SUNOCO PIPELINE L.P.

Incident Narrative

ON MARCH 28, 2023 AT APPROXIMATELY 08:52, DURING A STATION CHECK THE OPERATOR DISCOVERED A RELEASE COMING FROM THE TANK 2598 MIXER AREA. APPROXIMATELY 1094 BARRELS OF CRUDE OIL WAS RELEASED TO CONTAINMENT AND APPROXIMATELY 25 BARRELS OF THE TOTAL VOLUME MIGRATED OFF OPERATOR PROPERTY AND REACHED MESQUITE BRANCH CREEK. THE TANK IMPOUNDMENT DIKE DRAIN VALVE WAS IN THE CLOSED POSITION. HOWEVER, DUE TO DEBRIS IN THE VALVE BODY THE VALVE WAS NOT FULLY SEATED WHICH ALLOWED PRODUCT TO LEAK BY. BOOM WAS PLACED IN THE CREEK TO PREVENT FURTHER MIGRATION AND OSROS WERE DISPATCHED TO COLLECT FREE PRODUCT. CONTAMINATED SOIL FROM THE IMPOUNDMENT DIKE WAS REMOVED AND CLEAN FILL WAS BROUGHT IN. AN INVESTIGATION DETERMINED THE MIXER SEAL FAILED DUE TO A MIXER BEARING FAILURE. THE FAILED SEAL AND TANK MIXER WILL BE REPLACED AND THE ORIGINAL MIXER WILL BE SENT TO THE MANUFACTURER (PHILADELPHIA) FOR FAILURE ANALYSIS AND REBUILD. ADDITIONAL PREVENTATIVE MEASURES ARE EXPECTED TO BE DETERMINED FOR THIS MODEL OF MIXER POST ANALYSIS. SUPPLEMENTAL REPORT WILL BE FILED AFTER ANALYSIS IS COMPLETE. SUPPLEMENTAL & FINAL REPORT: UPDATED TOTAL COSTS AND CHANGED FUNCTION OF PIPELINE SYSTEM TO >20% SMYS REGULATED TRANSMISSION. A REPLACEMENT TANK MIXER WAS INSTALLED AND THE FAILED UNIT IS BEING RECONDITIONED. A REPRESENTATIVE FROM THE MIXER MANUFACTURER MADE A SITE VISIT TO EXAMINE THE FAILED MIXER AND CONFIRMED THE CAUSE OF THE FAILURE WAS A MIXER SEAL FAILURE DUE TO A BEARING FAILURE ON THE MIXER WHICH ALLOWED THE SHAFT TO DROP LEADING TO THE SEAL FAILURE.