SUNOCO PIPELINE L.P.

Incident Narrative

ON 2/08/21 AT APPROXIMATELY 18:38 CST, UPON LINING UP VALVES FOR A DELIVERY INTO A 3RD PARTY TERMINAL FACILITY THE PIPELINE CONTROLLER RECEIVED AN LEL ALARM PRIOR TO INITIATING THE DELIVERY. AT THE TIME THE DELIVERY PIPING WAS IN A STATIC CONDITION AND UPON RECEIVING THE ALARM THE CONTROLLER ABORTED THE DELIVERY. NOTIFICATIONS TO SUPERVISOR AND FIELD PERSONNEL WERE MADE. AT 20:45 EST FIELD PERSONNEL CONFIRMED A LEAK ORIGINATING AT A FILTER VESSEL CLOSURE (O-RING). THE FILTER WAS ISOLATED, DE-INVENTORIED AND THE O-RING WAS REMOVED AND REPLACED. CAUSE OF THE O-RING FAILURE IS UNDER INVESTIGATION BY THE O-RING MANUFACTURER. THE FILTER VESSEL EQUIPMENT IS CURRENTLY BYPASSED UNTIL THE CAUSE OF THE O-RING FAILURE IS DETERMINED. SCHEDULED DELIVERIES TO THE 3RD PARTY CONTINUE TO OCCUR ON SCHEDULE. 4/15/21 THE EQUIPMENT MANUFACTURER DETERMINED THE O-RING FAILED DUE TO THERMAL (REFRIGERATION) EFFECTS ON THE O-RING ASSOCIATED WITH RAPID DECOMPRESSION RELATED TO NORMAL PRESSURE CYCLING ASSOCIATED WITH THE DELIVERY. MANUFACTURER SUGGESTED AN O-RING WITH A GREATER COLD TEMPERATURE RATING MAY RESOLVE THE LEAK PROBLEM. ET ENGINEERING AND OPERATIONS DETERMINED THAT THE SUGGESTED O-RING WILL BE USED AND WILL ALSO IMPLEMENT A SHUTDOWN VALVE SEQUENCE CHANGE TO LIMIT THE RANGE OF PRESSURE CYCLING ON SHUT DOWN.