MUD SPLASH Students in the basic course at the Chemical, Biological Incident Response Force remove debris at the opening as they try to enter a simulated building collapse in search of survivors at Indian Head, Md., Dec. 18, 2008. More than 400 Marines, sailors and civilians are assigned to the specialized unit that trains around the United States to decontaminate and extract victims from a disaster site. SHARE: Download: Full Size (0.09 MB) Credit: VIRIN: 121764-H-IZH94-923.jpg Photo Gallery