“An RDD [Radiological Dispersion Device] detonated in a major metropolitan area could result in economic costs in the billions of dollars as a result of evacuations, relocations, cleanup, and lost wages. Radioactive sources such as Cobalt, Cesium, Americium, and Iridium are used worldwide for many legitimate purposes and are located at thousands of sites in the United States and around the world. Since many of the sites that use these materials, such as medical, university, research, and industrial facilities are open environments, these facilities are more vulnerable to adversaries that may target these materials and are more difficult to secure. In looking at the risk, we must include not only outside terrorists attempting to steal radioactive sources as potential adversaries, but also insiders who work at these facilities who could have intimate knowledge of security procedures and vulnerabilities.”
Anne Harrington, National Nuclear Security Administration’s Deputy Associate Administrator for Defense Nuclear Nonproliferation, Senate Homeland Security and Governmental Affairs Committee, June 12, 2014. For more on insider threats, see Mathew Bunn and Scott Sagan’s "A Worst Practices Guide to Insider Threats: Lessons from Past Mistakes.” For more about the hearing, see the GAO Report on Radiological Security.