The Keystone pipeline shut down on Nov. 16 after leaking 210,000 gallons of oil in South Dakota, just four days before Nebraska was due to make a decision on expanding the pipeline. (Reuters)

The Keystone pipeline running from Canada across the Great Plains leaked Thursday morning, spilling about 5,000 barrels of oil — or 210,000 gallons — southeast of the small town of Amherst in northeast South Dakota.

The spill comes just days before a crucial decision next Monday by the Public Service Commission in Nebraska over whether to grant a permit for a new, long-delayed sister pipeline called Keystone XL, which has been mired in controversy for several years. Both are owned by Calgary-based TransCanada.

The spill on the first Keystone pipeline is the latest in a series of leaks that critics of the new pipeline say shows that TransCanada should not receive another permit.

“TransCanada cannot be trusted,” said Jane Kleeb, head of the Nebraska Democratic Party and a longtime activist opposed to Keystone XL. “I have full confidence that the Nebraska Public Service Commission is going to side with Nebraskans, not a foreign oil company.”

TransCanada, which has a vast network of oil and natural gas pipelines, said that the latest leak occurred about 35 miles south of the Ludden pump station, which is in southeast North Dakota, and that it was “completely isolated” within 15 minutes. The company said it obtained permission from the landowner to assess the spill and plan cleanup.

Brian Walsh, an environmental scientist manager at the South Dakota Department of Environment and Natural Resources, said that the leaking pipe was in “either a grass or an agricultural field” and that TransCanada had people at the site. Walsh said the leak was detected about 5:30 a.m.

“Based on what we know now, the spill has not impacted a surface water body,” Walsh said. “It has not done that. So that’s good news.”

The first Keystone pipeline, which runs 1,136 miles from Hardisty in Alberta, carries about 500,000 barrels a day of thick bitumen from the oil sands area to pipeline, refining and storage networks in Steele City, Neb., and Patoka, Ill.

The pipeline has had smaller spills — 400 barrels each — in the same region in 2011 and 2016.

TransCanada told the Pipeline and Hazardous Materials Safety Administration that the May 7, 2011, spill at the Ludden pump station was caused by a threaded connection on small diameter piece of pipe that had been installed improperly, causing stress fatigue. There were two other small leaks at pumping stations that month.

In 2016, TransCanada told PHMSA that a third-party metallurgist it hired found a “small weld anomaly” that dripped at a slow rate for an indeterminate amount of time.

TransCanada first applied for a permit for its Keystone XL pipeline in 2008, but it has been delayed by environmental concerns. Some opponents said the pipeline would encourage the exploitation of the oil sands, whose extraction emits more greenhouse emissions than the extraction of other resources. President Obama approved the southern half of the project in 2012 but ultimately rejected the northern segment in late 2015.

After his election, President Trump issued an executive order to clear obstacles for the Keystone XL, but TransCanada still needed a permit from the independent, five-person Nebraska PSC. Concerns there have revolved around potential harm to the state’s ecologically delicate Sandhills region and its vast Ogallala aquifer, prompting TransCanada to move the Nebraska segment further east.

President Donald Trump on Friday unveiled his administration's official go-ahead for the Keystone XL pipeline, a controversial project that was rejected by his predecessor, former President Barack Obama. (Reuters)

TransCanada, by contrast, said the pipeline would be good for the economy and would create jobs.

Activists pounced on the news Thursday to renew their opposition to Keystone XL.

“This disastrous spill from the first Keystone Pipeline makes clear why Keystone XL should never be built,” said Jared Margolis, senior attorney with the Center for Biological Diversity. “Trump’s issuance of a permit for Keystone XL is a farce that will only lead to more pollution for people and wildlife.”

Read more at Energy & Environment:

As Trump administration grants approval for Keystone XL pipeline, an old fight is reignited

If Trump wants the pipes built in America, what does that mean?

Trump promised to build the Keystone XL. Three votes in Nebraska could stop it.

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