EE WAS OPERATING THE TANKHOUSE STRIPPER CRANE HARVESTING CATHODE. WHEN THE EE PLUGGED CRANE, THE POWER TO THE CRANE TRIPPED OUT. EE TRIED TO RESET THE POWER, BUT COULD NOT. THE CRANE FORCEFULL Y HIT THE CRANE STOP ON THE NORTH END OF THE BUILDING. THIS RESULTED IN DAMAGE TO THE CRANE STOPS AND JARRED THE OPERATOR INSIDE THE CRANE. EE SUSTAINED A LOWER BACK STRAIN.