EE WAS RIDING IN THE BUCKET OF A SCOOP USED FOR MANTRIP. EDGE OF SCOOP BUCKET CAUGHT AN OLD ROOF BOLT LYING ON MINE FLOOR, CAUSING IT TO FLIP UP & STRIKE EE ON HIS HEAD BEHIND HIS LEFT EAR. EE WORKED UNTIL 7:00 P.M., THEN CAME OUTSIDE AND TRANSPORTED TO E.R. HE WAS TREATED AND RELEASED FOR A BRUISE.