COLUMBIA GAS TRANSMISSION, LLC

Incident Narrative

ON SEPTEMBER 16, 2015, A COLUMBIA GAS TRANSMISSION, LLC (COLUMBIA) TRANSMISSION PIPELINE WAS SUBJECT TO UNINTENDED RELEASE OF NATURAL GAS (MATERIAL) INTO ATMOSPHERE DUE TO A DAMAGE TO AN OLD TAP BY COLUMBIA PERSONNEL. THE SITE WAS UNDERWORK IN PREPARATIONS FOR A NEW TAP. THE MATERIAL DID NOT IGNITE AND THE COLUMBIA PERSONNEL NOTIFIED THE LOCAL EMERGENCY RESPONDERS (TO SECURE THE AREA) AND THE MONITORING CENTER. EMERGENCY VALVES WERE OPERATED TO ISOLATE THE AFFECTED SEGMENT. AFTER ISOLATING THE AFFECTED SEGMENT, NECESSARY REPAIR STEPS WERE IMPLEMENTED WHERE A PRE-TESTED PIPE WAS INSTALLED. THE PIPELINE WAS REPAIRED, PURGED AND RETURNED TO SERVICE AFTER APPROXIMATELY FOUR HOURS OF DISRUPTED SERVICE AND THE LOCAL DISTRIBUTION COMPANY (LDC) RE-ESTABLISHED SERVICE TO THEIR CUSTOMERS. AN INVESTIGATION WAS INITIATED TO IDENTIFY THE CAUSAL FACTORS LEADING TO THE DAMAGE OF THE OLD TAP AND HOW IT CAN BE PREVENTED FROM RE-OCCURRING IN SIMILAR FUTURE APPLICATIONS. EVEN THOUGH THE TOTAL AMOUNT OF MATERIAL UNINTENTIONALLY RELEASED INTO ATMOSPHERE AND COST OF DAMAGES DID NOT EXCEED THE REPORTING THRESHOLD, COLUMBIA REPORTED THIS EVENT AS AN INCIDENT DUE TO THE NUMBER OF LDC CUSTOMERS AFFECTED BY THIS DISRUPTION OF SERVICE. SUPPLEMENTAL INFORMATION: ON 10/19/2015 AS A FOLLOW-UP TO THE INCIDENT, AN INTERNAL COLUMBIA PIPELINE GROUP ""SAFETY ALERT"" WAS RELEASE TO CPG EMPLOYEES DESCRIBING THE EVENT AND WARNING EMPLOYEES TO USE CAUTION WHEN MECHANICALLY EXCAVATING, PARTICULARLY AROUND STOPPLE FITTINGS AND TO SUSPECT, AND WATCH FOR SIDE CONNECT BYPASSES.