WILLIAMS GAS PIPELINE - TRANSCO — Gas transmission and gathering — incident on 2011-12-03

Gas transmission and gathering incident in SWEETWATER, MARENGO County, AL. Reported cause: CORROSION FAILURE. Reported consequences: 0 fatalities, 0 injuries, 61700 NATURAL GAS released, $6,961,000 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: 20110392.

Operator ID: 19570.

Reported incident date: 12/3/2011 15:07.

Location detail: 817.77

Cause detail: EXTERNAL CORROSION

Cause detail: ON SATURDAY, DECEMBER 3, 2011, TRANSCO EXPERIENCED A RUPTURE ON ITS 36 INCH MAINLINE C APPROXIMATELY 7 MILES DOWNSTREAM OF STATION 90 NEAR LINDEN, AL. THE RUPTURE DID IGNITE, HOWEVER THERE WERE NO INJURIES. THERE WAS APPROXIMATELY 8 ACRES OF FORESTED AREA BURNED. OPERATIONS PERSONNEL RESPONDED AND HAD THE SEGMENT ISOLATED WITHIN 45 MINUTES OF THE RUPTURE. MAINLINE B WAS PARTIALLY EXPOSED BY THE RUPTURE AND WAS TAKEN OUT OF SERVICE AND PHMSA ORDERED THAT THE ADJACENT MAINLINES (MAINLINES A, D, AND E) BE OPERATED WITH A 20% REDUCTION IN PRESSURE. A SUBSEQUENT CONFERENCE CALL WITH PHMSA ON MONDAY, DECEMBER 5TH, 2011, RESULTED IN PHMSA ALLOWING WGP TO OPERATE MAINLINES 30 INCH A, 36 INCH D, AND 42 INCH E WITHOUT ANY PRESSURE LIMITATIONS. A ROOT CAUSE ANALYSIS WAS COMPLETED AND APPROVED BY PHMSA. THE CAUSE OF THE ACCIDENT WAS DUE TO EXTERNAL CORROSION.

PHMSA trend classification: significant incident, not serious.

PHMSA standardized cause: CORROSION — EXTERNAL.

PHMSA indexed costs: $7,658,770 reported total cost, $4,121,492.088 in 1984 dollars, $10,078,257.539 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.