WEDNESDAY, DECEMBER 6, 2017
TransCanada’s Keystone Pipeline resumed operation in a limited capacity last week in the wake of a Nov. 16 spill in Amherst, South Dakota, that may have been caused by damage inflicted on the pipe itself or on its protective coating during construction.
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| shannonpatrick17, CC BY 2.0, via Wikimedia Commons |
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Investigators say last month's release on the Keystone Pipeline in South Dakota may have been caused by mechanical damage to the pipe or its coating that occurred during construction nearly 10 years ago. |
The Pipeline and Hazardous Materials Administration, a division of the U.S. Department of Transporation, said in a preliminary report Nov. 28 that the rupture “may have been caused by mechanical damage to the pipeline and coating associated with a weight installed on the pipeline in 2008,” during the line’s original construction. The weight would have been placed there due to concerns about buoyancy potentially caused by groundwater.
The spill reportedly resulted in the release of 5,000 barrels of crude oil.
Pipe Details
The portion of the pipe affected was removed and sent to a National Transportation Safety Board lab for metallurgical testing, and the pipe was repaired and placed back into service at 80 percent capacity on Nov. 28.
The section of pipe that failed, the PHMSA says in its report, is a 30-inch steel pipe with a double-submerged arc-welded seam and fusion-bonded epoxy coating.
TransCanada to restart #Keystone pipeline on Tuesday. @nia_eleri reports: https://t.co/8eoSPVCNU7 $TRP pic.twitter.com/JEeu2Gcmpf
— Reuters Top News (@Reuters) November 28, 2017
TransCanada was operating a pipeline pig on the line at the time of the release, the report notes, but the pig did not detect leakage when it passed the spot where the rupture occurred. The PHMSA says there is no indication the tool contributed to the failure.
After metallurgical testing, TransCanada is required to perform a root-cause failure analysis within 90 days, to be submitted to the PHMSA.
Pipeline Permits
Officials with the South Dakota Public Utilities Commission said Thursday (Nov. 30) that they could revoke TransCanada’s license to operate the pipeline if violations of the company’s permit are uncovered.
The spill came just as TransCanada received its final state approval, from Nebraska, for the Keystone XL project, an extension of the Keystone line. Keystone XL had been rejected by the administration of former President Barack Obama in 2015, but in January, President Donald J. Trump invited the company to apply for federal permits again.
The company now has all of the necessary permits to move forward with the new pipeline, but has not committed to actually going through with construction. TransCanada is expected to make a final decision on Keystone XL soon, after analyzing demand.
Tagged categories: Coating failure; Fusion bonded epoxy; Mechanical damage; Oil and Gas; Pipeline; Pipelines; Quality Control
