MONROE GAS STORAGE COMPANY, LLC

Incident Narrative

ON FRIDAY AFTERNOON 9/20/24 AT 13:21 CT, A TECHNICIAN AT THE MONROE GAS STORAGE COMPRESSOR STATION OBSERVED SMALL BUBBLES RISING WITHIN A PUDDLE OF WATER WHILE DOING REGULAR INSPECTION ROUNDS WITHIN THE FENCED FACILITY. AFTER CONFIRMING THE PRESENCE OF NATURAL GAS AT THE LOCATION AND SUSPECTING A PINHOLE LEAK, THE 18"" EASTSIDE GAS TRANSMISSION LINE WAS ISOLATED BY MANUALLY CLOSING THE DOWNSTREAM VALVES. BECAUSE THE LINE WAS NOT FLOWING AT THE TIME, THE UPSTREAM VALVES WERE ALREADY CLOSED. THE EFFECTED LINE SEGMENT WAS ISOLATED BY 14:13 CT. AFTER INITIAL COORDINATION REGARDING POSSIBLE COST OF REPAIR, IT WAS DETERMINED TO CLASSIFY THE EVENT AS AN INCIDENT AND NOTIFY THE NATIONAL RESPONSE CENTER (NRC). THE NRC WAS NOTIFIED BY THE WILLIAMS SECURITY OPERATIONS CENTER AT 15:27 CT. THE PIPELINE WAS SAFELY BLOWN DOWN WITH LOCK OUT / TAG OUT COMPLETED BY 19:20 CT THAT EVENING. DUE TO THE PIPELINE'S 10' DEPTH IN THE AREA, IT TOOK MULTIPLE DAYS FOR CONTRACTORS TO CLEAN THE LINE THROUGH CLEANING PIGS, PURGE WITH NITROGEN AND POTHOLE THROUGH HYDROVACING TO PINPOINT THE LEAK LOCATION. ONCE IDENTIFIED (THROUGH DETECTING THE PRESENCE OF NITROGEN), THE LEAK LOCATION WAS FULLY AND SAFELY EXCAVATED (CONSIDERING THE SIGNIFICANT DEPTH) ON 10/14/24. AS OF 10/15/24, INTERNAL CORROSION WAS FOUND AT THE PINHOLE LEAK LOCATION. THE EFFECTED PIPE IMMEDIATELY NEAR THE LEAK LOCATION IS SCHEDULED TO BE CUT-OUT ON 10/17/24 AND SENT TO A LAB FOR ANALYSIS. THE REMAINING PIPE WILL BE VISUALLY INSPECTED IN BOTH DIRECTIONS TO FURTHER ASSESS THE EXTENT OF INTERNAL CORROSION. AFTER THE INITIAL SUBMITTAL OF THIS 30-DAY INCIDENT REPORT, A SUPPLEMENTAL REPORT WILL BE FILED NOTING MORE INFORMATION ON THE VERIFIED CAUSE AND MITIGATIVE ACTIONS TAKEN.