ATOMIC CITY, IDAHO — Three companies at Idaho National Laboratory and one company in central Utah activated new types of reactors in the summer of 2026. The official record of the event states that the U.S. Department of Energy delivered and exceeded the milestone of achieving criticality of four advanced reactors by the July 4, 2026, deadline.

President Donald Trump issued an executive order regarding nuclear energy on May 23, 2025. The deadline set by President Trump in his May 2025 executive order was July 4, 2026, for the U.S. Department of Energy to achieve criticality in three advanced reactors. The relevant number is three, which is the number of advanced reactors that achieved criticality by the July 4, 2026, deadline set by President Trump.

The Department of Energy accelerated reactor permitting processes in 2025. The White House stated that the administration streamlined nuclear testing by eliminating or expediting internal environmental reviews to meet aggressive deadlines.

Deployable Energy achieved a sustained chain reaction in its test reactor at Idaho National Laboratory in 2026. Lance Maul is the chief operating officer at Deployable Energy.

Idaho National Laboratory has served as America's nuclear energy test grounds since 1949. The facility covers 900 square miles. Research titled Lagoon Seepage Testing Procedures for Central Facilities Area (CFA) Sewage Lagoons at Idaho National Laboratory Butte County, Idaho April 2014 was published in 2014.

Arco, Idaho is located near Idaho National Laboratory. The population of Atomic City, Idaho is 52. Vickie O'Haro owns the Atomic City Bar & Store and the Atomic Motor Raceway.

According to KUNC, the Atomic City Bar, located near Idaho National Laboratory, is directly affected by the activation of new types of reactors at the laboratory, as its regular customers mostly work at the laboratory. Vickie O'Haro said local businesses reliant on laboratory workers are directly affected by the activation of new reactors.

The federal commission overseeing commercial nuclear development has lost hundreds of staff members, including safety experts, due to cuts by the Trump administration and resignations. PureSource News previously reported that the Department of Energy selected five states as Nuclear Campus Finalists.

Polling indicates growing support for the U.S. emphasizing nuclear power more broadly. A March Gallup poll indicates that a majority of Americans oppose having a nuclear energy plant in their area.

Why It Matters

The activation of four advanced reactors fulfills a presidential deadline while national polling shows a divide between broad support for nuclear emphasis and local opposition to nearby plants. This development proceeds as the federal oversight commission has lost hundreds of staff members, including safety experts, due to administrative cuts and resignations. The situation shows a contrast between accelerated permitting processes and reduced regulatory capacity during expanded testing operations.