X-Energy, Inc. said Friday the U.S. Nuclear Regulatory Commission (NRC) has completed a safety review of its proposed Texas reactor project, advancing a four-unit development toward a permit but not authorizing construction.
The company said the NRC staff’s Final Safety Evaluation Report found the plant-and-site proposal met the agency’s safety requirements for a construction decision. X-energy said staff assessed the reactor’s design criteria, preliminary design, safety analyses, risk assessment, and research and development work.
The proposed Long Mott Generating Station would place four Xe-100 units at Dow’s Seadrift site in Calhoun County, Texas. NRC materials put each unit’s electric capacity at about 80 megawatts and say the reactors also would supply heat for Dow’s industrial uses. Long Mott Energy LLC filed its construction-permit application March 31, 2025; the NRC accepted it for review May 12 that year.
The NRC made a separate environmental review available in May 2026. A Federal Register notice said one-time exemptions allowed the application to use an Environmental Assessment and a Finding of No Significant Impact instead of an environmental impact statement.
The Department of Energy (DOE) lists the project at 320 megawatts of electric capacity under its Advanced Reactor Demonstrations Program (ARDP). DOE says the program uses industry cost sharing to address the licensing, construction and operational risks of first-of-a-kind reactors, while encouraging follow-on orders. X-energy says the review may help make assessments of future Xe-100 proposals more efficient, though each application would be evaluated individually.
The safety review does not grant permission to build. Long Mott Energy would need a construction permit and, later, separate operating licenses from the NRC before running the units.
X-energy reported the review’s completion ahead of the NRC project page’s November 2026 target for the final safety evaluation. The page still gives the construction-permit decision date as “TBD” and does not confirm an Oct. 30 completion.
