GULF SOUTH PIPELINE COMPANY, LLC

Incident Narrative

WHILE TRACKING AN INLINE INSPECTION TOOL ON 10/25/2023, GULF SOUTH PERSONNEL IDENTIFIED A LEAK ON ITS INDEX 129 PIPELINE. GULF SOUTH ISOLATED APPROXIMATELY 13 MILES OF PIPELINE AND UTILIZED FLARES TO BLOW DOWN THE PIPELINE IN ORDER TO MAKE REPAIRS. A 16' PIECE OF REPLACEMENT PIPE WAS INSTALLED ON 10/28/2023 AND THE PIPELINE WAS RETURNED TO NORMAL SERVICE THAT EVENING. THE INCIDENT CAUSE IS CURRENTLY UNDER INVESTINGATION AND A SUPPLEMENTAL REPORT WILL BE SUBMITTED WHEN THE CAUSE HAS BEEN DETERMINED. 3/7/2024 UPDATED PARTS G AND J AND SUBMITTED FINAL REPORT. THE ROOT CAUSE INVESTIGATION REVEALED THE FOLLOWING: THE INSTALLED REINFORCEMENT SADDLE (INSTALLATION DATE UNKNOWN) WAS NOT PROPERLY FITTED AND WAS ATTACHED WITH AN INSUFFICIENT SINGLE-PASS FILLET WELD TO BOTH THE PIPELINE AND TO THE CENTRAL BRANCH PIPE. THESE WELDS ARE NOT SUFFICIENT TO PROPERLY ATTACH THIS REINFORCEMENT SADDLE. MOVEMENT OF THE BRANCH WITH ALL ATTACHED FLANGES, VALVE, AND PIPING CAUSED A DUCTILE OVERLOAD FAILURE OF THE PIPE WALL THAT INITIATED AT THE TOE OF THE REINFORCING SADDLE TO PIPELINE WELD AND PROCEEDED THROUGH-WALL IN TWO OR MORE STEPS. NO EVIDENCE OF FATIGUE WAS OBSERVED.