Can a guide to Sweden's repository last 100,000 years?

Thursday, 20 March 2025

Sweden's radioactive waste management company Svensk Kärnbränslehantering AB (SKB) submitted applications to build Sweden's first nuclear fuel repository and an encapsulation plant to SSM in March 2011. In January 2022, Sweden's Minister of Climate and Environment announced that construction of the final repository for used nuclear fuel in Forsmark and the associated fuel encapsulation plant in Oskarshamn can proceed. The repository is designed to last 100,000 years, which is how long planners say that it will take the fuel to return to a level of radioactivity comparable with uranium found in the earth's bedrock.

Although the repository is to be sealed and should in theory be inaccessible, accidental or intentional intrusion, technological failure or existential societal change cannot be ruled out. All of this makes it important not to forget what is buried there.

The Linköping University researchers have now come up with a proposal for keeping the memory of the final repository alive over generations. Through work partly supported by SKB, they have produced a 42-page document that contains the most important information that a future reader may need about the planned final repository. Currently only available in English, it is divided into three parts: summary, critical information and instructions for the future. To ensure its durability and survival through time, the plan is for it to be reproduced in different media formats and translated into multiple languages.

The researchers have tried to create a document enticing the reader to re-read it and share it with others. They have used professional illustrators to make it aesthetically pleasing. While the text is easy to understand, there are mysterious characters on the cover. It is a coded message for the reader to try to solve. Through playfulness, the researchers want to create curiosity and enthusiasm.

"Language changes over time. So does the interpretation of images and symbols," the university noted. "The document therefore tasks future generations with updating the information and transferring it to new storage media if necessary. It also provides suggestions on how knowledge can be kept alive, for example by including it as a subject in school curricula or creating stories and other cultural expressions around it."

The researchers have named this method SHIRE (Share, Imagine, Renew). It is an invitation to the reader to share the content and become actively involved in figuring out how it can be renewed so as not to be forgotten.

The Key Information File is the result of three years of work in which the researchers have collected opinions from many sources, from young and old, experts and the general public. It is part of a major international initiative, in which several countries, such as France and Switzerland, are working on similar documents for their final repositories.

The idea now is that the document be kept at the Swedish National Archives in Stockholm. In addition, it has already been decided that it will be part of the major archiving project Memory of Mankind. It is an archive founded in Austria in 2012 which aims to preserve humanity’s collective knowledge for posterity on material that will last for thousands of years.

The researchers propose an update of the document every ten years, but it is not clear who will be responsible for this in Sweden. Although SKB has financed the research project, it has stated that it does not have formal responsibility but is willing to contribute in some form.

"We're trying to do something that no one has ever done before," said postdoctoral fellow Thomas Keating, who led the research project together with Professor Anna Storm at Tema T – Technology and Social Change at the university. "The person who eventually reads this might not even be human, but perhaps a kind of AI or something else.

"Perhaps we need a whole new research area for this type of memory study. This could be something for universities to develop in the future."

In 2011, the OECD Nuclear Energy Agency initiated the Preservation of Records, Knowledge and Memory Across Generations (RK&M) project. The purpose of that project was partly to develop the theoretical basis, and partly to develop concrete proposals, for information and knowledge preservation further into the future.

The main recommendation from the RK&M project, which ended in 2018, was that the preservation of information and knowledge should apply a so-called systemic strategy. This, the final report said, will involve using different methods, media and content, across different time scales with several actors and places. Nine categories of methods were developed: final repository documentation; memorial institutions; markers; time capsules; culture, education and art; knowledge management; oversight provisions; international mechanisms; and the legal basis.