EE WAS RECOVERING BELT STRUCTURE FROM THE OLD WORKS ON #3 UNIT AT THE TIME OF THIS INCIDENT. A MANTRIP IN THIS AREA WAS STUCK IN MUD. THEY USED A SCOOP TO PULL THE MANTRIP OUT OF THE MUD. CO- WORKER WAS DRIVING THE SCOOP AND AS EE WENT TO UNHOOK THE CHAIN BETWEEN THE SCOOP & MANTRIP THESCOOP ROLLED FORWARD CATCHING EE'S HAND BETWEEN THE BUMPER OF MANTRIP & THE SCOOP BUCKET.