Zion's two Westinghouse PWRs on Lake Michigan were dismantled by EnergySolutions under a first-of-its-kind 2010 license-stewardship deal, and in November 2023 the NRC released most of the site for unrestricted use. Only the dry-cask spent fuel storage pad remains licensed, now held by Constellation.
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Current state
| Status | License terminated |
| Country | United States |
| Location | Zion, Illinois |
| Site | Zion Nuclear Power Station |
| Units | Unit 1, Unit 2 |
| Unit count | 2 |
| Reactor types | PWR |
| Net capacity (MWe) | 2,196 |
| Owner / licensee | Constellation Energy Generation (ISFSI licensee) |
| Decommissioning contractor | ZionSolutions (EnergySolutions) |
| Strategy | Mixed |
| Final shutdown | 1998 |
| Decommissioning start | 2010-09 |
| Target completion | 2023 |
| Spent fuel | 2,226 fuel assemblies in 61 dry casks on the on-site ISFSI, now Constellation's responsibility. |
| Notable issue | Model for the 'license stewardship' transfer of a shut-down plant to a decommissioning contractor. |
Notes
Strategy "Mixed": SAFSTOR 1998-2010, then accelerated DECON. Capacity 2 x 1,098 MWe per WNA. Not on the NRC list of sites undergoing decommissioning as of Sept 2026; ISFSI remains licensed.
Timeline
- 1998 — Commonwealth Edison declared both Zion units permanently shut down. (source)
- 2010-09 — EnergySolutions took ownership of the plant through its license stewardship program. (source)
- 2023-11 — The NRC approved partial site release, releasing all but the ISFSI for unrestricted use. (source)
- 2023-11-16 — EnergySolutions announced completion of the project and license transfer back to Constellation. (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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About EnergySolutions
Related sites
- Brennilis (Monts d'Arrée EL-4) Active dismantling · France
- Crystal River Unit 3 Site restoration · United States
- Dresden Unit 1 SAFSTOR · United States
- Duane Arnold Energy Center Restart planned · United States
- Fermi Unit 1 (Enrico Fermi Atomic Power Plant) SAFSTOR · United States
- Fort Calhoun Station Site restoration · United States
- GE Vallecitos (VBWR and EVESR) Active dismantling · United States
- Humboldt Bay Power Plant Unit 3 License terminated · United States
See all 72 sites in the Nuclear Decommissioning Tracker →
Sources
- Former US reactor site released for unrestricted use — World Nuclear News, checked 2026-10-11
- Zion Nuclear Power Station Decommissioning Successfully Completed — EnergySolutions (primary), checked 2026-10-11
- Partial Site Release, Zion Nuclear Power Station, Units 1 and 2 — U.S. NRC (primary), checked 2026-10-11
- Decommissioning Nuclear Facilities — World Nuclear Association, checked 2026-10-11