EE STATED THAT HE WAS PREPARING TO DRILL A RIB BOLT HOLE. HE STATED THAT HE POSITIONED MAST OILDRILL STEEL IN IT TOWARD RIB, A 2 FOOT BOLT WRENCH WAS EXPELLED FROM DRILL STEEL TRAY, STICKING EE ACROSS CHEST. UNKOWINGLY THE WRENCH HAD BEEN FOULED IN THE TRAY.