EE WAS ROCKDUSTING THE UNIT. AS HE WAS PULLING THE DUSTER HOSE OUT OF A FACE HE STEPPED ON A PIECE OF TOP COAL THAT HAD FALLEN OUT. HIS FOOT SLIPPED OUT FROM UNDER HIM AND HE FELL ON HIS BACK. HE CONTINUED WORKING BUT STILL HAD PAIN IN HIS BACK. HE WENT FOR AN MRI ON 5/29/03, ON 5/30/03 HIS DR. INFORMED HIM OF A BULGED DISK & TOLD HIM TO TAKE OFF WORK STARTING THERAPY NEXT WEEK.