Second Leningrad unit defuelled

23 August 2023

Defuelling of the second of two shut-down RBMK reactors at the Leningrad nuclear power plant in Russia has now been completed, an important step in the process to decommission the units.

Leningrad 2: now defuelled (Image: Rosatom)

Leningrad 1 and 2 were shut down in 2018 and 2020, respectively, after 45 years of operation. Defuelling of unit 1 was completed in August 2021, while defueling of unit 2 began in October that year. All 3361 fuel assemblies - 1693 from unit 1 and 1668 unit 2 - have now been unloaded into special storage pools.

Some partially used assemblies - those with more than 50% of their 'burn-up' still remaining - will be used in Leningrad 3 and 4, which are scheduled to remain in operation until 2025 and 2026, respectively. This has economic benefits, according to plant director Vladimir Pereguda, from avoiding the need to buy new fuel and reducing the costs of managing the used fuel assemblies. The rest will be moved to the station's used fuel storage facility.

Public consultations on plans for the final decommissioning of the two shut-down reactors, including the environmental impact, were completed in July, a necessary step before documents can be submitted for state environmental approvals and for Russia's Federal Service for the Supervision of Environment, Technology and Nuclear Management (Rostekhnadzor) to issue a licence for the work.

The Soviet-designed RBMK (reaktor bolshoy moshchnosty kanalny, high-power channel reactor) is a water-cooled reactor with individual fuel channels and using graphite as its moderator and is also known as the light-water graphite reactor. The design has been recognised as having several shortcomings, and today only eight - all in Russia - remain in operation. Major modifications have been made to those RBMK units that are still in operation to improve their safety following the 1986 Chernobyl disaster.

Researched and written by World Nuclear News