How do you dismantle a nuclear submarine?
By Paul Marks
(Credit: AFP/Getty Images)
When nuclear-powered submarines reach the end of their lives, dismantling them is a
complicated and laborious process. Paul Marks investigates.
Nuclear submarines have long been a favourite in popular fiction. From movies such as The Hunt
for Red October to long-running TV series like Voyage to the Bottom of the Sea, they have
always been portrayed as awesome instruments of geopolitical power gliding quietly through the
gloomy deep on secret, serious missions.
An aquarium of radioactive junk — The Kara Sea, a
submarine graveyard
But at the end of their useful lives the subs essentially become floating nuclear hazards, fizzing
with lethal, spent nuclear fuel that's extremely hard to get out. Nuclear navies have had to go to
extraordinary lengths to cope with their bloated and ageing Cold War fleets of hunter-killer and
ballistic missile nuclear subs.
(
Credit: Science Photo Library)
As a result, some of the strangest industrial graveyards on the planet have been created –
stretching from the US Pacific Northwest, via the Arctic Circle to Russia’s Pacific Fleet home of
Vladivostok.
When nuclear-powered submarines reach the end of their lives, dismantling them is a
complicated and laborious process. Paul Marks investigates.
Nuclear submarines have long been a favourite in popular fiction. From movies such as The Hunt
for Red October to long-running TV series like Voyage to the Bottom of the Sea, they have
always been portrayed as awesome instruments of geopolitical power gliding quietly through the
gloomy deep on secret, serious missions.
But at the end of their useful lives the subs essentially become floating nuclear hazards, fizzing
with lethal, spent nuclear fuel that's extremely hard to get out. Nuclear navies have had to go to
extraordinary lengths to cope with their bloated and ageing Cold War fleets of hunter-killer and
ballistic missile nuclear subs.
These submarine cemeteries take many forms. At the filthy end of the spectrum, in the Kara Sea
north of Siberia, they are essentially nuclear dumping grounds, with submarine reactors and fuel
strewn across the 300m-deep seabed. Here the Russians appear to have continued, until the
early 1990s, disposing of their nuclear subs in the same manner as their diesel-powered
compatriots: dropping them into the ocean.
Rusting remains
The diesel sub scrapyard in the inlets around Olenya Bay in north-west Russia's arctic Kola
Peninsula is an arresting sight: rusted-through prows expose torpedo tubes inside, corroded
conning towers keel over at bizarre angles and hulls are burst asunder, like mussels smashed on
rocks by gulls.
The Soviets turned the Kara Sea into "an aquarium of radioactive junk" says Norway’s Bellona
Foundation, an environmental watchdog based in Oslo. The seabed is littered with some 17,000
naval radioactive waste containers, 16 nuclear reactors and five complete nuclear submarines –
one has both its reactors still fully fuelled.
Russian reactors have been stored in the harbour at Vladivostok (Credit: Bellona Foundation)
The Kara Sea area is now a target for oil and gas companies – and accidental drilling into such
waste could, in principle, breach reactor containments or fuel rod cladding, and release
radionuclides into the fishing grounds, warns Bellona's managing director Nils Bohmer.
Official submarine graveyards are much more visible: you can even see them on Google Maps or
Google Earth. Zoom in on America's biggest nuclear waste repository in Hanford, Washington,
Sayda Bay in the arctic Kola Peninsula, or the shipyards near Vladivostok and you'll see them.
There are row after row of massive steel canisters, each around 12m long. They are lined up in
ranks in Hanford's long, earthen pits awaiting a future mass burial, sitting in regimented rows on a
Sayda Bay dockside, or floating on the waters of the Sea of Japan, shackled to a pier at the
Pavlovks sub base near Vladivostok.
Drained and removed
These canisters are all that remain of hundreds of nuclear subs. Known as "three-compartment
units" they are the sealed, de-fuelled reactor blocks produced in a decommissioning process
perfected at the US Department of Defense's Puget Sound Naval Shipyard in Bremerton,
Washington.
It’s a meticulous process. First, the defunct sub is towed to a secure de-fuelling dock where its
reactor compartment is drained of all liquids to expose its spent nuclear fuel assemblies. Each
assembly is then removed and placed in spent nuclear fuel casks and put on secure trains for
disposal at a long-term waste storage and reprocessing plant. In the US, this is the Naval Reactor
Facility at the sprawling Idaho National Laboratory, and in Russia the Mayak plutonium
production and reprocessing plant in Siberia is the final destination.
