COLUMBIA GULF TRANSMISSION, LLC — Gas transmission and gathering — incident on 2015-05-21

Gas transmission and gathering incident in RAYNE, ACADIA PARRISH County, LA. Reported cause: EQUIPMENT FAILURE. Reported consequences: 0 fatalities, 0 injuries, 34860 NATURAL GAS released, $20,000 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: 20150082.

Operator ID: 2620.

Reported incident date: 5/21/2015 21:47.

Location detail: RAYNE

Cause detail: OTHER EQUIPMENT FAILURE

Cause detail: ON MAY 21, 2015, COLUMBIA GULF TRANSMISSION, LLC (COLUMBIA) RECEIVED AN ALARM FROM RAYNE COMPRESSOR STATION (CS) FACILITY REGARDING AN EMERGENCY SHUTDOWN (ESD). COLUMBIA PERSONNEL WERE DISPATCHED TO INVESTIGATE THIS ALARM. UPON ARRIVING AT THE SITE, COLUMBIA PERSONNEL NOTED THAT THE FACILITY WAS IN AN ESD MODE AND MATERIAL WAS STILL VENTING INADVERTENTLY INTO ATMOSPHERE. THE FACILITY WAS INSPECTED TO IDENTIFY THE LOCATION OF THE OPEN VALVE IN ORDER TO ACT ACCORDINGLY. THE COLUMBIA PERSONNEL DISCOVERED AN 8-IN ESD VALVE IN THE OPEN POSITION. COLUMBIA PERSONNEL ASKED FOR ASSISTANCE TO MANUALLY OVER-RIDE THIS VALVE. AFTER 21 MINUTES, THE VALVE STOPPED FLOWING MATERIAL AND THE FACILITY WAS PUT INTO SAFE OPERATION. FOLLOWING THE INCIDENT, COLUMBIA ASSEMBLED AN INVESTIGATIVE TEAM FROM COMPRESSION, AUTOMATION AND ELECTRICAL GROUPS IN ADDITION TO THE VALVE MANUFACTURER, IN ORDER TO INVESTIGATE AND HELP ASSEMBLE THE CHAIN OF EVENTS THAT LED THIS 8-IN ESD VALVE FROM FAILING TO CLOSE. PRELIMINARY INDICATIONS FOCUSED ON A SOFTWARE GLITCH WHICH LED TO INITIATE THIS ESD EVENT AND FALSE SIGNAL BY THE CONTROL PROCESSING UNIT TO INITIATE PROPER SIGNALS TO STOP THE MATERIAL FROM FLOWING INADVERTENTLY INTO ATMOSPHERE. THE FAULTY VALVE WAS ISOLATED AND WAS NOT RETURNED BACK INTO SERVICE UNTIL AN INVESTIGATION WAS COMPLETED TO ENSURE THAT THAT THE SAME HARDWARE ERROR WILL NOT TRIGGER ANOTHER EVENT. THE ESD SYSTEM WAS RETURNED BACK INTO SERVICE ON JUNE 12, 2015. DURING THIS TIME, THE CS WAS MANNED. THE KEY LESSONS IDENTIFIED FROM THIS INCIDENT WAS THAT COLUMBIA PERSONNEL TO ASSURE QUARTER TURN VALVES ARE IN THE OPEN POSITION AFTER ANY VALVE MAINTENANCE IS PERFORMED AND TO PERIODICALLY CHECK THE CENTRAL PROCESSING UNIT AREA FOR ANY FUTURE SIGNS OF TAMPERING OR EVIDENCE OF RODENTS. INITIAL INCIDENT REPORT WAS SUBMITTED ON JUNE 18, 2015

PHMSA trend classification: significant incident, not serious.

PHMSA standardized cause: EQUIPMENT FAILURE — OTHER EQUIPMENT FAILURE.

PHMSA indexed costs: $105,407 reported total cost, $89,225.273 in 1984 dollars, $121,944.689 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.