Q63409 WAS INSTRUCTED TO TRIPLE UP TRAIN P1 TO P13 TO P01. CREW CAME OUT OF TRACK P03 ENGINES LIGHTAND RECEIVED PERMISSION FROM THE Y19110 INTO THE ZONE TO MAKE THEIR MOVES. Q63409 CONDUCTOR DOUBLEDP10 TO P13 THEN LINED THE UPPER CROSSOVERS FOR TRAINS MOVEMENT TO TRACK P01. Q63409 CONDUCTOR ALSO THREW THE PLUG SWITCH WHICH WAS NOT NEEDED FOR THE Q63409 MOVE. AFTER CLEARING ON TRACK P01 Q63409 CONDUCTOR REPORTED CLEAR OF THE Y19110 ZONE WITH UPPER CROSSOVERS RESTORED FOR MOVEMENT. Y19110 PULLED62 CARS WEST FROM TRACK P20 AT THE TIME LOCOMOTIVE RAN THRU THE PLUG SWITCH WHICH Q63409 CONDUCTORLINED AGAINST THE Y19009. Y19110 MADE CUT ON CARS AND PULLED TO CLEAR TRACK P14 THEN SHOVED, DERAILING 8 CARS AT THE RUN THRU SWITCH.