chernobyl-style RBMK units, which were launched throughout the 1970s and early 1980s, will be replaced by newer reactors under construction at the Leningrad Nuclear Power Station II, which like the older plant is located 70 kilometers west of St Petersburg.

The older plant’s No 1 reactor was taken out of service in January, marking the first time Russia has sought to decommission one of its 11 RBMK units. It’s expected that safely dismantling these reactors could take as long as 50 years because the technology for dealing with their graphite moderated systems doesn’t yet exist.

During its visit last month, the IAEA team provided a draft of its report to the management of the Leningrad nuclear plant. It will submit the final report to the Russian government within three months, World Nuclear News reported.

Vladimir Pereguda, the director of the Leningrad plant, said that technicians there had been cooperating with the IAEA’s Operational Safety Review Team since 2014, adding in a statement that the cooperation” has proven to be very beneficial to our efforts to continuously strengthen operational safety performance.”