TRANSCONTINENTAL GAS PIPE LINE COMPANY — Gas transmission and gathering — incident on 2013-12-31

Gas transmission and gathering incident. Reported cause: EQUIPMENT FAILURE. Reported consequences: 0 fatalities, 0 injuries, 25 NATURAL GAS released, $250,000 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: 20140011.

Operator ID: 19570.

Reported incident date: 12/31/2013 10:30.

Cause detail: THREADED CONNECTION/COUPLING FAILURE

Cause detail: ON 12-31-13, AT 10:30 AM CST, AN OFFSHORE VESSEL CONTRACTED BY PRODUCER, ERT, STATIONED AT NEARBY SMI 130-A PLATFORM REPORTED TO WILLIAMS SCHRIEVER DISTRICT OFFICE THAT THEY SITED BUBBLES WITH NO SHEEN ON THE SURFACE OF THE WATER. WILLIAMS OPERATIONS DISPATCHED A HELICOPTER TO INVESTIGATE THE REPORT. THE HELICOPTER CONFIRMED BUBBLES AT THE SAME COORDINATES GIVEN BY THE VESSEL. THE COORDINATES WERE PLOTTED ON ALIGNMENTS SHEETS, THE SUPPORTING DATA SOURCE WAS BSEE'S OWL PROGRAM. AS INDICATED, THERE WERE BUBBLES IN THE VICINITY OF THE WILLIAMS PIPELINE AND A PRODUCER LINE. DUE TO ROUGH SEAS AND WEATHER CONDITIONS WILLIAMS COULD NOT SEND A DIVE BOAT TO CONFIRM THAT THE BUBBLES WERE COMING FROM ITS PIPELINE. IN THE MEANTIME, OPERATIONS MADE A DECISION TO ISOLATE THE WILLIAMS PIPELINE, SUSPEND GAS RECEIPTS INTO THE LINE AND LOWER THE PRESSURE ON THE PIPELINE. AT 7:55 AM CST, ON 1-6-14, EVENTUALLY WEATHER CONDITIONS PERMITTED THE FLYOVER OF THE LEAK AREA AND OPERATIONS WAS ABLE TO CONFIRM THAT THE LEAK WAS COMING FROM THE WILLIAMS PIPELINE. AT 9:50 AM CST GAS CONTROL NOTIFIED THE NRC. A DIVE BOAT WAS SENT TO THE LEAK LOCATION AND THE SOURCE OF THE GAS LEAK WAS IDENTIFIED AS A 1/2-INCH THREADED SWIVEL CONNECTOR ON A SUBSEA ASSEMBLY. THE CONNECTOR WAS REPLACED, THE PIPELINE WAS PRESSURED UP AND PUT BACK INTO SERVICE ON 1-30-14 AT 9:22 PM CST.

PHMSA trend classification: significant incident, not serious.

PHMSA standardized cause: EQUIPMENT FAILURE — THREADED CONNECTION/COUPLING FAILURE.

PHMSA indexed costs: $282,683 reported total cost, $150,211.488 in 1984 dollars, $356,248.299 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.