AN IGNITION OCCURRED IN THE FACE OF NO.2 ENTRY 214 FT INBY CENTER LINE OF NO. 21 X CUT ON 5 NORTH SECTION MMU 028-0. NO INJURIES OR PROPERTY DAMAGE WAS SUSTAINED. THE FLAME LASTED 2 SECS. AND SIZE WAS 4"" BALL-SELF-EXTINGUISHING. IGNITION OCCURRED LEFT SIDE OF FACE 2 FT INBY TUBES A DAY VEIN HAD JUST RAN OUT IN RIGHT CORNER OF FACE.