SUNOCO PIPELINE L.P.

Incident Narrative

DURING A ROUTINE FACILITY INSPECTION AT APPROXIMATELY 14:30 ON 9/14/2017 OPERATIONS PERSONNEL DISCOVERED AN OVERFLOW OF APPROXIMATELY ONE BARREL OF CRUDE FROM THE SUMP AT THE INJECTION STATION OF THE EAST ANDREWS GATHERING SYSTEM. INVESTIGATION DETERMINED THAT A 1/2"" THERMAL RELIEF VALVE PLUMBED TO THE SUMP FAILED OPEN AND DID NOT RE-SEAT FOLLOWING ACTUATION WHICH RESULTED IN THE OVERFILL. THE GATHERING INJECTION DOES NOT RUN CONTINUOUSLY AND WAS NOT RUNNING AT THE TIME OF THE RELEASE. THE 1/2"" RELIEF VALVE IS UTILIZED TO RELIEVE THERMAL PRESSURE BETWEEN A CHECK VALVE JUST DOWNSTREAM OF THE INJECTION PUMP AND AN MOV WHICH IS OPENED ONLY WHEN THE INJECTION IS BEING STARTED AND RUNNING. THE SUMP THE THERMAL RELIEF VALVE IS PLUMBED TO IS MANUALLY ACTIVATED. THE CONTROL CENTER DOES NOT SEE THE THERMAL RELIEF VALVE OR THE SUMP VIA SCADA. THE NEAREST PRESSURE TRANSMITTER THAT IS MONITORED VIA SCADA IS LOCATED UPSTREAM OF THE INJECTION PUMP AND INDICATED APPROXIMATELY 70 PSI AT THE ESTIMATED TIME OF 5 GALLONS BEING RELEASED FROM THE SUMP. ALL CONTAMINATED SOIL WAS REMOVED FROM THE SITE BY COMPANY PERSONNEL. THE FAILED 1/2"" THERMAL RELIEF VALVE WAS REPLACED AND THE INJECTION WAS RETURNED TO NORMAL SERVICE.