TransCanada Corp’s Keystone pipeline has leaked an estimated 5,000 barrels (818,000 litres) of oil in north-eastern South Dakota, the company said on November 16.
The pipeline was shut down and emergency response procedures were activated after a drop in pressure was detected resulting from the leak south of a pump station in Marshall County, TransCanada said in a statement.
The South Dakota department of environment and natural resources, which has dispatched staff to the site, said it did not believe the leak onto agricultural land affected any surface water bodies or threatened any drinking water systems.
The pipeline transports crude from the Alberta oilsands in Canada, to refineries in Illinois and Oklahoma, passing through North and South Dakota, Nebraska, Kansas and Missouri. It can handle nearly 600,000 barrels daily. TransCanada says on its website that the company has safely transported more than 1.5bn barrels (245.4bn litres) of oil through the system since operations began in 2010.
TransCanada said in its statement that it expected the pipeline to remain shut down as the company responds to the leak.
A leak and spill in south-eastern South Dakota in April 2016 prompted a weeklong shutdown of the pipeline. TransCanada estimated that just under 77, 200 litres of oil spilled onto private land during that leak. Federal regulators said an “anomaly” on a weld on the pipeline was to blame. No waterways or aquifers were affected.
The Keystone Pipeline is part of a 2,687-mile system that will also include the proposed Keystone XL pipeline, which has faced persistent opposition from environmental groups, Native American tribes and some landowners.
President Donald Trump issued a federal permit for Keystone XL in March, after it had been blocked by the Obama administration. The Nebraska Public Service Commission is set to vote on the Keystone XL sequel on November 20 to clear the last major regulatory hurdle for the $8 billion project.
Keystone XL would route the pipeline on a more direct path through Montana and South Dakota to Nebraska, where it would connect with existing pipelines that feed Texas Gulf Coast refineries.
American environmental groups seized on the spill as evidence that their warnings against Keystone XL would come to pass.
“Just days before the Nebraska Public Service Commissions decides on whether to approve Keystone XL we get a painful reminder of why no one wants a pipeline over their water supply,” Canadian broadcaster CBC quoted Greenpeace campaigner Mike Hudema as saying.
In addition to the regulatory process in Nebraska, Keystone XL faces dwindling demand for oil that has already prompted TransCanada to cancel its biggest Canadian project, Energy East.