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PHMSA Releases Preliminary Results for Plains Pipeline Failure Investigation

Wednesday, February 17, 2016

WASHINGTON – The U.S. Department of Transportation’s Pipeline and Hazardous Materials Safety Administration (PHMSA) today provided a preliminary report regarding its investigation into the Plains All American pipeline failure, which occurred on May 19, 2015, in Santa Barbara County, California.  The report contains preliminary factual information regarding the events leading up to the pipeline failure, including a timeline of events and the results of technical analyses that have been conducted to date.  PHMSA is still investigating the incident, and a final investigation report will be released later this year. 

“This pipeline failure had devastating impacts, spilling more than 120,000 gallons of crude oil along a pristine stretch of Gaviota Beach in California and into the Pacific Ocean.  The spill has had profound effects on people and the environment – from an ecological perspective, to impacts on wildlife, recreation and the local economy,” said U.S. Transportation Secretary Anthony Foxx. “The preliminary report is an important step forward that will help us learn what went wrong, so that everyone involved can take action and ensure that it doesn’t happen again.”

The report includes details obtained from the required metallurgical analysis conducted on the failed section of the pipeline following the incident, and a third-party review of in-line inspection   results for Lines 901 and 903.  Plains conducted ILI surveys on Line 901 to assess the integrity of the pipeline in 2007, 2012, and 2015.  According to the metallurgical report, the failure occurred at an area on the pipe weakened by the existence of external corrosion under the pipe insulation.  PHMSA’s final accident investigation report will incorporate all aspects of the events leading up to the release and all contributory causes, including details as to the specific cause of the external corrosion and information about the operator’s adherence to federal regulations regarding the operation of Lines 901 and 903.

“As PHMSA works to complete our investigation of this incident, we are examining the technical cause of the failure, as well as any contributing factors which may have impacted the severity of this incident as well as the safety of people and the environment,” said PHMSA Administrator Marie Therese Dominguez.

Since the failure, PHMSA has required Plains to take a number of actions to restore and rehabilitate the safety and integrity of their pipelines.  PHMSA’s review of the Plains’ internal inspection results, which the operator conducted before the failure, discovered instances where the inspection tool miscalculated the degree of corrosion occurring in specific portions of Line 901 and Line 903.  As a result, PHMSA ordered Plains to remove all crude oil from Line 903 to reduce the risk of corrosion and any impact the pipeline’s safety and integrity.  Additional details regarding the directive can be found in PHMSA’s Amendment to the Corrective Action Order.

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Federal investigation identifies corrosion as key factor in cause of crude oil release from pipeline along California coast