First fuel assemblies leave the Lepse, Russia’s most hazardous nuclear ship

lepse header. (Photo: Thomas Nilsen) The Lepse. Credit: Thomas Nilsen

The first containers of nuclear fuel have been removed from the Lepse service ship, Russia’s waterborne atomic graveyard, marking a major step in an international radiation safety project that has spanned decades.

The vessel, which technicians are carefully pulling apart at the Nerpa Shipyard near Murmansk, spent years refueling Russia’s nuclear icebreaker at the Atomflot icebreaker port – a job that transformed it into one of the world’s most dangerous radioactive hazards. Ever since its retirement, the Lepse has been a worrying chapter in Northwest Russia’s legacy of Cold War nuclear waste.

Removing spent fuel from the vessel – including the extraction of several damaged assemblies – is among the most challenging nuclear cleanup operations that Russia has ever undertaken. When it’s finally complete next year, it will represent the years-long culmination of high-tech preparation and millions of dollars from Western donors, given in often trying political circumstances.

This new phase in the Lepse’s dismantlement marks another milestone in the overall cleanup of naval and civilian nuclear debris in Northwest Russia – an effort that has been ongoing since the fall of the Soviet Union in 1991. Since 2017, containers of spent nuclear submarine fuel that accrued over five decades at nearby Andreyeva Bay have been making their way to safer storage. Both are projects that Bellona has long advocated for.

Last Friday, the European Bank of Reconstruction and Development announced that the first spent fuel shipment, consisting of 111 fuel assemblies spread across six casks, had left the Lepse for the Atomflot nuclear icebreaker port in Murmansk.

Five more shipments, carried aboard the Sererbyanka nuclear service ship, will follow by the mid-2020s, completing the process. The fuel assemblies will then make their way from Atomflot by rail to the Mayak Production Association, Russia’s main nuclear fuel reprocessing facility.

During its career, the Lepse amassed 639 fuel assemblies in its holds, many from refueling the Lenin, the Soviet Union’s flagship icebreaker, between the year of 1965 and 1967. Many of those fuel rods were warped and damaged after the Lenin suffered a reactor accident. Other fuel rods from the Sibir icebreaker had to be pounded into the Lepse’s fuel storage channels with hammers.

The $58 million project to extract the fuel – financed by the EBRD’s Northern Dimensions Environmental fund – has been years in the making and uses technology that had to be developed along the way.

lepse shelter Part of the enormous shelter in which the Lepse's spent nuclear fuel assemblies are being extracted. Credit: Bellona

Robotic arms were designed to remove the most dangerous fuel elements from the Lepse’s holds, and the rest of the cleanup effort is staffed by thousands of technicians working from a small city of radiation shelters that surround the vessel’s hull.

Vycheslav Ruksha, one of the first high-ranking Russian officials to recognize the dangers posed by the Lepse, said in a statement that the fuel removal hit close to home.

“For me, the implementation of the international project for the disposal of the Lepse is an extremely important and personal matter,” said Rukhsa, who, as the then-head of Atomflot, joined Bellona’s early efforts to publicize the Lepse quandary. Ruksha now heads the Northern Sea Route Directorate for Rosatom, Russia’s state nuclear corporation. He added that the Lepse mission “is the most important event in the ecological rehabilitation of the region and in the lives of everyone who participated in this project.”

The Lepse came into service well before the atomic age. Built in 1934 as a Ukrainian dry goods freighter, the vessel was press-ganged into nuclear service in 1961. In 1988, it was retired and moored at Atomflot, where it sat for more than 20 years, laden with its radioactive cargo just four kilometers from central Murmansk and it’s population of 300,000.

The Lepse was finally towed from Atomflot to the Nerpa naval shipyard in September 2012, after more than a decade of strenuous negotiations among Bellona, the Russian government and the EBRD to mobilize funding for its safe disposal.

After the Lepse was finally put into dry-dock at Nerpa, it was cut into sections, or what technicians refer to as “storage packages.” These packages comprise five sections of the vessel: the stern section, which is said to be relatively uncontaminated; the section with liquid radioactive waste tanks; the engine and boiler room, and two packaged bow sections, one of which contains the notorious 639 spent nuclear fuel assemblies.

When the vessel was hauled out of the water onto a special slipway, the bow storage package, along with the side sections, were completely enclosed to ensure climate control for the spent nuclear fuel assemblies inside.

The vessel was also fitted with a communications system, a ventilation system and trace gas detection equipment to ensure safety for the 5,000 technicians who worked on its dismantlement. That number has dramatically reduced to a few dozen as the project nears completion.

It was in 1994 that the vessel and the dangers it posed to Murmansk caught Bellona’s eye, and the organization mobilized the European Union to allocate funding toward removing it from the city’s harbor and safely dismantling it.

When it was finally towed to Nerpa, the Lepse ran into further complications. Rosatom and the Ministry of Defense were locked in a quarrel about what to do with the Leninsky Komsomol nuclear submarine – the Soviet Union’s first – which was taking up the Lepse’s berth.

Those difficulties were finally resolved and the Lepse was gingerly moved from the water to dry dock. The Leninsky Komsomol, which had already been cut into three pieces, was welded back together as a museum piece.

Charles Digges

charles@bellona.no