(Credit: Getty Images)
Although the reactor machinery – steam generators, pumps, valves and piping – now contains no
enriched uranium, the metals in it are rendered radioactive by decades of neutron bombardment
shredding their atoms. So after fuel removal, the sub is towed into dry dock where cutting tools
and blowtorches are used to sever the reactor compartment, plus an emptied compartment either
side of it, from the submarine's hull. Then thick steel seals are welded to either end. So the
canisters are not merely receptacles: they are giant high-pressure steel segments of the nuclear
submarine itself – all that remains of it, in fact, as all nonradioactive submarine sections are then
recycled.
Russia also uses this technique because the West feared that its less rigorous decommissioning
processes risked fissile materials getting into unfriendly hands. At Andreeva Bay, near Sayda, for
instance, Russia still stores spent fuel from 90 subs from the 1960s and 1970s, for instance. So in
2002, the G8 nations started a 10-year, $20bn programme to transfer Puget Sound's
decommissioning knowhow to the Russian Federation. That involved vastly improving technology
and storage at their de-fuelling facility in Severodvinsk and their dismantling facility, and by
building a land-based storage dock for the decommissioned reactors.
Floating menace
When nuclear-powered submarines reach the end of their lives, dismantling them is a
complicated and laborious process. Paul Marks investigates.
The secrets written in your face
Nuclear submarines have long been a favourite in popular fiction. From movies such as The Hunt
for Red October to long-running TV series like Voyage to the Bottom of the Sea, they have
always been portrayed as awesome instruments of geopolitical power gliding quietly through the
gloomy deep on secret, serious missions.
As a result, some of the strangest industrial graveyards on the planet have been created –
stretching from the US Pacific Northwest, via the Arctic Circle to Russia’s Pacific Fleet home of
Vladivostok.
These submarine cemeteries take many forms. At the filthy end of the spectrum, in the Kara Sea
north of Siberia, they are essentially nuclear dumping grounds, with submarine reactors and fuel
strewn across the 300m-deep seabed. Here the Russians appear to have continued, until the
early 1990s, disposing of their nuclear subs in the same manner as their diesel-powered
compatriots: dropping them into the ocean.
Rusting remains
The diesel sub scrapyard in the inlets around Olenya Bay in north-west Russia's arctic Kola
Peninsula is an arresting sight: rusted-through prows expose torpedo tubes inside, corroded
conning towers keel over at bizarre angles and hulls are burst asunder, like mussels smashed on
rocks by gulls.
The Soviets turned the Kara Sea into "an aquarium of radioactive junk" says Norway’s Bellona
Foundation, an environmental watchdog based in Oslo. The seabed is littered with some 17,000
naval radioactive waste containers, 16 nuclear reactors and five complete nuclear submarines –
one has both its reactors still fully fuelled.
Russian reactors have been stored in the harbour at Vladivostok (Credit: Bellona Foundation)
The Kara Sea area is now a target for oil and gas companies – and accidental drilling into such
waste could, in principle, breach reactor containments or fuel rod cladding, and release
radionuclides into the fishing grounds, warns Bellona's managing director Nils Bohmer.
Official submarine graveyards are much more visible: you can even see them on Google Maps or
Google Earth. Zoom in on America's biggest nuclear waste repository in Hanford, Washington,
Sayda Bay in the arctic Kola Peninsula, or the shipyards near Vladivostok and you'll see them.
There are row after row of massive steel canisters, each around 12m long. They are lined up in
ranks in Hanford's long, earthen pits awaiting a future mass burial, sitting in regimented rows on a
Sayda Bay dockside, or floating on the waters of the Sea of Japan, shackled to a pier at the
Pavlovks sub base near Vladivostok.
Drained and removed
These canisters are all that remain of hundreds of nuclear subs. Known as "three-compartment
units" they are the sealed, de-fuelled reactor blocks produced in a decommissioning process
perfected at the US Department of Defense's Puget Sound Naval Shipyard in Bremerton,
Washington.
It’s a meticulous process. First, the defunct sub is towed to a secure de-fuelling dock where its
reactor compartment is drained of all liquids to expose its spent nuclear fuel assemblies. Each
assembly is then removed and placed in spent nuclear fuel casks and put on secure trains for
disposal at a long-term waste storage and reprocessing plant. In the US, this is the Naval Reactor
Facility at the sprawling Idaho National Laboratory, and in Russia the Mayak plutonium
production and reprocessing plant in Siberia is the final destination.
