Oil spill from Keystone Pipeline in South Dakota twice as big as first thought

ABERDEEN, S.D. — A crude oil spill from the Keystone Pipeline in South Dakota last November has turned out to be nearly twice as big as first reported.

Around 407,000 gallons (338,900 imperial gallons) spilled onto farmland when the pipeline broke near Amherst in Marshall County on Nov. 16, a spokeswoman for pipeline owner TransCanada Corp., told the Aberdeen American News. TransCanada had originally put the spill at 210,000 gallons (174,860 imperial gallons).

The new number would make the spill the seventh-largest onshore oil or petroleum product spill since 2010, as reported to the U.S. Department of Transportation.

READ MORE: Keystone pipeline leak in South Dakota likely caused by 2008 damage: report 

Repairs have since been made and the cleanup is done. TransCanada resumed using the pipeline 12 days after the leak.

“The remediation work on the property has been completed.

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“We have replaced the last of the topsoil and have seeded the impacted area,” TransCanada spokeswoman Robynn Tysver said in an email to the newspaper late Friday.

READ MORE: Keystone pipeline will reopen Tuesday after leak repaired

A preliminary report indicated that the pipeline might have been damaged during construction in 2008. The Pipeline and Hazardous Materials Safety Administration is expected to release its final report on the leak in the next few weeks. The federal agency has estimated that the leak cost TransCanada $9.57 million.

READ MORE: Keystone pipeline will reopen Tuesday after leak repaired

Brian Walsh, an environmental scientist manager for the state Department of Environment and Natural Resources, said the state received the corrective action order report from the pipeline agency about a week ago. He’s reviewing the 4,000 pages to verify the data and make any necessary changes before the final report is published.

The Keystone Pipeline carries oil more than 2,600 miles (4,180 kilometres) from Alberta, Canada, to Oklahoma and Illinois.