INJURED EE WAS RACKING THE KELLY BAR WHEN HE WAS STRUCK IN THE FACE BY A FLYING OBJECT, WHICH TEMPORARILY STUNNED HIM, CAUSING A DIAGONAL LACERATION REQUIRING APPROX. 25 STITCHES. DRILL WAS RE PORTED TO BE IDLING AT THE TIME OF INDIENT WITH WITH NO MOVING EQUIPMENT OTHER THAN THE ENGINE SUPPLYING POWER.