On the 16th of October 2025 ICCROM organized a workshop on Strategic Foresight in Heritage taking place in Rome, titled Anticipating Change: Exploring Long-term Futures for Heritage. The purpose of the workshop was to found a community for practice surrounding Strategic Foresight in heritage, to build resilience, relevance and agency among heritage organisations in the face of uncertainty and change.
Gustav Wollentz from the UNESCO Chair on Heritage Futures assisted in the organisation and facilitation of the workshop, contributing with a presentation on the value of Strategic Foresight in heritage and moderating parts of the agenda, which included both a hands-on Foresight exercise, the Futures Wheel, as well as a discussion on how to move forward together.
The goals of the newly established group are to:
Connect and amplify foresight and innovation efforts across the heritage sector.
Co-developing and testing foresight methods in real-world heritage contexts.
Building an open repository of trends, tools, and insights tailored to the sector’s needs.
Together vid ICCROM, the workshop gathered representatives from the International Council on Archives, ICOM (International Council of Museums), IFLA (International Federation of Library Associations and Institutions), NEMO (Network of European Museum Organizations), UNESCO, the French Ministry of Culture, the Swedish National Heritage Board, the Heritage Alliance, UK, the Fondation des Sciences du Patrimoine, France, the Getty Foundation, USA, and University College London, UK.
On Wednesday, 22 October, Anders Högberg was invited by the Norwegian National Heritage Board (Riksantikvaren) to give a presentation on Heritage Practices as Futures-Making Practices. The presentation was well received, and the subsequent discussion centred largely on the novelty of the future-oriented perspective that was introduced, as well as on how one might think in order to translate future-oriented ideas into more concrete heritage practices.
Anders Högberg, professor of Archaeology and member of the UNESCO Chair on Heritage Futures at Linnaeus University.
Claudio Pescatore explains why high-level waste still needs shields—and memory beyond a million years:
When it comes to high-level waste repositories, the old reassurance — “radioactivity falls back close to or below natural levels” — is misleading. Yes, if you total up all the radioactivity in a repository and compare it to the original ore, the sum may look modest after ten to a hundred thousand years, depending on waste type. But people (and animals) don’t meet sums. They meet things: individual containers, cores, and fragments that concentrate radioactivity. What matters—ethically and practically—is the radiation dose at the surface of each piece as time rolls on.
Total radioactivity vs original uranium ore in Swedish spent fuel. (Report SKB-TR-97-13)
A new paper looks squarely at that reality. Rather than only computing dose, a concept for radiation specialists, it asks a tangible question: how thick must a shield be to meet modern radiation protection limit not just now, but at one million years and beyond? Using concrete as the reference, the answer comes in units anyone can picture: roughly 50–90 cmat a million years, depending on the waste and the protection target.
At one million years (and ignoring any container):
Spent fuel (SF) requires about 67–93 cm of concrete for a representative multi-ton package
Vitrified high-level waste(VHLW) requires about 53–72 cm of concrete for a full-size cylinder.
Beyond one million years, uranium-238 — lasting billions of years — makes the shielding requirement essentially constant: without containers, concrete thicknesses range from 7–42 cm for vitrified-waste cylinders and 62–87 cm for spent fuel.
Smaller isn’t safer. Even drill cores (say, 40 cm tall by 10 cm wide) or fragments still need shielding on the same order, because near-surface dose depends on what’s inside, not the item’s size. At a million years, unshielded drill cores still translate into about48–67 cm of required concrete for vitrified waste and about46–72 cm for spent fuel.
Scale matters. Numbers per item are only half the story. Program scale multiplies these requirements: for example, Sweden plans roughly 6,000 spent‑fuel canisters. In France, there will be more than 50,000 vitrified-waste cylinders.
Concrete shielding thickness at one million years for spent fuel (full canister and drill core) and vitrified high-level waste (full cylinder and drill core). Results are shown for two protection targets: 0.02 mSv/h (brief, one-hour exposure) and 0.002 mSv/h (background-like)—ballpark in the absence of project-specific requirements
What this means in human terms
Heritage, not waste alone. If descendants encounter these materials—by curiosity, drilling, erosion, or chance—they won’t face a vanishing hazard but an enduring one, beyond legal timeframes and planning horizons. Our commitment to protect future people “to levels comparable to today” becomes concrete—literally—in centimeters of real shielding.
