About 5,000 barrels (210,000 gallons) of oil leaked 16 November from a section of the controversial Keystone Pipeline in South Dakota in the largest of three leaks from the pipeline in the state in the last two years.
According to a statement from pipeline operators Transcanada Corporation, crews “safely shut down its Keystone pipeline at approximately 6 a.m. CST (5 a.m. MST) after a drop in pressure was detected in its operating system resulting from an oil leak that is under investigation. The estimated volume of the leak is approximately 5,000 barrels. The section of pipe along a right-of-way approximately 35 miles (56 kilometres) south of the Ludden pump station in Marshall County, South Dakota was completely isolated within 15 minutes and emergency response procedures were activated”.
Officials don't believe the leak affected any nearby water bodies or drinking water systems, Brian Walsh, an environmental scientist manager at the South Dakota Department of Environment and Natural Resources told journalists.
"Ultimately, the cleanup responsibility lies with TransCanada, and they'll have to clean it up in compliance with our state regulations," Walsh said.
The pipeline will remain shut down as the company responds to the leak, but no timeline has been given for implementation of cleanup or repairs.
An April 2016 release spilled just 400 barrels of oil, Walsh said. Clean-up from that incident took approximately two months.
Thursday’s leak comes just days before Nebraska officials are scheduled to vote on whether to approve a 275-mile-long extension (Keystone XL, meaning “export limited”) of the project through that state. Nebraska’s approval is needed after President Donald Trump’s revival of the proposed extension which had previously been rejected by the Obama administration in 2015.
Keystone XL has become a focal point for protests by environmental activists and campaigners against fossil fuels.
"This is not the first time TransCanada's pipeline has spilled toxic tar sands, and it won't be the last," said Kelly Martin, director of the Sierra Club's "Beyond Dirty Fuels" campaign in a statement.
"There is no such thing as a safe tar sands pipeline, and the only way to protect Nebraska communities from more tar sands spills is to say no to Keystone XL…We've always said it's not a question of whether a pipeline will spill, but when, and today TransCanada is making our case for us."
Keystone has also attracted opposition from Native American groups in the US and Canada who are concerned about water contamination, pollution and potential damage to sacred sites.