Wallsten, Krook et al., hibernating copper under Swedish cities (2011-2016)

Disposition: stated. One research group (Linköping University, Resources 2.0 project), several papers; read from abstracts, a university press release and long search text on 2026-10-19, not the full papers.

What: a body of work that maps the copper, iron and aluminium left in the ground when urban infrastructure is disconnected but not removed ("hibernating"), and asks when it is worth digging up. Why: it is a town-scale ore body that already sits under municipal land, and the first people to prospect it used the city archive. Bears on macro-view (the resources leg as "when is extraction economic") and on thread-convivial-computation (what a community could own from its own past infrastructure).

Key points, as read:

• The local power grids of Gothenburg and Linköping hold 0.04-0.05 t of copper per subscriber. Almost 20% of Gothenburg's grid copper is out of use; in Linköping it is at most 5%. Recovering the cables on their own is not economic at 2011 copper prices; doing it during other maintenance work can be (Krook et al. 2011, J. Cleaner Production 19:1052-6). https://archive.metabolismofcities.org/publication/471 ; text excerpt at https://www.kth.se/social/upload/4ea9a6acf27654583e000001/Krook%20et%20al%202011.pdf
• Under Norrköping (~135,000 people) there are about 5,000 t of iron, copper and aluminium in disconnected cables and pipes, a quarter of the installed systems' weight. At least 560 t is copper on municipal land, then worth ~SEK 28M. Swedish cities hold 4-5 kg of disconnected copper per person. The word "urk" on old maps means urkopplad, disconnected. The prospecting used the Norrköping City Archive, the municipality and private operators' records (LiU press releases, 2016). https://liu.se/en/article/welcome-to-the-world-of-the-urks ; https://liu.se/en/article/the-norrkoping-iron-and-copper-mine
• Hibernation is not documented in the operators' GIS; "the comatose DC power grid" turns up as a surprise when digging. Hibernating cables are not legally waste, so nobody is obliged to recover them (Wallsten et al. 2013, "A Cable Laid Is a Cable Played", J. Urban Technology). https://doi.org/10.1080/10630732.2013.809222
• Method: GIS plus material flow analysis, tied to "the social practices that arrange material flows in the city" (Wallsten et al. 2015, Resources, Conservation & Recycling 103:85-97, abstract read in full). https://ideas.repec.org/a/eee/recore/v103y2015icp85-97.html
• Swedish Geological Survey: infrastructure takes 28% of Swedish copper use, and cables are left in the ground "because it becomes too expensive to dig up" (search text). https://www.sgu.se/en/mineral-resources/metal-and-mineral-recovery/urban-mining

• Added 2026-10-21 (trail-2026-10-21, search text). With Kabel-X, which pulls the conductor out and leaves the jacket in place as a fibre duct, extraction falls to ~200 SEK/m and the clean conductor fetches ~3x a whole cable. Done as part of a fibre install, recovered plastic-insulated copper nets 60-280 SEK per metre; dug-up recovery alone almost never pays (Wallsten et al. 2015, "Urban infrastructure mines", J. Cleaner Production). https://www.diva-portal.org/smash/get/diva2:845703/FULLTEXT01.pdf
• Added 2026-10-21 (abstract in full). Recovery in cities was not yet economic for grid managers, but "in rural areas, however, both separate and integrated recovery of hibernating cables seem straightforwardly profitable, especially for obsolete copper cables belonging to the regional communication network" (Krook et al., "Urban mining: prospecting for metals in the invisible city"). https://doi.org/10.13140/2.1.3141.0882
• Added 2026-10-21 (search text). Linköping's grid had an "unspoken" policy to recover urks, but it never reached project plans, and contractors do nothing beyond the plan (Krook et al. 2011). Urks "resist categorisation"; recovery waits on "fault lines between actors and priorities" (Wallsten & Johansson 2016, Science, Technology & Human Values, abstract). https://doi.org/10.1177/0162243916634866 . Wallsten's stated "normative stance is that the Urk World should be mined" (DiVA abstract, http://diva-portal.org/smash/record.jsf?pid=diva2:872812).

Not yet read: Wallsten's thesis, The Urk World: Hibernating Infrastructures & the Quest for Urban Mining (2015), http://liu.diva-portal.org/smash/get/diva2:872787/FULLTEXT02.pdf (unreachable from this host on 2026-10-21; see dead-ends)

Backlinks: macro-view, telco-copper-retirement-2023-2026, trail-2026-10-21, bt-openreach-copper-recovery-2026, trail-2026-10-19