Tag Archives: Onkalo radioactive storage site

Bury It and Forget It: Nuclear Waste

The first nuclear burial site has been built in Finland, the Onkalo spent nuclear fuel repository]. Deep geological disposal of this sort is widely held to be the safest way to deal with the more than 260,000 tons of spent nuclear fuel which has accumulated in 33 countries since the first nuclear plants began churning out electricity in the mid-1950s, and the still large…. Spent fuel is a high-level nuclear waste. That means it is both physically hot (because of the energy released by radioactive decay) and metaphorically so—producing radiation of such intensity that it will kill a human being in short order. Yet unlike the most radioactive substances of all, which necessarily have short half-lives, spent fuel will remain hot for hundreds of thousands of years—as long, in fact, as Homo sapiens has walked Earth—before its radioactivity returns to roughly the same level as that of the ore it came from.

Once full, the waste repository will be backfilled with bentonite before their entrances are sealed with a reinforced-concrete cap. In 100 years’ time, Finland will fill the whole site in, remove all traces of buildings from the surface and hand responsibility over to the Finnish government. The thinking is that leaving no trace or indication of what lies below is preferable to signposting the repository for the curious to investigate.

[Unless someone decides to drill?]

Excerpt from Nuclear Waste: Oubliette, Economist, June 25, 2022

Taking Pride in Nuclear Waste: Finland and Sweden

The site for Posiva’s repository at Eurajoki for the disposal of Finland’s high-level radioactive waste (used nuclear fuel), near the Olkiluoto nuclear power plant, was selected in 2000. The Finnish parliament approved the the repository project the following year in 2001… The government granted a construction licence for the project in November 2015 and construction work on the repository started iin 2016.  Posiva’s plan is for used nuclear fuel to be packed inside copper-steel canisters at an above-ground encapsulation plant, from where they will be transferred into the underground tunnels of the repository, located at a depth of 400-450 meters, and further into deposition holes lined with a bentonite buffer. Operation of the repository is expected to begin in 2023. The cost estimate of this large-scale construction project totals about EUR500 million (USD570 million), the company said.

Posiva  announced on June 25, 2019  the start of construction of the used fuel encapsulation plant. Janne Mokka, Posiva’s President, noted, “In Finland, full lifecycle management of nuclear fuel is a precondition for the production of climate-friendly nuclear electricity. Posiva will execute the final disposal of the spent fuel of its owners’ Olkiluoto and Loviisa nuclear power plants responsibly.”

Sweden is planning a similar used fuel encapsulation and disposal facility using the same storage method. Under its current timetable, national radioactive waste management company Svensk Kärnbränslehantering AB plans to start construction of the used fuel repository and the encapsulation plant sometime early in the 2020s and they will take about 10 years to complete.

Exceprts from Work starts on Finnish fuel encapsulation plant, World Nuclear News, June 25, 2019

See also documentary “Into Eternity” (YouTube)

Nuclear Priesthood: the future of nuclear waste

As  the world increasingly buries its nuclear waste, a growing number of experts are trying to come up with a way to warn future generations of what, exactly, will be lying under their feet.    Deciding where to create nuclear waste storage sites, demarcating them clearly and then writing it all down seems like the obvious solution. After all, mankind started writing down its history 5,500 years ago and the likelihood of us stopping to do so seems slim.   But the question then becomes: what should we write this crucial piece of information on?  Stone and paper deteriorate. USB sticks and servers do, too.  Some government entities, like ANDRA, the French National Agency in charge of managing radioactive waste, have started to record their archive on permanent paper.  Also known as acid-free paper due to its composition, it can remain chemically and physically stable for a long period of time — unlike traditional paper, which starts to yellow and decay over time when exposed to light or heat.

The agency has also built sapphire discs, made out of sapphire and etched with platinum on one side. These can contain up to 40,000 pages of pictures and text and could, theoretically, last for some two million years.   Language, after all, is a living, changing entity. That’s why it took us decades to decode Egyptian hieroglyphs and why you might have gotten a headache reading Shakespeare’s Old English masterpieces in class. So who’s to say that French scientists 1,000 years from now will be able to understand la langue de Moliere’s current form?  The OECD’s Nuclear Energy Agency (NEA) has since created a working group whose task it is to set the best practices on Radioactive Waste Repository Metadata Management so that all the information is not only stored properly but is also easily accessible as national nuclear waste programmes evolve…

In a report, the researchers led by Thomas Sebeok of the University of Indiana recommended the creation of a nuclear priesthood, inspired by the Catholic Church, which would relay information down the generations through “a mixture of iconic, indexical and symbolic elements” and “a high degree of redundancy of messages.”..

The problem with art, explained Peter Galison, professor of the History of Science and of Physics at Harvard University and author of the Containment documentary, is that if a message is too artistic, then it might not be properly understood as different people may have different interpretations of it….For instance, you know for sure what the skull pictogram means. If you’re thinking death, you’re right. Yet this symbol, Blanquer said, “comes from alchemists.”  “The skull represents Adam and the crossing bones the promise of resurrection,” he revealed. So in the span of just a few centuries this particular pictogram has evolved from meaning resurrection to meaning death.

As waste can be buried either near or deep under the surface, the signal should be seen both above but also under the ground. The researchers employed by the US Department of Energy in the mid-1980s (who came up with the nuclear priesthood, remember!), had also envisioned different monuments to get the point across: fields of pikes, threatening statues of thunderbolts, or enormous blocs of granite positioned into a tight grid….
The Finnish project of Onkalo took the problem completely differently: what if we came up with a way that would allow us to simply not tell future generations?  Its solution? Digging a deep geological repository for spent nuclear fuel.  “The entire concept of Posiva (the company which manages the project), is that 100 to 120 years after it’s been closed, the site will not be signalled. The 500 meters to the storage site in the geological layer will be filled with rock and the entire thing will be isolated and invisible in the natural landscape.”

Excerpts from What will a nuclear waste warning look like in 100,000 years’ time?, Euronews, Nov. 16, 2018