A radioactive wasp nest was found next to a site in South Carolina that once made key parts for nuclear bombs.

The hazardous insect abode was located near a set of tanks filled with liquid nuclear waste, although the team didn’t detect any leaks. Instead, experts believe the nest set off Geiger counters through what’s known as “onsite legacy radioactive contamination.

A terrifying discovery was made at a nuclear facility in South Carolina: radioactive wasps. Radiological Control Operations found a wasp nest on a post close to a tank at the Savannah River Site in Aiken, according to a report from the U.S. Department of Energy.