THE PLANT HAD SUSTAINED A POWER OUTAGE THE EVENING OF 10/2/02. THE NORMAL LIGHTING CIRCUIT FOR THE TUNNEL WAS WITHOUT POWER WHEN EE REPORTED TO WORK. THE EMERGENCY LIGHT AT THE CRUSHING PLANT OFFICE WAS WORKING. EE TRIPPED & FELL WHEN HE WALKED INTO A PORTABLE WELDER AT THE RIB OF #6 SYSTEM #19GH.