He returned for a second operational tour to South Vietnam with the 5th Battalion On 28 January 1969.
On 25 April 1969, during Operation Surfside in Phuoc Tuy Province, Corporal Mundine was the leading Section Commander 'with 1 Platoon, A Company. On approaching a suspected enemy area, Corporal Mundine deployed his section on the ground and moved forward alone to reconnoitre the enemy position.
He sighted enemy bunkers and was about to signal further instructions when he detonated a mine which severed his lower right leg and caused severe wounds to his back and his other leg. Members of his section started to move forward to his assistance into what was later shown to be an enemy minefield.
Corporal Mundine, although in considerable pain, ordered his section to stay out of the area and directed them to new fire positions after giving full details of the enemy bunker system. For over forty minutes he continued to give instructions to his section and refused to allow any members of the platoon to move near him until engineers had cleared path through the minefield.
This occasion was typical of the outstanding leadership and complete disregard for his own safety that Corporal Mundine has shown through three months of operational service.