Derailment

MGRRV-01, WHILE PULLING TRAIN FORWARD IN WESTWARD DIRECTION TRAIN WENT INTO UNDESIRED EMERGENCY. THREE EMPTY AUTO RACKS WERE FOUND DERAILED MID TRAIN ON CURVE OF TURNOUT AT MP 559.26. TRAIN WAS TRAVERSING CURVE/TURNOUT APPROACHING 17/YARD 1 SWITCH. THE NORTH RAIL HAD MULTIPLE JOINTS AND WORN RAIL INA SHORT DISTANCE ON NORTH RAIL/LOW SIDE OF CURVE RESULTING IN ROLLED RAIL AT POINT OF DERAILMENT. CARS WERE RIDING ON WORN RAIL AND TIGHT GAGE WITH MULTIPLE JOINT BARS IN CLOSE PROXIMITY AND WHEELS IMPACTING JOINT BARS AND WHEELS IMPACTING JOINT BARS. RAIL CONDITION WORN WITH OVERFLOW AND BATTEREDJOINTS. RAIL JOINT ALSO HAD PREVIOUS BREAK AND CHIPPED ENDS IN CONJUNCTION WITH MINOR TO INTERMEDIATE PLATE CUT IN AREA WERE RAIL ROLLED.