THE DRILLER HAD COMPLETED DRILLING A HOLE AND WAS REMOVING THE DRILL STEEL FROM THE HOLE. HE WAS USING HIS ROD CHANGER TO PLACE A STEEL BAR BACK INTO THE RACK AD WHILE HE WAS DOING THIS THE RE MAINING STEEL SLID THRU THE CENTRALIZER AND FELLBACK DOWN THE HOLE. THE DRILLER TRIED TO RETRIEVE THE STEEL WITH ANOTHER STEEL ROD BUT THAT ONE ALSO FELL DOWN INTO THE HOLE. HE THEN TOOK A SH