A radioactive wasp nest discovered near a nuclear waste tank at the Savannah River Site in South Carolina tested over 10 times the federal contamination limit. The U.S. Department of Energy says the nest poses no health risk,

Workers at a site in South Carolina that once made key parts for nuclear bombs in the United States have found a radioactive wasp nest but officials said there is no danger to anyone.

Four radioactive wasp nests may indicate previously undetected environmental contamination at the decades-old Savannah River Site. Here’s what to know.