Chooz A, a Franco-Belgian PWR built into a cavern and operated from 1967 to 1991, is EDF's lead PWR dismantling project. EDF lifted the 190-tonne reactor vessel out of its pit in March 2025, a first in France, but vessel cutting was paused in late 2025 after worker contamination events prompted an ASNR-requested action plan.
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Current state
| Status | Active dismantling |
| Country | France |
| Location | Chooz, Ardennes |
| Site | Chooz |
| Units | Chooz A |
| Unit count | 1 |
| Reactor types | PWR |
| Owner / licensee | EDF |
| Decommissioning contractor | Westinghouse Electric France / Nuvia (vessel) |
| Strategy | Immediate dismantling |
| Final shutdown | 1991 |
| Notable issue | Vessel segmentation suspended in late 2025 after three declared contamination events in 2025. |
Notes
EDF had planned vessel cutting for Q1 2026; resumption not confirmed in the sources reviewed.
Timeline
- 1967 — Chooz A entered service. (source)
- 1991 — Chooz A was shut down. (source)
- 2025-03 — EDF extracted the 190-tonne reactor vessel from its concrete pit, a first in France. (source)
- 2025-11 — Vessel cutting was halted pending an action plan after contamination events. (source)
- 2025-12-08 — All Chooz A work sites were stopped for two weeks of radiation-protection awareness. (source)
The timeline is append-only: corrections are added as new entries. Stated targets appear in the current-state table, never as milestones.
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Related sites
- Biblis Nuclear Power Plant (Units A and B) Active dismantling · Germany
- Brennilis (Monts d'Arrée EL-4) Active dismantling · France
- Brokdorf Nuclear Power Plant (KBR) Active dismantling · Germany
- Brunsbüttel Nuclear Power Plant (KKB) Active dismantling · Germany
- Chinshan Nuclear Power Plant Fuel removal · Taiwan
- Crystal River Unit 3 Site restoration · United States
- Doel Nuclear Power Plant (Units 1-3) Shut down · Belgium
- Dounreay (DFR and PFR fast reactors) Active dismantling · United Kingdom
See all 72 sites in the Nuclear Decommissioning Tracker →
Sources
- Démantèlement nucléaire à Chooz : un plan d'action demandé à EDF après une augmentation des cas de contamination — France 3 Grand Est, checked 2026-10-11
- Démantèlement du réacteur Chooz A : trois étapes et quatre points d'arrêt — ASNR (primary), checked 2026-10-11
- Démantèlement de la cuve du réacteur de Chooz A — Nuvia (primary), checked 2026-10-11
- Nuclear Power in Belgium — World Nuclear Association, checked 2026-10-11