You've probably heard of the Keystone XL pipeline. But what about Line 67, also known as the Alberta Clipper?

Nine years ago, both were controversial proposals to ship oil from Canada's tar sands into the United States. But while Keystone XL is still awaiting approval and continues to draw protests, Line 67 quietly secured a federal permit last week to ship even more crude than Keystone would.

On Oct. 13, the State Department approved a long-awaited permit that allows Enbridge, which owns the pipeline, to pump up to 890,000 barrels per day across the border between Canada and North Dakota, en route to Superior, Wisconsin.

"Enbridge has built the equivalent of a Keystone XL pipeline without gaining the kind of attention that Keystone got," said Kenneth Rumelt, a senior attorney and professor at Vermont Law School who represented several environmental and indigenous groups in a challenge to the project. "Other than our suit, it largely slipped under the radar. But really, this is a quiet Keystone XL pipeline."

Even before the approval, though, the company had already effectively been shipping the full volume through a clever work-around.

It's a convoluted story that reflects how Enbridge has gone about trying to boost its capacity to ship Canadian tar sands crude to U.S. refineries piece by piece.

Boosting Line 67's Volume Before the Permit

Enbridge began construction on Line 67 in 2008, designing it to eventually carry up to 890,000 barrels per day. Yet when the company initially applied to ship oil over the border, it requested approval to ship about half that amount, 450,000 barrels per day. Enbridge got that approval in 2009, about the time opposition to Keystone XL began gaining steam.

By the time Enbridge asked to expand its shipments to the full volume, in 2012, the opposition to new pipelines had strengthened. President Barack Obama had already issued his initial rejection of Keystone XL, and Enbridge's application stalled.

Enbridge was, however, allowed by the State Department to connect Line 67 to a parallel pipeline—Line 3—which was already permitted to ship the full volume.

"It kind of got what it wanted by moving the additional oil" across the border through Line 3 before switching it back to Line 67, said Anthony Swift, director of the Canada project at the Natural Resources Defense Council.

Several indigenous and environmental groups challenged the arrangement, but lost in court. With the Trump administration's approval of the expanded Line 67 permit, Enbridge no longer needs the work-around.

"There is no real change to what we're doing," said Jesse Semko, an Enbridge spokesperson, in an email. "We have been effectively utilizing the full capacity of Line 67 using an interconnection."

Enbridge Now Wants to Expand Line 3

The effect is that last week's approval will not result in any more oil flowing across the border—at least not yet. Enbridge is also seeking to expand capacity on Line 3. The fate of the Line 3 expansion now lies in the hands of state officials in Minnesota.

Swift said the approval highlights the Trump administration's determination to move forward with energy projects regardless of their impact on the climate. The permitting process for Line 67 showed that the tar sands oil it will ship generates about 21 percent more carbon dioxide emissions than the average refinery mix.

Enbridge is seeking to expand Line 3, an old pipeline that is currently operating with a capacity of 390,000 barrels per day, to carry up to 760,000 barrels per day. Last month, however, officials in Minnesota, who need to sign off on the project, said there's no need for the additional capacity, and that the pipeline isn't worth the risks of a spill. The state's Public Utilities Commission will hold a series of hearings on the project next month.