A special protective cover has now been erected at Russia’s Nerpa shipyard in the town of Snezhnogorsk, Murmansk Region, to enable used fuel to be unloaded from the Lepse floating technical base, according to the Joint Stock Company Federal Centre for Nuclear and Radiation Safety (JSC FCNRS).
Lepse was used to refuel the nuclear icebreaker fleet from 1963 to 1981. Since 1981, it has been used for the storage of used fuel and radioactive waste. It was officially taken out of service in 1988, but currently holds 639 used fuel assemblies, some of which have been damaged, which complicates the unloading procedure.
The decommissioning of Lepse, which began in 1988, is being carried out with the support of the European Bank for Reconstruction and Development (EBRD).
In 2014, Lepse was moved to a special dock at the Nerpa shipyard, where storage is being built for the bow section. Some sections are being transported to storage sites in Murmansk by the newly commissioned specialist ship, Itarus, built for Russia by Italy. The new shelter over Lepse’s dry dock will include a workshop for removing the used fuel assemblies, which will then be sent for reprocessing at the Mayak Chemical Combine in the Urals Chelyabinsk Region.
JSC FCNRS began work to recycle parts of the Lepse vessel in 2008 and the disposal project is being implemented in stages. The preparatory stage lasted until 2013. After the partially reconstructed vessel was towed to its special dock, its superstructure was dismantled. After this, the hull was disassembled, block-packs were formed around the fore and aft sections of the vessel. In November 2016, the aft packaging unit containing radwaste was transported to the storage facility in Saida Bay. The used fuel still stored on the vessel has a total activity of more than 680,000 curies.
Now, the final stage of the project will begin and the bow section will be brought inside the shelter where the used fuel will be extracted using special remotely controlled equipment. The unloading and disposal operations will first be tested out using a simulator. Unloading of the fuel is scheduled for the first quarter of 2019 with the aim of completing the process by 2020.
Oleg Kryukov , Director for State Policy in the Nuclear and Radiation Safety at state nuclear corporation Rosatom said security was the main concern. “Last year, we began to transport used fuel from the storage facility in Andreeva Bay, and over 3,000 assemblies have already been sent for processing. Now it's time to unload fuel from Lepse."he said.
The EBRD said €23m shelter was financed through the Nuclear Window of the Northern Dimension Environmental Partnership Support Fund, an international fund with contributions from Belgium, Canada, Denmark, the European Union, Finland, France, Germany, the Netherlands, Norway and the UK, and managed by the EBRD.
Photo: Lepse (Source: EBRD)