A nuclear waste storage facility deep in the bedrock below Finland is the subject of a feature-length documentary called Into Eternity.

Around the world, nuclear power plants are churning out high-level radioactive waste at a rate of knots. It's estimated that about 250,000 tonnes of the material is currently in interim storage, submerged in huge tanks of water in facilities that keep it safe -- temporarily.

But there's very little agreement on what to do with the stuff long-term, as it will remain a danger for around 100,000 years -- almost as long as humans have existed, and far longer than we've been using tools. There have been a few proposals, including the possibility of loading it into a rocket and shooting it into the Sun, or sinking it to the bottom of the sea. But the most likely seems to be storage in deep geological repositories.


There are 10 or so of these repositories bored into the bedrock around the world, in the USA, Switzerland, Sweden, Japan, France, Canada, Belgium and Finland. Finnish law dictates that all nuclear waste produced in the country must be disposed of in the country too, so the government is constructing a facility called Onkalo, located near the Olkiluoto nuclear power plant.

Onkalo consists of a massive warren of underground tunnels, half a kilometre below the Earth's surface, which is expected to be completed in 2020. It will be progressively filled with waste over a period of about 100 years until 2120, when it'll be backfilled and sealed for the next 100,000 years.

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It's also the subject of a feature-length documentary called Into Eternity, from a Danish director named Michael Madsen. Into Eternity is an intriguing, unsettling and thought-provoking look at the project, with in-depth interviews with a number of key figures involved in the project, such as Timo Äikäs, Onkalo's executive vice-president of engineering; Wandla Paile, the chief radiologist at Finland's radiation and nuclear safety authority; and Carl Reinhold Bråkenhielm, a member of Sweden's national council for nuclear waste.

The cinematography is superb, and those who enjoy seeing inside post-industrial structures are in for a treat. There's plenty of footage of existing temporary storage sites, with spent fuel being loaded into tubes underwater. There's also lots of camera-time for the tunnel itself, the blasting process, and the dormitories where the workers blasting their way through the rock live.


One theme running throughout the 75-minute documentary is that of how to get our children's children's children's children to stay away. If the human race survives for another 100,000 years, it's unlikely to remain in the same state, and if we're having trouble reading the hieroglyphics of the Egyptians from just 3,000 years ago, the odds of our descendants being able to understand any warnings we leave are low.

Even leaving aside language barriers, there's a big question mark over whether future generations will have the knowledge to understand nuclear waste's silent but deadly threat. The dark ages following the decline of the Roman Empire may well be repeated in the future, and there's no guarantee that our descendants will be able to comprehend what radiation is.

As a result, there's a divide in the documentary between those who believe that it's best to leave warnings, and those who believe that it should go unmarked and forgotten. Proponents of the latter approach argue that any signs on the surface will foster humanity's insatiable curiosity, but those who favour warning signs argue that there's a good chance of it being found anyway, so it's better to give some indication that it might not be a good idea to go down there.

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Despite the documentary's rather weighty subject matter, there's humour. At one point, one of the interviewees wonders out loud whether they'll get to the bottom and break into a cavern containing hundreds of canisters of nuclear waste from a prior civilisation that had gone hitherto undiscovered.


But one particularly chilling moment occurs near the end of the documentary, when all the people interviewed are asked to send a message to anyone who might find the facility in the future. Each stares into the camera for a few moments, trying to reconcile in their head exactly what that future might entail, and then intones a warning to turn around, go back where they came, and never, ever, enter Onkalo.

Into Eternity will be arriving in cinemas across Britain at the end of October. The trailer is embedded below, and we've put together a delightful photo gallery for your perusal too. Go check it out.

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