United States Marine Corps Capt. Adam J. Birchenough (squatting), the reaction force company commander with the Chemical Biological Incident Response Force, II Marine Expeditionary Force, explains points of entrance into the stimulated, contaminated Guardian City, July 23, during Scarlet Response. Soldiers from 3rd Armored Brigade Combat Team, 3rd Infantry Division, assisted Marines and Sailors with the CBIRF, July 22 and 23, as part of the exercise. “The 3rd Infantry Division Soldiers did a fantastic job or cordoning the sensitive environment,” said Birchenough. “They took the initiative to not just secure the buildings but, once secured, to bring people out of those buildings and the forces we already had on ground. They were huge force multiplier for this exercise.”