SOUTHERN STAR CENTRAL GAS PIPELINE, INC

Incident Narrative

ON 3/25/2019 AT 3:13 AM LOCAL TIME, SOUTHERN STAR CENTRAL GAS PIPELINE (SSCGP) GAS CONTROL RECEIVED AN ALARM THAT AN AUTOMATIC EMERGENCY SHUTDOWN (ESD) WAS UNDERWAY AT THE HESSTON COMPRESSOR STATION IN HARVEY COUNTY, KANSAS. OPERATIONS PERSONNEL WERE DISPATCHED TO THE STATION ARRIVING AT 3:46 AM. UPON ARRIVAL IT WAS NOTICED THAT GAS WAS STILL VENTING OUT OF THE STATION BLOW-OFF STACK. IT WAS DETERMINED THAT VALVE #42 FAILED TO CLOSE AUTOMATICALLY AND IT WAS CLOSED MANUALLY USING GAS POWER AT 3:56 AM AND THE GAS RELEASE STOPPED. SINCE THE GAS RELEASE WAS PART OF AN ESD IT WAS NOT IMMEDIATELY DETERMINED THAT THIS WAS A REPORTABLE EVENT. A SOLENOID VALVE IN THE BASEMENT FOR THE ESD SYSTEM WAS REPLACED AND THE STATION WAS BROUGHT BACK INTO OPERATION AT 7:15 AM. THE INITIAL GAS LOSS ESTIMATE WAS MADE AT 7:30 AM AND IT WAS DETERMINED THAT THIS WOULD BE A REPORTABLE EVENT AND THE NRC WAS CALLED AT 7:46 AM (NRC#1240963). AFTER INVESTIGATING THE ISOLATION VALVE, THE CAUSE OF THE FAILURE OF THE VALVE TO CLOSE WAS BECAUSE SOME MATERIAL HAD BUILT UP IN THE OPERATOR OF THE VALVE. ALL COMPONENTS OF THE VALVE WERE CLEANED OUT. ALL OF THE ESD LINES WERE ISOLATED AND BLOWN OUT TO REMOVE ANY DEBRIS THAT MAY HAVE BEEN REMAINING IN THE LINE.