"OAK RIDGE — In early 2014, evidence of radioactive pollution was discovered in the city of Oak Ridge's sewage treatment facility on the west side of town.

The unwelcome surprise was blamed on technetium-99 that had migrated from a demolition project at the federal government's K-25 uranium-enrichment plant on the other side of the Clinch River.

The radioactive contaminants, which can be mobile in the environment, had infiltrated pipelines leading to the sewer system. Although the radioactivity reportedly didn't not pose a health threat to workers at the plant or drinking water supplies in the area, it prompted a number of cleanup actions — including efforts to remove the technetium in the sewage treatment systems."

Frank Munger reports for the Knoxville News Sentinel December 29, 2015. [2]