Federal Regulators Clear Dow to Build Four Advanced Reactors at Seadrift

The Nuclear Regulatory Commission (NRC) on Monday issued a construction permit for four advanced nuclear reactors at Dow’s Seadrift Operations complex in Calhoun County, on the Gulf Coast between Houston and Corpus Christi. The agency called it the first construction permit for a high-temperature gas-cooled reactor in nearly 60 years.

The Long Mott Generating Station would run four Xe-100 reactors designed by X-energy, each rated at 80 megawatts of electricity. According to the NRC, the plant would “primarily generate high-temperature steam for industrial use” at the Seadrift site and export its excess electricity to the grid.

The permit allows construction, not operation. Before it loads fuel, Long Mott Energy, the Dow subsidiary that holds the permit, must win a separate operating license from the NRC.

Dow has not decided to build. Its release says the permit “does not represent a final decision by Dow to proceed,” and that the project still needs engineering work and a review by the company’s board of directors.

“As we move forward, we will continue to evaluate the project through the lens of competitiveness, execution readiness, and capital affordability before any decision regarding construction is made,” said Edward Stones, Dow’s business vice president for energy and climate.

If the board approves, Dow says, construction could begin later this decade, with startup early in the 2030s.

The reactors would replace equipment at the end of its life. Seadrift now gets its power and steam from a natural gas cogeneration plant and gas turbines next door, and the company told the NRC those units are “reaching the end of their operational life,” according to the agency’s environmental notice in May.

Long Mott Energy filed its application on March 31, 2025. NRC Chairman Ho K. Nieh said the agency “delivered on the 18-month schedule.” The NRC issued an environmental assessment with a finding of no significant impact rather than a full environmental impact statement. The permit is the third the agency has issued for an advanced reactor this year.

The Xe-100 is cooled by helium, and its fuel is packed into pebbles that move through the core. According to the Texas Tribune, the units will not need the tall concrete containment buildings of existing reactors or the 10-mile emergency planning zone around them. X-energy’s reactor was one of two the Energy Department chose in 2020 for its Advanced Reactor Demonstration Program, which awarded the company $80 million in initial funding.

The plant has critics on the bay. San Antonio Bay Waterkeeper, led by retired Seadrift shrimper Diane Wilson, challenged the application, and the NRC dismissed the challenges, the Tribune reported. “Frankly, it’s outrageous,” Wilson told the Tribune. Edwin Lyman of the Union of Concerned Scientists told the paper the fuel “has vulnerabilities.”

Spent fuel from the four reactors would be stored at Seadrift with no end date, according to the Tribune, because the federal government still has no permanent disposal site for it. If Dow builds, a Texas chemical plant will make its own power and steam, and the waste will stay on the Texas coast until Washington decides where it goes.