SHELL PIPELINE CO., L.P.

Incident Narrative

DURING A SET POINT INCREASE OF THREE POUNDS OF DISCHARGE PRESSURE AT AN INTERMEDIATE PUMP STATION BY THE CONTROLLER, THE PIPE SECTION APPROX. 0.5 MILES DOWNSTREAM RUPTURED. THE CONTROLLER IMMEDIATELY IDENTIFIED THE RELEASE BY THE PUMP STATION INCREASED FLOW RATE AND LOW SUCTION SHUTDOWN OF THE PUMP STATION. THE CONTROLLER TOOK IMMEDIATE ACTION TO SHUTDOWN THE ENTIRE PIPELINE AND CLOSING INTERMEDIATE BLOCK VALVES. THE CONTROLLER THEN CLOSED OFF THE RECEIVING LOCATION TO REDUCE THE RELEASE OF CRUDE OIL. THE CONTROLLERS ACTIONS FROM THE TIME OF THE LOW SUCTION SHUTDOWN OF THE PUMP STATION UNIT TO THE SHUTDOWN OF THE PIPELINE SYSTEM WAS TWO MINUTES. THIS IS FASTER THAN THE CPM SYSTEM CAN IDENTIFY A RELEASE. THE CONTROLLER THEN CONTACTED THE LOCAL & ON CALL SUPERVISORS, THE CONTROLLER CONSOLE SUPERVISOR TO INFORM THEM OF HIS ACTIONS. THE LOCAL SUPERVISOR CALLED OUT TWO PERSONNEL TO BEGIN LOOKING FOR THE RELEASE SITE. TIMING WAS AFTER DARK WITH LIMITED VISIBILITY. THE PERSONNEL DROVE THE AREA NORTH OF THE PUMP STATION. THE TOPOGRAPHY IS ROLLING HILLS AND PASTURE LAND WITH LIMITED ACCESS. THEY DID NOT SEE THE RELEASE SITE WHERE THEY WERE ABLE TO DRIVE. THE AIR PATROL WAS CALLED TO BE OVER THE PUMP STATION AND HEAD NORTH AT FIRST LIGHT. THE AIR PATROL IDENTIFIED THE LOCATION AT 07:05 HRS. METALLURGICAL EXAMINATION REPORT - ""THE PIPE SECTION RUPTURED AT A PREEXISTING FATIGUE CRACK. THE FATIGUE CRACK INITIATED FROM SMALL CORROSION PITS ALONG THE INTERNAL SURFACE AT THE TOE OF THE LONGITUDINAL SEAM WELD. EVIDENCE OF INTERLINKED INCLUSIONS WERE OBSERVED, ALONG WITH A STEPWISE FRACTURE MORPHOLOGY, SUGGESTING THAT STRESS-ORIENTED HYDROGEN INDUCTED CRACKING (SOHIC) MAY HAVE CONTRIBUTED TO THE FAILURE."" 10/24/16 UPDATED MANUFACTURER ARMCO 1982 & SUB-CAUSE ORIGINAL MANUFACTURING-RELATED.