TENNESSEE GAS PIPELINE COMPANY

Incident Narrative

ON AUGUST 18, 2023, AT 08:00, AN EXPLOSION AND FIRE OCCURRED AT THE CENTERVILLE COMPRESSOR STATION 860 IN THE ""A"" COMPRESSOR BUILDING WHICH LED TO MAJOR EQUIPMENT DAMAGE WITHIN THE COMPRESSOR BUILDING. THERE WAS A GAS RELEASE AND IGNITION ON UNIT 10A AT TGP 860. UNIT 10A IS A CLARK TLA-8, WITH (4) ENBLOC COMPRESSORS. THE #2 COMPRESSOR HEAD END UNLOADER (HEU) FLANGE CRACKED IN THE FILLET AND RELEASED THE GAS THAT IGNITED CAUSING A SUBSEQUENT FIRE. AT 08:16, AN OPERATIONS EMPLOYEE PULLED THE MANUAL ESD HANDLE TO ACTIVATE THE STATION ESD SYSTEM. ANOTHER EMPLOYEE CALLED 911. ALL EMPLOYEES AND CONTRACTORS WORKING AT THE STATION SAFELY EVACUATED THE FACILITY AND MET AT THE EVACUATION POINT LOCATED AT THE STATION SECURITY GATE TO CONFIRM ALL PERSONNEL WERE ACCOUNTED FOR. IN AN ABUNDANCE OF CAUTION LOCAL EMERGENCY RESPONDERS EVACUATED THE SURROUNDING AREA FOR A FEW HOURS. THERE WERE NO OFF SITE IMPACTS. THERE WERE NO INJURIES OR FATALITIES. ONE EMPLOYEE WAS TRANSPORTED TO THE HOSPITAL WITH SYMPTOMS THAT WERE NOT DIRECTLY RELATED TO THE INCIDENT. THE INVESTIGATION TEAM DETERMINED THAT THE #2 HEU ASSEMBLY HAD AN INHERENT DESIGN FLAW FROM THE ORIGINAL EQUIPMENT MANUFACTURER (OEM), WITH A CONTRIBUTING FACTOR OF OVER TORQUEING THE HEU FLANGE DURING REASSEMBLY ON MONDAY, AUGUST 14, 2023 BY THE LOCAL MECHANICAL CREW. THE INCIDENT INVESTIGATION REPORT HAS BEEN PROVIDED TO PHMSA.