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

Incident Narrative

AT APPROXIMATELY 4:36 PM EDT ON MAY 4, 2020, TETLP'S 30-INCH DIAMETER LINE 10 TRANSPORTING NATURAL GAS FROM WHEELERSBURG COMPRESSOR STATION TO OWINGSVILLE COMPRESSOR STATION IN KENTUCKY FAILED AT M.P. 509.898. THE FAILURE RESULTED IN AN EXPLOSION AND FIRE. TETLP RECEIVED A CALL ATTENDANT ALARM AT 4:39 PM EDT FROM THE OWINGSVILLE COMPRESSOR STATION. DURING THE ENSUING MINUTES, TETLP BEGAN RECEIVING REPORTS FROM THE PUBLIC OF A FIRE NORTH OF THE OWINGSVILLE COMPRESSOR STATION. TETLP PERSONNEL WERE IMMEDIATELY DISPATCHED TO CLOSE MAINLINE BLOCK VALVE, MLV 10-367 AT MP 517 AND MLV 10-351 AT THE OWINGSVILLE COMPRESSOR STATION, THUS ISOLATING THE FAILED SEGMENT AT 5:23 EDT. TETLP INITIATED THE NOTIFICATION TO THE NRC AT 5:23 PM EDT AFTER RECEIVING CONFIRMED DISCOVERY OF THE PIPELINE FAILURE AND GATHERING THE INITIAL INFORMATION TO MAKE THE NRC NOTIFICATION WITH THE CALL TERMINATING AT 5:40 PM EDT. NOTE THAT THE NRC RECORDS THE TIME THE CALL WAS TERMINATED ON THE NRC REPORT AND NOT THE TIME OF THE CALL WAS INITIATED. THE APPARENT CAUSE OF THE INCIDENT IS UNDER INVESTIGATION BY THE NTSB. THE INCIDENT CAUSE IS BEING REPORTED AS OTHER INCIDENT CAUSE UNTIL THE NTSB RELEASES INFORMATION ABOUT THE INCIDENT CAUSE. THE APPARENT CAUSE WILL BE UPDATED WHEN IT BECOMES AVAILABLE FROM THE NTSB. PART J WILL BE SUPPLEMENTED AS WELL ALONG WITH CAUSE. NOTE THAT E.1.A ESTIMATED GAS FLOW IN PIPE SEGMENT AT THE POINT AND TIME OF THE INCIDENT (MSCF/D): IS WAS APPROXIMATELY 1,433,000 DTH/D RATE THROUGH THE OWINGSVILLE COMPRESSOR STATION WHICH INCLUDES BOTH LINES 10 AND 25. LINE 15, WHICH SHARES THE RIGHT OF WAY WITH LINES 10 AND 25 WAS ISOLATED AT THE TIME OF THE INCIDENT. 11/15/2022 UPDATED PART C6 DATE PIPE MANUFACTURED UPDATED PART D7 ESTIMATED PROPERTY DAMAGE UPDATED PART E11 CONTROL ROOM INVESTIGATION UPDATED PART G APPARENT CAUSE TO NATURAL FORCE LANDSLIDE UPDATED PART H TO INCLUDE NTSB PROBABLE CAUSE ""THE NATIONAL TRANSPORTATION SAFETY BOARD DETERMINES THAT THE PROBABLE CAUSE OF THE PIPELINE RUPTURE WAS ENBRIDGE INC.'S ANALYSIS OF AN ACTIVE LANDSLIDE THAT DID NOT FULLY ADDRESS UNCERTAINTIES ASSOCIATED WITH PIPELINE DEFECTS, LANDSLIDE MOVEMENT, AND CORRESPONDING PIPELINE RESPONSE."" THE PIPELINE FAILURE INITIATED AT A CIRCUMFERENTIAL WELD JOINT.