Pvt. 2 Nicholas Carroll of Osceola, Mo., pulls guard duty at the entry gate to Forward Operating Base Schoonover at Fort Hunter Liggett, Calif. Carroll is with the 561st Movement Control Team Detachment out of Springfield, Mo. Forward Operating Base Schoonover is one of several sites for Exercise Grecian Firebolt 2012, the U.S. Army Reserve's largest and only signal exercise.