TRANSCONTINENTAL GAS PIPE LINE COMPANY — Gas transmission and gathering — incident on 2017-09-15

Gas transmission and gathering incident. Reported cause: CORROSION FAILURE. Reported consequences: 0 fatalities, 0 injuries, 709 NATURAL GAS released, $81,000 reported property damage. Operator-reported incident data submitted to PHMSA, generally within 30 days. Records may be supplemented or corrected and do not represent final agency causal findings.

Report number: 20170089.

Operator ID: 19570.

Reported incident date: 9/15/2017 19:00.

Cause detail: INTERNAL CORROSION

Cause detail: 9/11/2017 WGP WAS NOTIFIED BY THIRD PARTY THAT BUBBLES WERE PRESENT IN SHIP SHOAL BLOCK 158. 9/13/2017 OPERATIONS INVESTIGATED AND DETERMINED THAT BUBBLES WERE LIKELY COMING FROM THE WGP 10' PIPELINE. THE SECTION OF 10' PIPELINE WAS ISOLATED. 9/15/2017 A DIVE BOAT WAS DISPATCHED AND UPON ARRIVING ON SITE TO INVESTIGATE THE LEAK A SECOND SET OF BUBBLES WERE DISCOVERED. DIVERS INVESTIGATED AND DETERMINED THAT BOTH LEAKS WERE ON THE WGP 10' PIPELINE. THE PIPELINE PRESSURE WAS REDUCED AND CLAMPS WERE INSTALLED. THE FIRST LEAK OCCURRED AT M.P. 17.029 AND THE SECOND LEAK OCCURRED AT M.P. 17.444. 9/15/2017 IT WAS DETERMINED THAT THE COST OF THE RESPONSE AND THE REPAIR WOULD EXCEED THE $50K THRESHOLD. NRC WAS NOTIFIED. 9/28/2017 THE PIPELINE REMAINS IDLE WITH MINIMAL PRESSURE. OPERATIONS AND CYPRESS DIVISION ARE WORKING TO ABANDON THE LINE. 10/19/2017 AT THE REQUEST OF BRIAN PIERZINA, PHMSA AID, THIS REPORT HAS BEEN SPLIT INTO TWO SEPARATE REPORTS DUE TO THE FACT THAT THERE WERE TWO LEAKS. THIS SUPPLEMENTAL REPORT CORRESPONDS TO THE LEAK AT M.P. 17.029. GAS VOLUME REPORTED ABOVE IS THE BEST ESTIMATE FOR THAT LOCATION ONLY. 6/5/2018 AS OF THIS DATE, THERE HAS BEEN NO CHANGE TO THE OPERATIONAL STATUS OF THIS PIPELINE. IT REMAINS ISOLATED WITH MINIMAL PRESSURE. WE ARE WORKING WITH OUR PRODUCER PARTNERS AS WELL AS THE OTHER REGULATORY AGENCIES FOR APPROVAL TO ABANDON THE LINE. THE FINAL ABANDONMENT IS SLATED TO TAKE PLACE IN 3Q 2019. AT THE REQUEST OF BRIAN PIERZINA, WE HAVE UPDATED THE "FACILITY RESTART" DATE TO 9/15/2017 AS THAT WAS THE POINT IN WHICH ACTIVITIES ASSOCIATED WITH THE RELEASE EVENT WERE ESSENTIALLY CONCLUDED. THIS REPORT WILL NOW BE MARKED AS "FINAL".

PHMSA trend classification: not significant, not serious.

PHMSA standardized cause: CORROSION — INTERNAL.

PHMSA indexed costs: $88,335 reported total cost, $44,255.364 in 1984 dollars, $106,249.535 in current-year dollars.

PHMSA trend flags, standardized causes, and indexed costs are analytical fields added to operator-reported incident data. They do not represent final agency causal findings.