ANR PIPELINE CO

Incident Narrative

ON 29 SEPTEMBER 2022, TC ENERGY TECHNICIANS WERE PERFORMING A CORRECTIVE WORK ORDER TO REPLACE THE HYDRAULIC FLUID IN THE 501-45A-34 VALVE. WHILE PERFORMING THE WORK, AN INCIDENT OCCURRED RESULTING IN INJURIES AND A RELEASE OF GAS. THE INCIDENT WAS REPORTED TO THE NATIONAL RESPONSE CENTER, #1348627. THE ANR 2-501 PIPELINE MP582.6 TO MP585.1 - 2-501 LOOP SOUTH END TO MAINLINE VALVE 46 (ISOLATED SEGMENT), HAS BEEN BLOWN DOWN AND ISOLATED. IN ADDITION, TC ENERGY HAS SUSPENDED QUALIFICATIONS ON COVERED TASKS ASSOCIATED WITH THE WORK BEING PERFORMED ASSOCIATED WITH THE INCIDENT AND CONDUCTED DRUG TESTING. THE PIPELINE SEGMENT REMAINED OUT OF SERVICE UNTIL REPAIR OF THE PIPELINE WAS COMPLETED. REPAIR TO THE PIPELINE INCLUDED THE REPLACEMENT OF THE VALVE AND VALVE OPERATOR. THE PIPELINE WAS RESTARTED AND RETURNED TO FULL SERVICE ON JANUARY 13, 2023 AT 11:39 CST. THE PRIMARY CAUSE OF THE FAILURE HAS BEEN DETERMINED TO BE THE RESULT OF THE TECHNICIAN FAILING TO CONFIRM MANUFACTURER'S REPAIR PROCEDURE AND OPENING THE VALVE DURING CORRECTIVE MAINTENANCE TO REPLACE THE HYDRAULIC HAND PUMP. FOLLOWING THE REPAIR, WHEN THE VALVE WAS ACTUATED USING THE HAND PUMP, HYDRAULIC OIL BEGAN TO MOVE TO THE OPEN SIDE OF THE VALVE STEM AND THE VALVE GATE DISENGAGED AND MOVED IN AN UNCONTROLLED MANNER. THE RESULT OF THIS ACTION CAUSED A FAILURE IN THE VALVE ACTUATOR CONNECTION AND A RELEASE OF PIPELINE FLUIDS AND HYDRAULIC OIL TO THE SURROUNDING AREA.