TEXAS EASTERN TRANSMISSION, LP (SPECTRA ENERGY PARTNERS, LP)

Incident Narrative

ON JULY 10, 2021 AT 3:50 P.M. CST, A HELICOPTER PILOT DISCOVERED BUBBLES IN THE GULF OF MEXICO. AT THAT TIME TETLP COULD NOT CONFIRM THAT IT WAS A TETLP ACTIVE LINE IN THE VICINITY. AFTER PRELIMINARY INVESTIGATION AND DISCUSSION WITH FIELD OPERATIONS, TETLP MADE THE NOTIFICATION TO THE NRC AT 5:26 P.M. CST BASED REPAIR COSTS THAT WOULD EXCEED THE DOLLAR THRESHOLD FOR REPORTING ASSUMING THE LEAK WAS ON TETLP'S SYSTEM. DUE TO LIMITED CONTRACTOR AVAILABILITY IN THE GULF COAST REGION, A DIVING VESSEL CONTRACTOR COULD NOT START MOBILIZING TO THE BUBBLE SITE UNTIL JULY 14, 2021. AT APPROXIMATELY 4:30 PM CST ON JULY 16, 2021 IT WAS CONFIRMED THAT THE LEAK WAS ON TETLP'S LINE 40-B-4. THE LINE 40-B-4 WAS TAKEN OUT OF SERVICE ON JULY 16, 2021; REPAIR WAS COMPLETED ON AUGUST 12, 2021 BY INSTALLING A MECHANICAL COUPLING AND THE LINE WAS RESTARTED AUGUST 12 AT 2:45 P.M. CST. THE LEAK WAS A PIN HOLE IN THE PIPE WALL CAUSED BY INTERNAL CORROSION AT THE 6 O'CLOCK POSITION. THE ROOT CAUSE IS BELIEVED TO BE DUE TO A MIX OF GAS, WATER AND CONDENSATE TRANSPORTED ON THIS PIPELINE SYSTEM.