An aerial view of the Muscatatuck Urban Training Center in North Vernon, Ind., which simulates a city destroyed by a "dirty bomb." MUTC was used by Joint Task Force Civil Support during training exercise Vibrant Response 11.1, March 11-19. This exercise is one of many designed to test Northern Command and U.S. Army North's ability to perform its mission to save lives, prevent further injuries, and provide temporary critical support during a chemical, biological, radiological, nuclear or high-yield explosive incident in the United States and its territories and possessions.