The U.S. Nuclear Regulatory Commission (NRC) has completed the environmental assessment for the proposed Long Mott Generating Station in Texas, which is a major step forward in licensing what could become North America’s first grid-scale advanced nuclear reactor deployed at an industrial site.

The project, planned at Dow’s Seadrift manufacturing complex in Texas, would use four X-energy Xe-100 high-temperature gas reactors. The plant is designed to provide both electricity and industrial steam to support operations at the site, which manufactures billions of pounds of materials annually for sectors including food packaging, pharmaceuticals, solar technology, and electrical applications.

The NRC concluded that the project’s environmental impacts would not be significant and issued a Finding of No Significant Impact (FONSI), eliminating the need for a broader Environmental Impact Statement (EIS).

Faster review path for an industrial nuclear project

According to the U.S. NRC and X-energy, the regulator opted for an environmental assessment rather than a full EIS because the proposed facility is located within an existing industrial site and was determined to have a relatively limited environmental footprint.

Long Mott Energy, a wholly owned Dow subsidiary, submitted its construction permit application in March 2025. The NRC began environmental review activities in June and completed the assessment in less than a year, ahead of schedule.

NRC Executive Director for Operations Mike King said the milestone demonstrates that reviews can be completed efficiently while maintaining environmental protections. The agency added that its analysis covered potential effects on air quality, water resources, and local habitats.

X-energy stated that the review benefited from earlier pre-licensing work on the Xe-100 reactor platform and a construction permit package supported by year-long field surveys, groundwater monitoring, and consultations with Texas agencies, including the Texas Parks and Wildlife Department and Texas Historical Commission.

The NRC expects to complete the project’s safety review later this year under the 18-month timeline established through Executive Order 14300. A final agency decision on the construction permit would follow, although Dow would still need to obtain separate operating licenses before the plant could begin operation.

Four-reactor plant aimed at industrial decarbonization

The Long Mott project is centered around X-energy’s Xe-100 advanced reactor design. Each unit is designed to produce approximately 80 MW of electricity and 200 MW of thermal energy in the form of high-temperature steam.

Together, the four reactors would deliver up to 320 MWe and 800 MW thermal output, enabling the system to provide both baseload electricity and industrial process heat.

The project is expected to reduce emissions from Dow’s Seadrift site by roughly 440,000 tonnes of carbon dioxide annually. If built, Long Mott would serve as an important demonstration project for deploying advanced nuclear technology in industrial settings. 

The facility has been described by Dow and X-energy as the first grid-scale advanced nuclear installation in North America specifically intended to serve an industrial operation. The project is also supported by the U.S. Department of Energy’s Advanced Reactor Demonstration Program, which backs commercialization efforts for next-generation nuclear technologies.