SOUTH BOW INFRASTRUCTURE OPERATIONS INC.

Incident Narrative

"AUGUST 28, 2025 - A ROOT CAUSE ANALYSIS IDENTIFIED THAT THE EXISTING PROCEDURE WAS NOT FOLLOWED AND THAT A UNIT PIPING DRAIN VALVE HAD NOT BEEN PLACED IN ITS NORMAL (CLOSED) POSITION PRIOR TO RE-FILLING THE UNIT PIPING. DURING RE-FILLING OF THE UNIT PIPING, PRODUCT PASSING THROUGH THE OPEN UNIT PIPING DRAIN VALVE OVERCAME THE CAPACITY OF THE DRAIN SYSTEM AND PRODUCT OVERFLOWED THROUGH THE PUMP SEAL DRAIN PIPING. ACTIONS IDENTIFIED FROM THE ROOT CAUSE INCLUDE; ENSURE ADEQUATE SPILL SUPPLIES ARE IN STOCK AT EACH STATION, REVIEW THE INCIDENT WITH WORKER AND CONDUCTING A REFRESH OF APPLICABLE TRAINING, SUSPENSION OF WORKER'S APPLICABLE OPERATOR QUALIFICATION TASK REQUIRING RECERTIFICATION, WORKER RETRAINING OF LOCK OUT TAG OUT, FEEDBACK AND REVIEW OF PROCEDURE ON REFILLING UNIT PIPING, AND SHARING LEARNINGS WITH COMPANY PERSONNEL. ON JUNE 4, 2025, LOCAL OPERATOR PERSONNEL HAD COMPLETED THE REMOVAL AND REPLACEMENT OF A DRAIN LINE VALVE. AT THE TIME OF THE RELEASE, THE PUMP UNIT-PIPING WAS BEING RE-FILLED WHEN CRUDE WAS WITNESSED LEAKING FROM THE PUMP SEALS. AN EMERGENCY SHUTDOWN WAS INITIATED IMMEDIATELY AND ALL WORK STOPPED FOR A SAFETY STAND-DOWN. LEADERS WERE INFORMED AND INTERNAL STAKEHOLDERS CONTACTED TO INITIATE A SPILL RESPONSE. UPON INITIAL REVIEW, A DRAIN VALVE WAS NOTED AS NOT BEING IN THE PROPER POSITION OVERWHELMING THE DRAIN LINES AND POTENTIALLY CONTRIBUTING TO THE LEAK. THIS WAS CORRECTED AND OPERATOR PERSONNEL COMPLETED FILLING THE PUMP UNIT PIPING AND BRINGING THE STATION BACK ONLINE. AN OSRO WAS CONTACTED TO ASSIST IN CLEANUP. THIS EVENT WAS ENTERED INTO THE INTERNAL INCIDENT MANAGEMENT TOOL AND A ROOT CAUSE ANALYSIS WAS INITIATED. WHILE THE VOLUME SPILLED DID NOT EXCEED THE REPORTING THRESHOLD IT WAS ASSUMED THAT THE ACQUISITION OF AN OSRO WOULD LIKELY EXCEED THE REPORTING THRESHOLD FOR DAMAGES."