CHEVRON PIPE LINE CO

Incident Narrative

IN EARLY MARCH 2022, A THIRD-PARTY OPERATOR INSTALLED A BLIND FLANGE WITH THREADED NIPPLE ON THE SOUTH TIMBALIER 52A PIPELINE TO DISCONNECT THEIR THIRD-PARTY PIPELINE FROM THE SYSTEM. AT SOME POINT DURING THEIR INSTALLATION OR DEMOBILIZATION FROM THE SITE, A NIPPLE ON THE BLIND FLANGE WAS DAMAGED. BECAUSE THE PIPELINE WAS TO BE DE-OILED SHORTLY THEREAFTER, NO STANDUP TEST OF THE NEWLY INSTALLED BLIND FLANGE WAS PERFORMED AT THAT TIME. AT APPROXIMATELY 15:00 ON 17 MAR 22, WHILE IN THE PROCESS OF PERFORMING STAND-UP TESTING IN PREPARATION TO DE-OIL THE SOUTH TIMBALIER 52 A PIPELINE CHEVRON PIPE LINE COMPANY (CPL) BEGAN PRESSURIZING THE PIPELINE. WHEN THE PIPELINE WAS UNABLE TO ACHIEVE THE TARGET PRESSURE, CPL CLOSED VALVE SDV7251 AT ST52 AND BEGAN PULLING A VACUUM ON THE LINE AT FOURCHON TERMINAL AT 15:20 ON 17 MAR 22. AN OVERFLIGHT OF THE AREA IDENTIFIED A SHEEN NEAR THE LOCATION OF THE DISCONNECTED ST34 TIE-IN AT 15:15 ON 17 MAR 22. AN OSRO WAS CALLED TO MOBILIZE TO THE AREA AND ARRIVED ON 17 MAR 22 AT 21:30. THE OSRO COULD NOT LOCATE THE SHEEN USING THEIR DETECTION EQUIPMENT AND DEMOBILIZED FROM THE AREA AT APPROXIMATELY 01:00 ON 18 MAR 22 DUE TO DECLINING WEATHER CONDITIONS. FINAL SPILL VOLUME CALCULATIONS WERE PERFORMED BASED ON PHOTOGRAPHS RECEIVED FROM LOSCO NEAR THE TIME OF THE RELEASE. AN ESTIMATED VOLUME OF 1.29 BARRELS WAS RELEASED INTO THE GULF OF MEXICO. A VACUUM WAS MAINTAINED ON THE LINE UNTIL A DIVE OPERATION COULD BE MOBILIZED ON 26 MARCH 22 TO INSPECT THE LINE. ON MARCH 26TH CPL REPAIRED THE DAMAGED NIPPLE THAT WAS CONFIRMED TO BE THE SOURCE OF THE RELEASE AND THE NIPPLE WAS REMOVED AND REPLACED WITH A BLIND FLANGE.