Marines training in the Marine Combat Instructor of Water Survival course drill rescues with their classmates at the Marine Corps Base Hawaii pool, Dec. 12, 2014. A total of 18 Marines were tested this week. (U.S. Marine Corps photo by Christine Cabalo/Released) - Marines training in the Marine Combat Instructor of Water Survival course drill rescues with their classmates at the Marine Corps Base Hawaii pool, Dec. 12, 2014. A total of 18 Marines were tested this week. (U.S. Marine Corps photo by Christine Cabalo/Released)