Holtec files safety report for two SMR-300 units at Palisades with the NRC
Victoria Shinder2 min readHoltec has submitted the Preliminary Safety Analysis Report for Pioneer 1 and 2, two planned SMR-300 reactors at the Palisades Energy Center in Michigan, to the US Nuclear Regulatory Commission, World Nuclear News reports. The filing completes the second phase of Holtec's construction permit application.
How the application is staged. Holtec opened the process in December 2025 with a request for a limited work authorisation and an Environmental Report. A limited work authorisation allows some construction to begin before a construction permit or combined licence is granted. The NRC accepted that request and docketed it in February, and Holtec expects the regulator's draft Safety Evaluation Report on it in December 2026. The new report supplies the detailed technical and safety case for building the two units; Holtec calls it the most significant step so far toward the regulatory basis for the plant. Before approving the project the NRC needs a safety evaluation and an environmental assessment, and a separate licence application will be needed to operate the units once built.
What the reactor is. The SMR-300 is a pressurised water reactor rated at about 300 MW of electricity, or 1,050 MW of heat for process applications. The same site holds the single-unit 805 MWe Palisades reactor, which shut in 2022 and which Holtec is bringing back into service. The Pioneer units are planned to start operating in the early 2030s.
Some groundwork is already allowed. An NRC exemption granted on 28 August cleared the installation of permanent support-of-excavation and cutoff-wall systems for both units — diaphragm walls, soldier-pile soil-mix walls and perimeter cutoff walls, with tiebacks or struts where needed. Holtec says these will prepare stable excavation and foundation conditions so that construction can move faster once the limited work authorisation is approved, and that the walls will later be left in place and backfilled.
Holtec's next tasks, it says, are a Class 2 construction cost estimate, a 4D simulation of the whole plant's construction sequence and the confirmatory safety analyses for the Final Safety Analysis Report. The company thanked the Department of Energy for its support and the NRC for what it called a risk-informed and responsive approach.
Why it matters
Several US small-reactor projects are now moving through the NRC in pieces — early works, construction permit, operating licence — rather than in one application. Holtec's sequence shows the payoff and the dependency: digging can start early, but the schedule now hangs on the December safety evaluation and on a cost estimate that has not yet been published.