The Nuclear Regulatory Commission granted Holtec International an exemption on August 28, 2026, permitting the company to begin installing permanent support-of-excavation and cutoff-wall systems at the Palisades Energy Center in Covert Township, Michigan. The authorization allows Holtec to proceed with these foundational works for Pioneer Units 1 and 2 before receiving a Limited Work Authorization. The regulator issued an Environmental Assessment and Finding of No Significant Impact on August 25, concluding that the early activities would not significantly affect the human environment or historic properties.
What it means
The exemption permits Holtec to install diaphragm walls, soldier-pile soil-mix walls, and perimeter cutoff walls with tiebacks or struts. These systems are designed to stabilize excavations, protect adjacent structures and utilities, manage groundwater pressures, and support safe construction for the Nuclear Island, Turbine Island, and Balance of Plant areas. Holtec submitted the request on December 31, 2025, as part of Part 1 of its phased Construction Permit Application. The regulator determined the exemption is authorized by law under 10 CFR 50.12 and poses no undue risk to public health and safety.
Holtec will retire the support walls in place and backfill the space between the walls and permanent structures to grade. During excavation, the company will perform geologic mapping and data collection, then notify the NRC when the excavation is open for inspection. Holtec must also account for the retired walls in soil-structure interaction analyses. The exemption does not constitute a commitment by the NRC to issue a Limited Work Authorization or a construction permit. Pioneer Units 1 and 2 are expected to deploy 680 megawatts of energy using Holtec’s SMR-300 advanced small modular reactor design. The project represents the first commercial nuclear reactor in the U.S. to be repowered after permanent shutdown.
Key facts
- NRC granted exemption on August 28, 2026
- Holtec submitted request on December 31, 2025
- Environmental Assessment issued August 25, 2026
- Location: Palisades Energy Center, Covert Township, Michigan
- Pioneer Units 1 and 2 expected capacity: 680 megawatts
- Reactor model: SMR-300 advanced small modular reactor
- Holtec operates three large U.S.-based nuclear fabrication facilities
- Holtec holds over 200 granted patents as of June 30, 2026
Source: Nuclear Regulatory Commission announcement