US Energy Department conducts underground explosive test in Nevada to improve detection of low-yield nuclear explosions

The US has conducted a non-nuclear underground experiment to enhance its ability to detect low-yield nuclear explosions that it explicitly linked with a test that Washington suspects China carried out in 2020 – an accusation Beijing denies.

The US Department of Energy announced on Wednesday that the National Nuclear Security Administration (NNSA) conducted a “subsurface, non-nuclear chemical high-explosive” experiment at the Nevada National Security Site, which it said aimed to “increase the United States’ ability to detect low-yield nuclear explosions”.

The experiment, which did not involve any nuclear explosions, collected data to validate scientific models and refine algorithms critical to US nuclear explosion detection capabilities.

The Nevada test highlights the constraints of verifying suspected low-yield nuclear tests. Despite Washington’s allegation that Beijing has covertly conducted a nuclear test at the Lop Nur testing site in June 2020, Beijing denied the accusation, and the international nuclear-test monitoring body has said the available seismic data cannot establish the cause of the events with confidence.