COLUMBIA GAS TRANSMISSION, LLC

Incident Narrative

ON AUGUST 25, 2016 AT 04: 25 AM, AN ALARM WAS ACKNOWLEDGED BY COLUMBIA GAS TRANSMISSION, LLC (COLUMBIA) GAS CONTROL (GC) PERSONNEL TRIGGERED FROM SMITHFIELD COMPRESSOR STATION (CS). FOLLOWING THE GC PROTOCOLS, OPERATIONS PERSONNEL WERE NOTIFIED TO INVESTIGATE THIS ALARM AT THE CS. SMITHFIELD CS (LOCATED IN WETZEL COUNTY, WEST VIRGINIA) IS A TRANSMISSION CS THAT IS OPERATED AND MAINTAINED BY COLUMBIA. UPON ARRIVING AT THE CS, COLUMBIA PERSONNEL IDENTIFIED THE SOURCE OF THE NOISE FROM THE RELEASED NATURAL GAS (MATERIAL) INTO ATMOSPHERE AND MANUALLY CLOSED THE PROPER VALVES ON SITE TO CONTROL THE MATERIAL RELEASE. DUE TO THE UNINTENDED RELEASE OF MATERIAL THAT EXCEEDED 3,000 MCF, IT WAS REPORTED TO THE NATIONAL RESPONSE CENTER AS AN INCIDENT. THE INVESTIGATION INTO THE PROBABLE CAUSE BEHIND THE EMERGENCY SHUTDOWN (ESD) ACTIVATION AT SMITHFIELD CS HAS BEEN TRACED TO A PROGRAMMABLE LOGIC CONTROLLER (PLC) ERROR THAT RESULTED IN A FAULTY SIGNAL TO THE PNEUMATIC SYSTEM, CAUSING THE ESD VENT VALVES TO OPEN. THE ESD SYSTEM WAS INSPECTED WITH ITS RESPECTIVE COMPONENTS AND THE CS WAS RETURNED BACK INTO SERVICE ON AUGUST 25, 2016 AT 09:20 AM. SUBSEQUENTLY, THE PLC PROGRAM AND ESD SYSTEMS HAVE BEEN REVIEWED AND MODIFIED TO PREVENT RE-OCCURRENCE. THE ROOT CAUSE ANALYSIS INVESTIGATION NOTED CERTAIN KEY COMPONENTS THAT WERE IDENTIFIED AS CONTRIBUTING FACTORS THAT MAY HAVE LED TO THE UNINTENDED ESD OF THE SMITHFIELD CS. THEY WERE: (I) ALARMS AND SYSTEM FAULTS WERE TO BE INVESTIGATED PRIOR TO ACKNOWLEDGEMENT AND CLEARING. NOTIFICATION PROCESS AND PROCEDURES MUST BE FOLLOWED. (II) ESD PILOT AIR SYSTEM TO BE TESTED AND INSPECTED TO ENSURE THAT IT FUNCTION AS REQUIRED. (III) AFTER AN ESD SYSTEM MALFUNCTION, THE ESD SYSTEM DESIGN MAY NEED TO BE RE-EVALUATED TO ENSURE THAT IT PERFORMS AS REQUIRED AND EXPECTED. (IV) ALARMS THAT DISABLE ESSENTIAL STATION COMPONENTS NEED TO BE FULLY VETTED AND INVESTIGATED TO IDENTIFY THE SOURCE AND TO REMEDY THE ISSUE. THE LISTED FOUR ITEMS IN THE RCA REPORT WERE IMPLEMENTED AND COMPLETED WHERE THE FACILITY DID NOT EXPERIENCE ANY SIMILAR INDICATIONS THAT MAY POTENTIALLY INITIATE AN ESD SYSTEM FAILURE, SUBJECT TO THE CORRECTED KEY ITEMS IN THE RCA REPORT.