PLAINS PIPELINE, L.P.

Incident Narrative

APPROXIMATELY 360 BBLS OF CRUDE OIL WERE RELEASED WHEN THE VALVE ACTUATOR SEPARATED FROM A MOTOR-OPERATED VALVE. OIL SPRAYED BEYOND STATION BOUNDARIES ONTO AN ADJACENT BUSINESS TO THE NORTH. THE OIL WAS CONTAINED AND RECOVERY COMPLETED. ASSESSMENT OF SUBSURFACE IMPACT IS ONGOING. THE VALVE HAS BEEN SENT TO THE LAB TO UNDERGO METALLURGICAL ANALYSIS AND A SUPPLEMENTAL REPORT WILL BE SUBMITTED ONCE THE LAB RESULTS ARE RECEIVED. THE NATIONAL RESPONSE CENTER (NRC) WAS NOTIFIED AND ASSIGNED REPORT NUMBER 1082838. SUPPLEMENTAL NARRATIVE: BASED ON THE RESULTS OF THE METALLURGICAL ANALYSIS, IT HAS BEEN DETERMINED THAT THE SUBJECT LEAK WAS THE RESULT OF TENSILE FATIGUE OF THE CAP SCREWS THAT ATTACHED THE VALVE STEM GLAND TO THE VALVE BODY. WHILE ENGINEERING CALCULATIONS DETERMINED THE CAP SCREWS WERE SUFFICIENT TO SUPPORT THE LOADS ON THE VALVE ARISING FROM INTERNAL PRESSURE AND ACTUATOR TORQUE WHEN STATIC, THE METALLURGICAL ANALYSIS ALSO SUPPORTS THE LIKELIHOOD THAT VIBRATION SIGNIFICANTLY CONTRIBUTED TO THE FATIGUE FAILURE OF THE CAP SCREWS. PLAINS HAS REPLACED THE VALVE WITH A WKM 14-INCH POWER SEAL GATE VALVE. AFTER THE REPLACEMENT OF THE BALL VALVE WITH A GATE VALVE, A SUBSEQUENT VIBRATION STUDY CONCLUDED THAT THE VIBRATIONS AT ALL MEASURED LOCATIONS AND DIRECTIONS TO BE BELOW THE LEVEL OF CONCERN AS DEFINED BY THE ENERGY INSTITUTE (EI). THE SOIL ASSESSMENT FOR BOTH ONSITE AND OFFSITE CONCLUDED THE AREAS MEET PUBLISHED CLEAN-UP GOALS.