Although the reactor machinery – steam generators, pumps, valves and piping – now contains no
enriched uranium, the metals in it are rendered radioactive by decades of neutron bombardment
shredding their atoms. So after fuel removal, the sub is towed into dry dock where cutting tools
and blowtorches are used to sever the reactor compartment, plus an emptied compartment either
side of it, from the submarine's hull. Then thick steel seals are welded to either end. So the
canisters are not merely receptacles: they are giant high-pressure steel segments of the nuclear
submarine itself – all that remains of it, in fact, as all nonradioactive submarine sections are then
recycled.
Russia also uses this technique because the West feared that its less rigorous decommissioning
processes risked fissile materials getting into unfriendly hands. At Andreeva Bay, near Sayda, for
instance, Russia still stores spent fuel from 90 subs from the 1960s and 1970s, for instance. So in
2002, the G8 nations started a 10-year, $20bn programme to transfer Puget Sound's
decommissioning knowhow to the Russian Federation. That involved vastly improving technology
and storage at their de-fuelling facility in Severodvinsk and their dismantling facility, and by
building a land-based storage dock for the decommissioned reactors.
Floating menace
Safer land-based storage matters because the reactor blocks had been left afloat at Sayda Bay,
as the air-filled compartments either side of the reactor compartment provide buoyancy, says
Bohmer. But at Pavlovks, near Vladivostok, 54 of the canisters are still afloat and at the mercy of
the weather.
Decommissioning this way is not always possible, however, says Bohmer. Some Soviet subs had
liquid metal cooled reactors – using a lead-bismuth mixture to remove heat from the core – rather
than the common pressurised water reactor (PWR). In a cold, defunct reactor the lead-bismuth
coolant freezes, turning it into an unwieldy solid block. Bohmer says two such submarines are not
yet decommissioned and have had to be moved to an extremely remote dockyard at Gremikha
Bay – also on the Kola Peninsula – for safety's sake.
When nuclear submarines reach the end of their lives, some of their hulks remain dangerously
radioactive (Credit: Science Photo Library)
Using the three-compartment-unit method, Russia has so far decommissioned 120 nuclear
submarines of the Northern Fleet and 75 subs from its Pacific Fleet. In the US, meanwhile, 125
Cold War-era subs have been dismantled this way. France, too, has used the same procedure. In
Britain, however, Royal Navy nuclear subs are designed so that the reactor module can be
removed without having to sever compartments from the midsection. "The reactor pressure
vessel can be removed in one piece, encased, transported and stored," says a spokesman for
the UK Ministry of Defence.
However Britain's plans to decommission 12 defunct submarines stored at Devonport in the south
of England and seven at Rosyth in Scotland won't happen any time soon as the government still
has to decide which of five possible UK sites will eventually store those pressure vessels and
spent fuel. This has raised community concerns as the numbers of defunct nuclear-fuelled subs is
building up at Devonport and Rosyth, as BBC News reported last year.
Water fears
Environmental groups have also raised concerns about fuel storage in the US. The Idaho
National Lab has been the ultimate destination for all US Navy high-level spent fuel since the first
nuclear sub, USS Nautilus, was developed in 1953. "The prototype reactor for the USS Nautilus
was tested at INL and since then every scrap of spent fuel from the nuclear navy has ended up in
Idaho. It is stored above the upstream end of the Snake River Aquifer, the second largest unified
underground body of water on the North American continent," says Beatrice Brailsford of the
Snake River Alliance, an environmental lobby group.
"The spent fuel is stored above ground, but the rest of the waste is buried above the aquifer and
that practice may continue for another half century. It is a source of concern for many people in
Idaho." It's not only the aquifer's fresh water that's at risk: the state’s signature crop, potatoes,
would also be affected.
Even with high security, radioactive material can occasionally escape – sometimes in bizarre
ways. For instance both INL and Hanford have suffered unusual radiation leaks from
tumbleweeds blowing into waste cooling ponds, picking up contaminated water, and then being
blown over the facility's perimeter by the wind.
The expensive, long-term measures that have to be taken to render a defunct nuclear sub safe
don’t seem to deter military planners from building more vessels. "As far as the US is concerned
there is no indication that the Navy believes nuclear submarines have been anything less than a
stellar success and replacements for the major submarine classes are in the works." says Edwin
Lyman, nuclear policy analyst at the Union of Concerned Scientists, a pressure group, in
Cambridge, Massachusetts.
The US is not alone: Russia has four new nuclear subs under construction at Severodvinsk and
may build a further eight before 2020. "Despite limited budgets Russia is committed to building up
its nuclear fleet again," says Bohmer. China is doing likewise.
The submarine graveyards and spent fuel stores, it appears, will continue to be busy.