Justice and foresight. Thinking “per item” reframes responsibility. Are we designing containers—and contingencies—that keep each piece safe, including broken pieces? The ambition is that we should.
Design humility. Landscapes move; encounters may occur. The ethical stance is not to promise a perfect fortress forever, but to equip future people with buffers that still work: robust, intelligible, possibly maintainable shields—and the memory provisions (institutional handovers, markers, archives, time capsules) to keep that knowledge alive. Also, acknowledge that these wastes never become harmless.
So what now?
Build for fragments. Don’t just model intact packages; assume cores, partial breaches, and erosion-revealed segments—and assign them shielding, too.
Specify the long-lived drivers. Make a standard reporting of the deep-time isotopic loadings, because they determine both the danger and the shield.
Design the message with the material. If safety demands 50–90 cm at a million years, our markings and archives should be designed to last—and be rediscoverable—on comparable horizons. Or that should be the ambition.
Expand the lens. Apply similar analyses to other long-lived wastes that carry significant uranium-238 loadings.
Takeaway: this isn’t a new fear; it’s a clearer ethic. We owe the future not only sealed vaults and clever signs, but credible buffers—thicknesses you can measure with a ruler—matched to how matter behaves over time. The shield is not a metaphor; it’s a promise we can make, and keep.
Further reading
Claudio Pescatore, Beyond a million years: Robust radiation shielding for high-level waste Nukleonika, 70(3): 87-93.
In May, Anders Högberg was invited as keynote speaker at the National Library of Sweden. The invitation came from their Department for Research and Collection Management, which hosted a joint staff day. Högberg presented his research on heritage processes as futures-making practices. In his presentation Anders emphasised that we need new knowledge in order to rethink futures in novel ways. The discussion that followed on the presentation, largely focused on how we can create change to achieve this, what opportunities it might bring, but also which challenges we need to address in order to succeed.
National Library of Sweden. Photo Maria Aho
Anders Högberg, Professor of Archaeology UNESCO Chair on Heritage Futures
What if the true monuments of the nuclear age are not vaults, vitrified blocks, or warning markers—but fields of invisible light?
Gamma radiation is insidious. It leaves no ruin, no ash, no wound you can see. You don’t need to touch it. You don’t need to breathe it in. You simply pass by—and it passes into you. No trace is left on the soil. But a trace is left in you. And when the next person passes, they too receive the signal. Yet the source remains—unchanged, unweakened.
Most poisons are spent as they harm. Gamma radiation is not. It accumulates elsewhere, silently, without diminishing its source. A kind of ambient inheritance.
In a recent study, I calculated the gamma radiation field unleashed by humanity’s Uranium-238 (U-238) legacy. The results show that this field is not temporary. It is already present, slow to mature, but geologically assured and radiologically significant, beyond safety thresholds.
Mill tailings scattered across continents emit gamma radiation through uranium’s progeny. This signal will slowly fade over the next half a million years—but it will reach a baseline, unsafe value and will continue indefinitely.
Meanwhile, depleted uranium stockpiles—which emit almost no gamma today—are quietly maturing. From a few thousand years onward, their gamma output will rise steadily, eventually overtaking significantly that of tailings, peaking in two million years, and continuing unabated into geological time.
Most U-238 residues lie close to the surface—mill tailings, depleted uranium (DU) stockpiles, weapons testing sites, contaminated soils from mining and from exploded DU munitions. Even when their radiation does not cause immediate harm, it defines a long-term environmental signal whose meaning we have barely begun to grasp.
This raises questions not only of science, but of ethics, inheritance, and imagination:
What does it mean to leave behind a hazard that grows in potency over time?
How do we warn future beings of a danger concealed in ordinary soil or dust?
Should gamma radiation be seen not only as threat, but also as a marker of human agency?
Nuclear waste lasts a long time. But U-238 isn’t just persistent—it performs. It changes. It regenerates. It returns. And surprisingly, we don’t call it waste. We call it an industrial by-product.
