COLONIAL PIPELINE CO

Incident Narrative

DUE TO CHARACTER LIMITATIONS, CONTENTS OF THE NARRATIVE PROVIDED WITHIN SUPPLEMENTAL REPORT FILED 2/5/2017 HAVE BEEN DELETED, BUT ARE INCORPORATED HERE AS IF RESTATED IN FULL. NARRATIVE UPDATE 8/11/2017 THE NATIONAL TRANSPORTATION SAFETY BOARD (NTSB) RELEASED A PIPELINE ACCIDENT BRIEF (PAB) ON 6/15/2017 WHICH PRESENTED THE RESULTS OF ITS INVESTIGATION OF THE CENTREVILLE INCIDENT (PAB-17/01, ADOPTED BY NTSB ON 6/5/2017). AS PROVIDED IN THE PAB, NTSB DETERMINED THAT THE PROBABLE CAUSE OF THE RELEASE WAS A ""THROUGHWALL CORROSION FATIGUE THAT DEVELOPED AT A DENT IN THE PIPELINE DUE TO RESIDUAL AND OPERATIONAL STRESS & EXPOSURE TO THE UNDERGROUND ENVIRONMENT"". COLONIAL CONCURS THAT THE CRACK DEVELOPED DUE TO FATIGUE CAUSED BY MULTIPLE FACTORS INCLUDING PRESSURE CYCLING, BUT COLONIAL DOES NOT BELIEVE THAT THE PRESENCE OF CORROSION AT THE FAILURE SITE HAD ANY IMPACT ON THE LEAK OCCURRENCE. CORROSION AT THE LEAK LOCATION WAS TOO LIMITED TO HAVE ANY APPRECIABLE IMPACT ON THE DEVELOPMENT AND FULL THROUGH-WALL PROPAGATION OF A CRACK. PHMSA'S ACCIDENT INVESTIGATION DIVISION DIRECTED COLONIAL TO INCLUDE THE SPECIFIC DATES/TIMES AS SET FORTH IN THIS FORM'S PART A #4, #18A, AND #18B. NOTWITHSTANDING THAT, HOWEVER, COLONIAL MAINTAINS: (1) AS TO #4 - THE APPROPRIATE DATE/TIME OF THE ACCIDENT (I.E., WHEN 'ACCIDENT REPORTING CRITERIA WAS MET') IS ""9/21/2015 20:53"", WHEN COLONIAL RECEIVED THE CALL FROM THE FAIRFAX COUNTY FIRE MARSHAL REPORTING A SHEEN ON THE RETENTION POND. (2) AS TO #18A - THE APPROPRIATE DATE/TIME WHEN COLONIAL 'IDENTIFIED THE ACCIDENT' IS ""9/23/2015 09:57"", WHEN COLONIAL CONFIRMED THAT THE RELEASE ORIGINATED FROM ITS PIPELINE. PRIOR TO THAT TIME, COLONIAL HAD NOT 'IDENTIFIED THE FAILURE' - COLONIAL'S PIPELINES WERE LOCATED SOME DISTANCE AWAY FROM THE POND AND THERE WERE MULTIPLE OTHER POTENTIAL SOURCES OF THE ODORS AND/OR SHEEN. IN RESPONSE TO THE REPORT OF A SHEEN, COLONIAL INITIATED THE SHUTDOWN OF ITS PIPELINE AS A PRECAUTIONARY MEASURE, EVEN THOUGH THE SOURCE HAD NOT BEEN IDENTIFIED. COLONIAL REPORTED GASOLINE 'FROM AN UNKNOWN SOURCE' TO THE NRC ON 9/22/2015 AT 01:32. COLONIAL 'IDENTIFIED THE FAILURE' ON 9/23/2015 AT 09:57 WHEN PRODUCT WAS OBSERVED LEAKING FROM COLONIAL'S LINE 4 PIPELINE. UNTIL THAT TIME, THERE WAS NO DEFINITIVE CONNECTION BETWEEN THE SHEEN ON THE RETENTION POND AND COLONIAL'S PIPELINE, WHICH WAS SOME DISTANCE AWAY FROM THE POND. (3) AS TO #18B - THE APPROPRIATE DATE/TIME WHEN COLONIAL 'RESOURCES ARRIVED ON SITE' IS ""9/23/2015 09:57"". COLONIAL RESOURCES ARRIVED ON THE SCENE PRIOR TO THAT DATE/TIME, BUT THIS FORM'S INSTRUCTIONS PROVIDE THAT #18B MUST BE CONCURRENT WITH OR LATER THAN #18A (WHEN THE ACCIDENT WAS IDENTIFIED BY COLONIAL). UPDATE APRIL 2020: DURING THE TIME PERIOD THAT THIS RELEASE OCCURRED, COLONIAL HAD EXPERIENCED SEVERAL OTHER RELEASES THAT HAD THE SAME FAILURE MODE. THE IA THAT FOLLOWED THIS INCIDENT WAS CONSOLIDATED WITH THE OTHER RECENT FATIGUE CRACK IN DENT FAILURES, AND WAS ADDRESSED AS ONE COMPREHENSIVE, SYSTEM-WIDE ASSESSMENT OF THE FACTORS CONTRIBUTING TO THE DEVELOPMENT OF FATIGUE CRACKS IN DENTS. THIS APPROACH WAS TAKEN BY COLONIAL TO ENSURE THAT THE LESSONS LEARNED FROM ALL OF THE INCIDENTS COULD BE FACTORED INTO THE CORRECTIVE ACTION PLAN AND DRIVE IMPROVEMENTS SYSTEM-WIDE. THE IA INCLUDED METALLURGICAL ANALYSES OF THREE OF THE DENT FAILURES, ALL CONFIRMING THAT PRESSURE CYCLING OF THE DENT RESULTED IN THROUGH WALL FATIGUE CRACKS. THE PRESENCE OF THE DENT CONCENTRATED STRESSES ON THE PIPELINE, CREATING A FATIGUE CRACK TO FORM AND GROW THROUGH-WALL OVER TIME DUE TO PRESSURE CYCLING.