Wasps living around a Cold War-era nuclear facility in South Carolina have built at least four radioactive nests, raising questions about their source of hazardous material and the extent of environmental contamination, according to a report by The New York Times.

This is an indicator that there are contaminants spread across this area that have not been completely encased and protected,” said Dr. Timothy Mousseau, a biologist at the University

Workers at South Carolina's Savannah River Site, a nuclear facility, found a radioactive wasp nest with radiation levels 10 times higher than federal regulations allow.