And now we are not just leaving behind a signal—we are leaving a body.
About 4.5 million tonnes of U-238, mostly in oxide form, now reside in uranium tailings, DU, and spent fuel. It is a real, physical legacy—not symbolic, not speculative. This body must be put away—not forgotten, but deliberately placed and traced. Shielded, marked, and remembered.
We can still act. We can treat uranium’s gamma legacy not as an afterthought, but as a defining part of our industrial inheritance. This won’t undo the past—but it may shape how future generations understand what we’ve left them.
We often speak of the nuclear age as bracketed—confined by Cold War dates or the operational lifespan of reactors. But its material consequences are just beginning. Care begins by acknowledging and tending to what endures.
Claudio Pescatore is a member of the UNESCO Chair on Heritage Futures at Linnaeus University
Bebyggelsehistorisk Tidskrift (Nordic Journal of Settlement History and Built Heritage): Urban transformation, heritage processes and social sustainable futures by Ulrika Söderström & Anders Högberg.
Short summary:
In this study, we use three case studies to discuss heritage processes as future-building practices. Through examples from urban regeneration processes in three Swedish cities, we discuss how these processes have contributed to social sustainability. The case studies are the Caroli neighbourhood in Malmö (transformed 1967-1973), the Valnötsträdet neighbourhood in Kalmar (transformed 2008-2018) and the ongoing transformation of Kiruna city. Our findings show that the cultural heritage processes activated in urban regeneration processes do not always promote socially sustainable future-making practices. We conclude that an engagement in different forms of future-making is crucial for heritage processes to contribute to long-term sustainable urban development. We suggest that this requires a way of thinking and acting that includes change and transformation. Our findings are conceptualised in a model that we hope can be used to understand heritage processes as future-making practices in urban transformation projects.
Bebyggelsehistorisk Tidskrift is a Nordic forum for research and debate on the history of the built environment. It is the Nordic region’s leading academic journal on the history of the built environment. The periodical presents the latest research on the history of the built environment, and also provides a forum for discussing the discipline in practice when buildings and heritage environments are being conserved.
Anders Högberg held a keynote lecture at the conference “Kulturarvsforskning i Sverige 2025” – Cultural Heritage Research in Sweden 2025, organised by the Swedish National Heritage Board 20-21 March 2025 in Stockholm. Keynote paper: ‘Cultural heritage research 2025 – some thoughts on where we stand and questions for the future’.
Ulrika Söderström also presented her dissertation at the conference: “Cultural heritage as a resource in socially sustainable urban development: A designed living environment for the future”.
On the 25th of February 2025 Gustav Wollentz presented and participated in a panel discussion at the conference “The Houses, the History, and the Future” (Husen, historien och framtiden) that was organized in Gothenburg by Gothenburg University and multiple other partners in the region. There were around 140 heritage professionals attending the conference, mostly working with, and researching on, the conservation and restoration of buildings.
Gustav contributed to the final part of the conference, where future challenges and opportunities were in focus. Gustav presented the work on Strategic Foresight he has been carrying out together with ICCROM, including the Horizon Scanning looking 15 years ahead, and the work for the pan-European ARCHE project, with the goal to produce a new Strategic Research and Innovation Agenda for Heritage in Europe.
In the presentation, Gustav focused on four specific opportunities for action related to future change:
Heritage to shape more desirable, sustainable and just futures,
Heritage to increase wellbeing,
Heritage to understand and reveal the humanity in individuals,
Heritage to cope with loss and change.
The presentation and panel discussion were very well received and there was a large interest to further explore Strategic Foresight.
On December 3, 2024, the university management invited to a theme day in Växjö about Linnaeus University and the future. A recording of the event is available here https://play.lnu.se/media/t/0_tb0d3lc4
Cornelius Holtorf participated live in a panel discussion with Marie Hedberg, Pro Dean at the Faculty of Social Sciences and Jörgen Forss, Vice Dean at the Faculty of Technology. Marcelo Milrad from the Faculty of Technology joined via link. The panel was chaired by Kerstin Årmann from the Office of External Relations.
Cornelius Holtorf in a panel discussion at the Future Day, Linnaeus University.
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