ANR PIPELINE CO — Gas transmission and gathering — incident on 2014-07-26

Gas transmission and gathering incident. Reported cause: CORROSION FAILURE. Reported consequences: 0 fatalities, 0 injuries, 1 NATURAL GAS released, $235,000 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: 20140091.

Operator ID: 405.

Reported incident date: 7/26/2014 17:38.

Cause detail: INTERNAL CORROSION

Cause detail: ON 26 JULY 2014, A THIRD-PARTY HELICOPTER PATROL OBSERVED A RELEASE OF GAS LOCATED IN WEST CAMERON BLOCK 165 (29.37260800, -93.54129500) SOUTH OF CAMERON PARISH IN THE GULF OF MEXICO. THE LEAK WAS REPORTED TO ANR PIPELINE COMPANY, OPERATOR FOR TC OFFSHORE, AS AN APPROXIMATELY TEN FOOT IN DIAMETER BUBBLING OVER THE LOCATION OF TC OFFSHORE'S 687 TRANSMISSION PIPELINE. THE SECTION OF 687 LINE CONTAINING THE LEAK WAS SHUT IN BY A CHECK VALVE ON THE DOWNSTREAM SIDE AND BY CLOSING A VALVE ON THE UPSTREAM SIDE. NO SHEEN OR PRODUCT WAS REPORTED AT THE SURFACE OF THE WATER. FOLLOWING THE SECTION BEING SHUT IN, CONTRACT EMPLOYEES WERE DEPLOYED TO THE SITE TO INVESTIGATE AND REPAIR THE LEAK. PRIOR TO THE ARRIVAL OF THE CONTRACTORS, HELICOPTER PATROLS WERE CONDUCTED IN THE AREA TO MONITOR THE LEAK AND CONDITIONS OF THE SITE. NO SHEEN OR PRODUCT WAS REPORTED FOR THE DURATION OF AERIAL MONITORING WHILE THE PIPELINE WAS BEING REPAIRED. ON 29 JULY, ANR AND CONTRACT PERSONNEL FROM CAL-DIVE INTERNATIONAL ARRIVED AT THE LEAK LOCATION IN WEST CAMERON BLOCK 165 TO INSPECT THE PIPE AND REPAIR THE LEAK. AT APPROXIMATELY 12:00 CDT, DIVERS ENTERED THE WATER AND DETERMINED THE LOCATION OF THE LEAK. AFTER DETERMINING THE APPROXIMATE LOCATION OF THE LEAK, PIPELINE PRESSURE WAS REDUCED TO 80 PSIG WATER, AND WATER BLASTING WAS USED TO REMOVE THE CONCRETE COATING FROM THE PIPE TO PREPARE FOR THE INSTALLATION OF A PLIDCO TEN INCH BOLT-ON CLAMP OVER THE LEAK. THE CLAMP WAS THEN INSTALLED ACCORDING TO MANUFACTURER SPECIFICATIONS, THE EXPOSED PIPE WRAPPED IN SYNTHO-GLASS, AND PIPELINE BACKFILLED. FINALLY, THE PIPELINE WAS MONITORED DURING REPRESSURIZATION TO CONFIRM THAT THE LEAK WAS SUCESSFULLY REPAIRED.

PHMSA trend classification: significant incident, not serious.

PHMSA standardized cause: CORROSION — INTERNAL.

PHMSA indexed costs: $243,734 reported total cost, $125,285.165 in 1984 dollars, $301,077.988 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.