A key stage in preparation for the decommissioning of units 1&2 at Russia’s Leningrad NPP has been completed with removal of the last fuel assembly (FA) from unit 2 RBMK-1000 reactor. Defuelling at unit 1 was completed in August 2021. In total, workers removed 3,361 fuel assemblies: 1,693 from unit 1 and 1,668 from unit 2.

The two units ceased operation in 2018 and 2020 after 45 years of operation.

The fuel was unloaded into special holding pools. Just under half of the fuel that was not fully burned will be re-used in the RBMK reactors still operating at units 3&4. The rest will be transferred to the station's used nuclear fuel storage facility. Vladimir Pereguda, director of the Leningrad NPP explained that re-using the partially burned has a significant economic effect. “We – do not need to buy new fuel and this further reduces the costs of handling used fuel assemblies.”

Currently Leningrad NPP has four units in operation – the original units 3&4 with RBMK-1000 reactors, as well units 5&6 with new VVER-1200 units, which began operation in 2018 and 2021, replacing units 1&2. Two more VVER-1200 units (units 7&8) will eventually replace the units 3&4.These are planned to begin operation in 2030 and 2032.

Image: Leningrad 2 reactor hall (courtesy of Rosatom)