Sergeant Zepp was a member of Company F, 2nd Battalion, 31st Infantry Regiment, 7th Infantry Division. He was seriously wounded by the enemy in North Korea on 30 October 1952 and returned to duty on 1 November 1952. He was listed as Missing in Action while fighting the enemy in North Korea on 12 January 1953. He was presumed dead on 13 January 1954. His remains were not recovered. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

Zepp was awarded the Purple Heart with Oak Leaf Cluster, the Combat Infantryman Badge, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.