U.S. Marines pick up trash as voluntary community service in support of exercise Ssang Yong 14 at Ocheon Stream in Pohang, South Korea, March 28, 2014. Marine Expeditionary Force Exercise (MEFEX) 2014 was a U.S. Marine Corps Forces Pacific-sponsored series of exercises between the U.S. Navy and Marine Corps and South Korean forces. Among the exercises were the Korea Marine Exercise Program, Freedom Banner 14, Ssang Yong 14, Key Resolve 14 and the Combined Marine Component Command 14 command post exercise.