Massive pipeline spill caused by crack created during installation, third-party review concludes

Sierra Club official says flaws in Keystone pipeline mean it’s only a matter of time before another oil spill

By: - April 21, 2023 4:30 pm
Workers at the site of the oil spill from the Keystone pipeline near Washington, Kansas, in December 2022

Workers clean up at the site of the oil spill from the Keystone pipeline near Washington, Kansas, in December 2022. (Environmental Protection Agency)

LINCOLN — A third-party review of a pipeline spill that released 500,000 gallons of crude oil onto Kansas farmland and a nearby stream was caused by a crack in the metal pipe that eventually ruptured under pressure.

That was the conclusion of a third-party review that was ordered by a federal pipeline safety agency to investigate the December failure of the 36-inch Keystone pipeline, just south of the Nebraska border near Washington, Kansas.

It was the largest oil pipeline spill in the U.S. in nine years.

The “Root Cause Failure Analysis” for the so-called “Milepost 14 incident” reached the same conclusion as an independent analysis of the metal pipeline released in February.


Gary Salsman, vice president of field operations for TC Energy, testifies to a joint meeting of two Kansas House of Representatives committees on March 14, 2023, about a rupture on the Keystone pipeline that spilled almost 13,000 barrels of oil in northern Kansas. (Sherman Smith/Kansas Reflector)

‘Fatigue crack’

“The primary cause of the rupture was a progressive fatigue crack that originated at a girth weld connecting a manufactured elbow fitting to the pipe constructed across Mill Creek (in Kansas),” the operator of the pipeline, TC Energy, said in a news release Friday.

The company said that during construction of this segment of the Keystone pipeline, which as completed in 2011, “inadvertent bending stresses sufficient to initiate a crack” occurred on the elbow fitting.

Over time, and under the high pressure needed to push the oil down the pipeline, the crack worsened, eventually resulting in the leak.

The pipeline, which carries tar sands oil from Canada to refineries on the U.S. Gulf Coast, was operating at a pressure of 1,153 pounds per square gauge at the time of the Dec. 7 rupture, according to the federal Pipeline and Hazardous Materials Safety Administration.


Loren Drummond, reverend at Lyndon United Methodist Church, holds a sign reading “Water is life” during a vigil Feb. 6, 2023, at the Statehouse in Topeka
Loren Drummond, reverend at Lyndon United Methodist Church, holds a sign reading “Water is life” during a vigil Feb. 6, 2023, at the Statehouse in Topeka for the Keystone pipeline spill. (Chloe Anderson for Kansas Reflector)

‘Repetitious pattern of failures’

Since 2009, the Keystone pipeline has experienced three failures on similar girth welds, according to PHMSA.

In March, the agency ordered TC Energy to reduce the operating pressure to 923 ppsg on the segment of the Keystone pipeline from Steele City, Nebraska, to Cushing, Oklahoma, because of a “repetitious pattern of failures related to the original design, manufacture, and construction.”

On Friday, TC Energy, in a news release, said it had recovered 98% of the released product and cleaned up 90% of the shoreline of Mill Creek, where the failure occurred. Previously, the company has estimated its cost of responding and cleaning up the leak at $480 million.

Thousands of cubic yards of oil-soaked soil and other materials removed from the spill site were trucked to a landfill just outside Omaha.


Excavation, more inspections planned

TC Energy said that in response to the failure analysis, it plans to:

  • Excavate and investigate other Keystone pipeline sites with characteristics like the incident location.
  • Perform additional in-line inspections of the pipeline.
  • Review evolving pipeline design guidelines.


Oil covers parts of Bill Pannbacker's pasture following a rupture on the Keystone oil pipeline.
Oil covers parts of Bill Pannbacker’s pasture following a rupture on the Keystone oil pipeline. Keystone’s owner, TC Energy, has established a drone no-fly zone. (Submitted by Chris Pannbacker)

‘Only a matter of time’

The company said the latest review confirmed that the welding workmanship on the pipeline was “compliant with applicable codes and standards.”

A lobbyist with the Sierra Club of Kansas, however, said the latest report just reaffirms that there were flaws in original design, material and installation of the Keystone pipeline that make more oil spills inevitable.

“This shouldn’t give us any relief or assurance,” said Zack Pistora of the Sierra Club. “This only reaffirms that it’s only a matter of time before another weld fails or a design flaw causes another disaster.”

This story was produced by Nebraska Examiner, an affiliate of States Newsroom.

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Paul Hammel
Paul Hammel

Senior Reporter Paul Hammel has covered the Nebraska Legislature and Nebraska state government for decades. He started his career reporting for the Omaha Sun and was named editor of the Papillion Times in 1982. He later worked as a sports enterprise reporter at the Lincoln Journal-Star. He joined the Omaha World-Herald in 1990, working as a legislative reporter, then roving state reporter and finally Lincoln bureau chief. Paul has won awards from organizations including Great Plains Journalism, the Associated Press and Suburban Newspapers of America. A native of Ralston, Nebraska, he is vice president of the John G. Neihardt Foundation and secretary of the Nebraska Hop Growers.