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

Incident Narrative

ORIGINAL REPORT: ORIGINAL NRC # 1253844 48 HOUR REPORT NRC # 1254075 AT APPROXIMATELY 1:23 A.M. EDT ON AUGUST 1, 2019, TETLP'S 30-INCH DIAMETER LINE 15 TRANSPORTING NATURAL GAS FROM DANVILLE COMPRESSOR STATION TO TOMPKINSVILLE COMPRESSOR STATION IN KENTUCKY FAILED AT MP 423.4. THE FAILURE RESULTED IN AN EXPLOSION AND FIRE. TETLP GAS CONTROL RECEIVED A RATE OF CHANGE ALARM ON LINE 15 ON THE SOUTH SIDE OF DANVILLE COMPRESSOR STATION AT APPROXIMATELY 1:25 AM EDT. DURING THE ENSUING MINUTES, TETLP BEGAN RECEIVING REPORTS FROM THE PUBLIC AND A TETLP OPERATOR OF A FIRE SOUTH OF THE DANVILLE COMPRESSOR STATION. TETLP PERSONNEL WERE IMMEDIATELY DISPATCHED TO CLOSE MAINLINE BLOCK VALVES, MLV 15-382 AT MP 408.48 AND MLV 15-393 AT THE DANVILLE COMPRESSOR STATION, THUS ISOLATING THE FAILED SEGMENT. FIRST RESPONDERS EVACUATED APPROXIMATELY 75 MEMBERS OF THE PUBLIC. THE INCIDENT RESULTED IN 1 FATALITY AND 6 KNOWN INJURIES. 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. ALSO NOTE THE PIPE INVOLVED IN THE INCIDENT WAS MANUFACTURED IN 1957 AND INSTALLED IN 1958, AS REFLECTED IN PART C, ITEM 3G OF THIS REPORT. THE PHMSA CORRECTIVE ACTION ORDER INCORRECTLY STATED THE PIPE WAS INSTALLED IN 1942. SUPPLEMENTAL REPORT - 7/21/2020 UPDATED PART A.7 ESTIMATED VOLUME OF GAS RELEASED UNINTENTIONALLY TO 101,485 MCF UPDATED PART A.8 ESTIMATED VOLUME OF INTENTIONAL AND CONTROLLED RELEASE/BLOWDOWN TO 25,918 MCF UPDATED ADDITIONAL PARTS AS A RESULT OF CHANGES TO THE PHMSA PORTAL SUPPLEMENTAL FINAL REPORT -11/20/2022 UPDATED PART A 16.B DATE AND TIME THE LINE RESTARTED UPDATED PART G 5. POST-CONSTRUCTION PRESSURE TEST VALUE. THE NTSB DETERMINED THE PROBABLE CAUSE OF THE AUGUST 1, 2019, ENBRIDGE INC. PIPELINE RUPTURE AND RESULTING FIRE WAS THE COMBINATION OF A PRE-EXISTING HARD SPOT (A MANUFACTURING DEFECT), DEGRADED COATING, AND INEFFECTIVE CATHODIC PROTECTION APPLIED FOLLOWING A 2014 GAS FLOW REVERSAL PROJECT, WHICH RESULTED IN HYDROGEN INDUCED CRACKING AT THE OUTER SURFACE OF LINE 15 AND THE SUBSEQUENT FAILURE OF THE PIPELINE.