Rosatom has completed the disposal of the Lepse floating base with nuclear waste
MOSCOW, Nov 22 - RIA Novosti. Rosatom State Corporation has completed a large project in the North-West of the Russian Federation that lasted for over 10 years to ensure the environmental safety of the nuclear industry - the disposal of the Lepse floating technical base (PTB), which provided the operation of the first nuclear icebreakers and whose storage of spent nuclear fuel (SNF) for many years posed a significant environmental risk to the region, has been completed.
"In its place in the storage of reactor compartments located in Saida Bay, the last, bow, block-packing with deactivated fragments of the vessel has taken its place," Rosatom said in a statement.
The main source of radioactive danger of the Lepse PTB was its storage of spent nuclear fuel. The work on unloading and exporting 639 fuel assemblies from the floating base outside the region, some of which were damaged (which means that they could not be removed from the ship by conventional means), required special technical solutions from nuclear industry specialists.
In particular, for unloading spent nuclear fuel, Lepse was placed in a specially designed and constructed ground-based shelter. This made it possible to exclude the influence of weather - sea waves and precipitation. The technology of unloading fuel together with the shell of storage cells was invented in order to prevent the fuel assemblies from collapsing during unloading. To do this, it was necessary to design and manufacture a special tool and equipment. The work was carried out using a robotic remotely controlled complex.
"The State Corporation undertakes the solution of the most difficult environmental tasks: we are engaged in the elimination of the nuclear legacy and the legacy of toxic industrial production, we are creating an infrastructure in the country for the management of radiation and chemical waste," said Andrey Nikipelov, Deputy Director General of Rosatom for Mechanical Engineering and Industrial Solutions, who spoke at a solemn event dedicated to the completion of the project.
Russian nuclear scientists have been systematically cleaning the Arctic and Far East coasts from radiation-hazardous objects for more than 20 years, disposing of decommissioned nuclear submarines and support vessels, he noted.
"And in this sense, today is a special day for us: one of the landmark environmental projects of the state corporation - the liquidation of the Lepse floating base - has been completed. There is one less dangerous object in the Arctic," Nikipelov added.
Various organizations of the nuclear industry and enterprises of the North-Western region took part in the implementation of the project. Now the fragments of the vessel no longer pose a danger, additional biological protection is installed on them from the outside, which will ensure safety during long-term storage. In the Murmansk Region, spent nuclear fuel is being exported as planned. From 2002 to 2023, the total volume of accumulated SNF decreased by half. The remaining SNF is being removed from the storage in Gremikha - completion of all work is expected in 2025. More than half of the spent fuel has already been removed from the facility in Andreev Bay, and the removal work is planned to be completed by 2028.
Rosatom continues to clean the waters of the Arctic and the Far East from radiation-hazardous objects. To date, 202 nuclear submarines that have been decommissioned have been disposed of in the country. All accumulated spent nuclear fuel has been removed from the Far East, the state corporation notes.
History of the floating base
The vessel "Lepse" was built in 1934 at the Nikolaev shipyards as a regular transport - a timber carrier (dry cargo). However, it was never used for its intended purpose. During the Great Patriotic War, the steamer had to be flooded when the Nazis attacked. They tried to restore the ship after the war, but then it was handed over to Leningrad shipbuilders, who in 1961 completed it in a different capacity - as a floating technical base for servicing the USSR nuclear fleet. The vessel was equipped with a storage facility for spent nuclear fuel, tanks for the collection and temporary storage of liquid radioactive waste and production facilities for carrying out technological operations with reactor equipment. So "Lepse" turned out to be in the Murmansk shipping company.
From 1964 to 1988, the Lepse PTB not only serviced the nuclear power plants of the nuclear icebreakers Lenin, Arctic and Siberia, but also carried out flights with radioactive cargo to their burial sites in the Barents and Kara Seas. Since 1981, the "Lepse" was replaced by the "Imandra" floating base. The vessel "Lepse" was then used only for temporary storage of radioactive waste, and in 1988 it was decommissioned, in 1990 it was anchored in the Murmansk region.
Storage of spent nuclear fuel at Leps was carried out in the so-called "wet" mode, when the pencil cases were filled with water. As a result of long-term storage of fuel assemblies in water, their corrosion destruction occurred. In 1991, in order to create an additional engineering barrier, the inter-tank space of the SNF storage at Leps was filled with special concrete mixtures. The survey of the vessel and the development of the disposal project began in 2005. In 2012, the radiation and engineering survey of the vessel and its storage was completed, the vessel was towed to the Nerpa ship repair plant for subsequent disposal.
From 2012 to 2017, the Lepse floating base was gradually dismantled, this scrap metal was disposed of. SNF was exported for processing to the Rosatom enterprise "Mayak Production Association" (BUT Ozersk, Chelyabinsk region). In April 2022, the last batch of spent fuel went there.