Oklo Groves Isotope Test Reactor, Texas, USA

Oklo is a U.S. advanced nuclear technology company developing small reactors for clean power and for the production of radioisotopes. Its isotope business, Oklo Isotopes, builds on the company's 2025 acquisition of radioisotope producer Atomic Alchemy.

The Groves Isotope Test Reactor, near Lockhart in Caldwell County, Texas, is a pool-type, water-cooled test reactor built on a greenfield site on private land. It was selected for the U.S. Department of Energy's Reactor Pilot Program and reached first criticality in 2026, less than a year after construction began, the first reactor under the program to do so on privately owned land. Groves is the proving ground for Oklo's future commercial isotope production facilities, which will supply materials for oncology diagnostics and therapy, industry, research and national security.

Nuclear facilities are held to the highest safety standards in the built environment, and seismic instrumentation is part of that framework wherever a reactor is built. [Department of Energy nuclear safety requirements call for instrumentation that records ground motion at the site and supports post-event decisions on continued operation.] Even in a region of moderate seismic hazard, the facility must be able to show, with measured data, what any earthquake did to its structures and systems.

Groves also faced an exceptional schedule. Oklo set out to go from groundbreaking to startup faster than any comparable reactor project, so every system on site had to be specified, delivered, installed and commissioned on time and to nuclear-grade quality. It needed a monitoring supplier with proven experience in nuclear facilities and a local partner able to execute without delays.

Estructura supplied, installed and commissioned a seismic monitoring system for the Groves facility, built on GeoSIG instrumentation that is already in service at nuclear plants around the world, including the Beznau nuclear power plant in Switzerland and Unit 4 at Chernobyl. [The system combines a free-field triaxial accelerometer with AC-7x accelerometers on the reactor building foundation and at an upper structural level, recorded by GMSplus digital recorders with alarm outputs to the facility's control room.]

If ground shaking exceeds predefined levels, operators are alerted immediately and can follow the facility's established procedures. Every event is recorded, time-stamped and archived, producing the documented record that regulators and Oklo's own engineers rely on. The same design can be replicated as Oklo moves from a single test reactor to multi-reactor commercial production facilities.

Another solution using GeoSIG instruments and a capable partner, showing that quality and reliability can also be cost-effective.