TENNESSEE GAS PIPELINE COMPANY

Incident Narrative

"ON DECEMBER 29, 2024, BATESVILLE COMPRESSOR STATION 63 ON THE TENNESSEE GAS PIPELINE (TGP) SYSTEM EXPERIENCED AN ESD EVENT. GAS CONTROL IMMEDIATELY CONTACTED TGP OPERATIONS AT 01:45 CST. THE OPERATIONS TEAM ARRIVED ON SITE AT 2:05 CST AND CONFIRMED THAT GAS WAS VENTING. THE KM TECHNICIAN IDENTIFIED VALVE 63-1S TO BE UNEXPECTEDLY OPEN AND CLOSED THE VALVE AND SECURED THE GAS RELEASE. THE NRC WAS CALLED AT 3:04 CST BY KM PERSONNEL AND THE INITIAL REPORT WAS CAPTURED AS RECEIVED BY 3:07 CST. A 48-HOUR NRC REPORT WAS MADE TO UPDATE THE GAS RELEASE VOLUME TO 49,399 MCF. INITIAL INVESTIGATION DETERMINED THAT LIGHTNING HAD STRUCK THE BUILDING PROTECTION SYSTEM IN COMPRESSOR BUILDING ""B"" CAUSING A LOSS OF COMMUNICATION WITH THE STATION CONTROLS. THIS LOSS OF COMMUNICATION ACTIVATED THE TGP ESD FAIL SAFE SYSTEM. FOLLOWING AN INVESTIGATION REGARDING THE VALVE OPERATION, IT WAS DETERMINED THAT THE ROOT CAUSE OF THE ISSUE WAS THE FAILURE OF AN OBSOLETE ACTUATOR WHICH RESULTED IN THE VALVE ACTUATING TO THE OPEN POSITION RATHER THAN THE INTENDED CLOSED POSITION. THE FAILURE MAY HAVE BEEN ATTRIBUTED TO INTERNAL DEBRIS OR WORN COMPONENTS WITHIN THE ACTUATOR. UPON FURTHER REVIEW OF THE ESD SYSTEM, IT WAS CONCLUDED THAT SIX VALVES, INCLUDING VALVE 63-1S, WERE EQUIPPED WITH ESD ACTIVATION THAT WAS NOT FUNCTIONALLY REQUIRED. AS A RESULT, AN INITIATIVE WAS IMPLEMENTED TO RECONFIGURE THESE VALVES WITHIN THE SYSTEM TO REDUCE THE LIKELIHOOD OF MECHANICAL FAILURES."