EXPLORER PIPELINE CO

Incident Narrative

ON OCTOBER 2, 2016 EXPLORER PIPELINE'S CONTROL CENTER RECEIVED A VAPOR ALARM AT THE MOUNT VERNON, MISSOURI PUMP STATION. THE VAPOR MONITOR ALARM WAS INTERMITTENT, AND WOULD RETURN TO NORMAL STATE. CONTROL CENTER PERSONNEL RESPONDED TO THE ALARM RETURNING TO NORMAL. THE ALARM WAS INTERMITTENT, ALARM/NORMAL FIRST OCCURRED AT 10:38. CONTROL CENTER MONITORED VIDEO SURVEILLANCE OF THE PUMP STATION GROUNDS, AND NO VISIBLE EVIDENCE OF A RELEASE WAS IDENTIFIED. LOCAL EXPLORER PERSONNEL WERE DISPATCHED TO REVIEW A POTENTIAL MALFUNCTION OF A VAPOR ALARM, AND INSPECT THE STATION. AFTER ARRIVAL, LOCAL PERSONNEL IDENTIFIED LEAK INSIDE A STATION VAULT. LOCAL EXPLORER PERSONNEL IDENTIFIED THE RELEASE HAD ORIGINATED FROM A PLUG ASSOCIATED WITH THE STATION UNIT 1 DISCHARGE VALVE THAT IS TOTALLY CONTAINED IN AN UNDERGROUND VALVE VAULT. ALL THE PRODUCT THAT WAS RELEASED FROM THE PLUG WAS TOTALLY CONTAINED INSIDE THE VAULT AND TOTALLY CONTAINED INSIDE THE STATION. THE DIRECT SOURCE OF THE RELEASE WAS A GROVE G4 GATE VALVE PLUG ON THE BOTTOM SIDE OF THE BELOW GROUND VALVE INSIDE THE VAULT. THE PLUG WAS FROM ORIGINAL 1971 CONSTRUCTION, AND ALL INDICATIONS ARE THE PLUG WAS NOT PROPERLY THREADED ALL THEY WAY INTO THE VALVE. THE COSTS FOR THE RESPONSE AND ANY CLEAN-UP FOR THE RELEASE THAT WAS TOTALLY CONTAINED IN THE VAULT AND ON THE PROPERTY WAS CALCULATED TO BE BELOW THE $50,000 FOR 49 CFR 195.52(A)(3). HOWEVER, THE FINAL ACTUAL COSTS EXCEEDED THE $50,000 COST ESTIMATE BY $15,000.