WESTERN REFINING PIPELINE, LLC

Incident Narrative

AT 12:03 ON 9/15/16, WESTERN REFINING PIPELINE, LLC CONTROL CENTER RECEIVED A SUMP TANK HIGH ALARM AT ITS PECAN STATION. THE CONTROL ROOM INITIATED A STATION SHUT DOWN. FIELD PERSONNEL WERE NOTIFIED, AND UPON ARRIVING AT THE STATION DISCOVERED CRUDE OIL OVERFLOWING THE STATION SUMP TANK. PERSONNEL THEN ISOLATED THE STATION AND CONTROLLED THE SPILL. PRELIMINARY INDICATIONS OF THE INCIDENT POINT TOWARDS THE FAILURE OF A THERMAL RELIEF VALVE CAUSING THE OVERFILL. WESTERN IS SENDING THE THERMAL RELIEF VALVE TO A THIRD PARTY FOR ANALYSIS TO UNDERSTAND THE CAUSE OF FAILURE, AND TO PREVENT ANY FUTURE SIMILAR OCCURRENCES. UPON RECEIVING THE RESULTS, ADDITIONAL INFORMATION WILL BE PROVIDED WITHIN THE SUPPLEMENTAL REPORT PERTAINING TO THIS EVENT. THE CONTROL ROOM CONTROLLERS WERE CLEARED OF CAUSING OR CONTRIBUTING TO THIS EVENT. CORRECTED TRV THAT FAILED OPEN. CORRECTED MALFUNCTIONING LEVEL TRANSMITTER NOT FUNCTIONING PROPERLY DURING THIS EVENT. A THOROUGH EVALUATION OF THE FAILED TRV DID NOT REVEAL A DEFINITIVE CAUSE FOR THE LEAK AT ITS OUTLET. INTERIOR COMPONENTS OF THE FAILED TRV DID NOT EXHIBIT SIGNS OF WEAR OR DAMAGE. DEBRIS OF UNKNOWN ORIGIN WAS FOUND AT THE DISC AND DISC HOLDER THAT SERVES AS A SEAT. NO DEBRIS WAS FOUND ON THE DISC AND DISC HOLDER COMPONENTS OF THE CONTROL OR INTACT TRV FROM A NEARBY LOCATION, FOR THE BENEFIT TO THE STUDY. THE TRV DID NOT HAVE ANY SIGNS OF WEAR OR DAMAGE THAT WOULD LEAD US TO BELIEVE THERE IS A SYSTEMIC PROBLEM WITH THESE TRVS IN OUR SYSTEM. THIRD PARTY EXAMINATION OF THE TRV REVEALED INDICATIONS OF DEBRIS IN THE VALVE LEADING US TO BELIEVE THERE WAS SOME TYPE OF DEBRIS THAT BECAME LODGED IN THE TRV WHICH CAUSED THE TRV TO STICK OPEN ALLOWING CRUDE TO FLOW INTO THE SUMP TANK. CRUDE OIL ENTERING OUR PIPELINE SYSTEM GOES THROUGH STRAINERS. IT IS THOUGHT THE DEBRIS CAUSING THE TRV TO STICK OPEN WAS FROM THE RECENTLY COMMISSIONED METER STATION. THE INDEPENDENT SUMP HIGH LEVEL ALARM WORKED AS IT WAS INTENDED BY INITIATING A PIPELINE SHUTDOWN SEQUENCE AND ALERTING THE CONTROL CENTER OF THE HIGH LEVEL CONDITION. UPON RECEIVING THE ALARM, CONTROL CENTER OPERATOR ALSO EXECUTED PIPELINE SHUTDOWN COMMANDS. A SUMP LEVEL TRANSMITTER, WHICH WAS MALFUNCTIONING DURING THE EVENT, CONTROLLED THE AUTOMATIC START/STOP OF THE SUMP PUMP. THE TRANSMITTER PREVENTED THE SUMP PUMP FROM OPERATING, WHICH ALLOWED THE SUMP TO OVERFILL SOONER. THE SETTINGS ON THE MALFUNCTIONING LEVEL TRANSMITTER WERE ADJUSTED AND CORRECTED AFTER THE INCIDENT AND BEFORE THE SUMP WAS RETURNED TO SERVICE.