Oklo Receives DOE Startup Authorization for Groves Isotope Reactor
Oklo Inc. has cleared a major regulatory milestone for its Groves Isotope Test Reactor in Lockhart, Texas, after the U.S. Department of Energy granted startup authorization under the agency’s Reactor Pilot Program. The approval lets Oklo begin loading nuclear fuel, run startup testing, and move toward first criticality at the facility.
The pace of the buildout stands out. Oklo went from breaking ground to DOE startup authorization in just over ten months, a span that included constructing the reactor facility, standing up the operating organization, training personnel, writing nuclear programs and procedures, and sourcing fuel and major equipment commercially.
Groves is a low-power test reactor, but it’s built to commercial scale, which is the point: Oklo wants a repeatable playbook for siting, building, commissioning, and operating reactors, with a known cost and schedule, that it can carry into future isotope production projects. The facility is privately financed and sits on private land, with full-scale civil excavation, construction, and component sourcing handled the way a commercial deployment would be.
Oklo co-founder and CEO Jacob DeWitte framed the timeline as evidence the advanced nuclear sector can move faster than commonly assumed, crediting the greenfield site, full-scale construction, and commercial procurement of fuel and components for the pace. DOE’s Mike Goff, Principal Deputy Assistant Secretary for Nuclear Energy, credited the Reactor Pilot Program’s structure for helping the company accelerate.
Getting to this point required a readiness review, the last gate before startup authorization. A multidisciplinary DOE team checked that facility procedures and staff training were adequate, that the built facility matched its approved design, that safety equipment worked, and that required safety management programs were in place. Notably, Oklo built those safety programs itself rather than leaning on an existing framework from an established operator or national lab.
Co-founder and COO Caroline DeWitte described the project as building “operational muscle” across the company — standing up training, security, quality assurance, and environment/health/safety programs from scratch. That institutional capability, along with the qualified suppliers and approved operating programs developed for Groves, is meant to carry forward into Oklo’s other projects, cutting execution risk on future builds.
The isotopes Groves is meant to help produce domestically have applications spanning cancer care, manufacturing, scientific research, space exploration, and national security — a supply chain the U.S. currently leans on imports to fill.
Groves joins a small list of Reactor Pilot Program participants moving through DOE’s authorization pipeline, and its progress will be watched as a signal of how quickly the broader advanced reactor sector — including Oklo’s commercial Aurora powerhouse plans — can move from paper to operating hardware.