A U.S. Soldier with the 43rd Civil Support Team, South

A U.S. Soldier with the 43rd Civil Support Team, South Carolina Army National Guard, opens a box with potential radiation, in a building during a radiological training exercise at Savannah River Site in support of Ardent Sentry May 20, 2013, near Allen, S.C. Ardent Sentry is a North American Aerospace Defense Command and U.S. Northern Command (USNORTHCOM)-directed exercise focusing on defense support of civil authorities in response to simulated weather, security and disaster contingencies. While Ardent Sentry is primarily a command post exercise, several field training events were conducted at various locations within the USNORTHCOM area of responsibility. (U.S. Army National Guard photo by Sgt. Erica Knight/Released)