Many Americans have heard of the Keystone XL pipeline. Few have heard of Line 61.

Operated by Canadian energy firm Enbridge, Line 61 currently runs 560,000 barrels of tar sands oil a day between Superior, Wisconsin — where it connects to some of Enbridge's Canadian oil lines — and Pontiac, Illinois. This year, however, Enbridge hopes to continue the expansion of the line's capacity until it can eventually carry up to 1.2 million barrels per day — a 30 percent higher capacity than Keystone.

Last month, President Barack Obama vetoed a bill approving construction of Keystone in order to allow a lengthy State Department review to be completed. But because Line 61 doesn't cross an international border, it doesn't require the same kind of approval.

In many respects, the intense focus on Keystone — from both proponents and opponents — is symbolic. Canadian tar sands oil will be extracted and transported to the US whether or not Keystone's construction is approved. For starters, oil trains are able to transport oil when pipelines are unavailable. (While the size of the average pipeline spill is much greater than an oil train spill — pipelines transport far more oil — trains tend to have accidents more often. In the past month, four oil trains have derailed in Canada and the US.) Second and more significantly, there are pipeline alternatives to Keystone that are proposed or already exist. Like Line 61.

But despite the fact that Line 61 is poised to dwarf Keystone, and despite the fact it carries the same tar sands crude oil — it's been linked to increased pipeline corrosiveness due to the higher temperatures at which it's transported — Line 61 has received almost no national news coverage.

According to the Polaris Institute, a Canadian public interest research organization, between 1999 and 2010 Enbridge was responsible for more than 800 spills that dumped about 6.8 million gallons of oil. One of those spills was the 2010 Kalamazoo River oil spill in 2010, when the company's Line 6B released more than 1 million gallons near Marshall, Michigan. It was rated by the EPA as the "largest inland oil spill in Midwest history."

Enbridge monitors its lines for leaks from a control center in Edmonton, Alberta. Despite more than 16 alarms from the company's monitoring system, Line 6B spilled oil for 17 hours during the Kalamazoo incident. As it was designed to do, the pipe automatically went into local shutdown after the first alarm — but Enbridge technicians assumed the alarm was caused by an air bubble and restarted the line, pumping oil at higher pressure in hopes of clearing the presumed air bubble. By the time technicians realized there was, in fact, a leak, oil had saturated Talmadge Creek and was flowing into the Kalamazoo River.

The US National Transportation Safety Board later characterized Enbridge's employees as "Keystone Kops," stating that they had "failed to recognize their pipeline had ruptured and continued to pump crude into the environment." The agency also found that the spill had been caused by multiple "corrosion-fatigue cracks" that grew to create an 80-inch pipe breach. The cleanup of the Kalamazoo spill has cost Enbridge $1.21 billion.

"It is important to consider releases in the context of the industry and Enbridge's place in it," Kevin Jenkins, the company's senior advisor on public and government affairs, told VICE News. He pointed out that Enbridge has transported hundreds of millions of barrels of oil over the past decade through almost 15,000 miles of pipe, accounting for 10 percent of all US domestic crude. The company has successfully delivered "an average of 99.9993 percent" of its annual volume — 99.9997 percent if spills within Enbridge facilities are excluded. The company has also reported greatly improved safety measures since the Kalamazoo incident.

Still, Line 61 is unsettling many in Wisconsin.

The pipeline passes a few hundred yards from the home of Joe Rogzinski, a retired engineer who lives near Lake Superior in Marquette County. Just south of his home is Nina Creek, a tributary of the Fox River, which Line 61 passes over. The Fox River system is connected to some of the state's famous marshlands and wildlife refuges.

"If you were to take the Kalamazoo River spill and superimpose it here, that would wipe out our whole county," Rogzinski told VICE News. "People wouldn't notice what's going on until they saw an oil slick on a river, and there wouldn't be any way to stop it. [Enbridge] says that they have valves they can control from Edmonton, but… that didn't work in Kalamazoo."

Elizabeth Ward of the Sierra Club's Wisconsin branch is particularly concerned about Line 61's proximity to Lake Superior. "The Great Lakes are all connected, so if something really big happens, it could affect all of them," she said. "They provide drinking water for 42 million people."

Line 61, she points out, also passes through the St. Croix River, a National Scenic Riverway, at three different points. "As we learned with the Kalamazoo spill, we don't know how to clean up tar sands," she said. "It's been four and a half years, and there's still tar sands in the [Kalamazoo] river…. The EPA is continually ordering the dredging of the river, but they still can't get it out. If that happened in any of our important waterways, it would devastate Wisconsin."

To bump Line 61 to 1.2 million barrels per day, Enbridge needs to add or upgrade 12 pumping stations. Eleven have already been approved and are moving forward. The decision to approve the twelfth currently rests with a zoning committee in Wisconsin's Dane County, where the final station is located. However, the 2011 Pipeline Safety, Regulatory Certainty, and Job Creation Act federally pre-empts the authority of counties to deny permits. And so all that Dane County can really do is stall and hold out for a more comprehensive liability insurance policy from Enbridge to protect the county if there is a spill.

"We've heard a number of concerns from residents, but there's very little our committee can do," said Patrick Miles, the Dane County Board supervisor who chairs the zoning committee. "Applying any conditions to the permit that address preventing spills is outside our purview. The only thing in our authority is mitigating risk after a spill. If Enbridge were to go bankrupt and not have the means to pay for a cleanup of a spill, we're trying to make sure there's some financial means to fix that."

To that end, Dane County has hired an outside insurance consultant to assess what kind of insurance policy the county can take out to protect itself. David Dybdahl, the consultant they've chosen, previously helped to insure containment operations after the Chernobyl meltdown.

If the cost of insurance is too high, Enbridge could rethink the expansion, or the company could sue the county, arguing it has no legal right to attach insurance requirements to a zoning permit.

After the Kalamazoo spill, Jenkins says that Enbridge invested $4.4 billion in a new safety program, including a new control center in Edmonton. The lines are also scanned with technology Enbridge refers to as "smart pigs" — machines that travel inside pipelines in order to detect cracks or corrosion. The pigs send data back to Edmonton, where Enbridge can evaluate the information and dispatch work crews if necessary.

Nevertheless, in January 2014 a relatively minor 125-barrel spill occurred on Enbridge's Line 67, the "Alberta Clipper" pipeline. That line runs from Hardisty, Alberta to Enbridge's 450-acre Superior terminal, through which 15 percent of all daily US crude imports pass. There, along with Line 3, it joins and feeds Line 61. Enbridge plans to expand Line 67 to 800,000 barrels per day. The company is currently awaiting a US presidential permit to increase flow through the border segment of the pipeline, a delay that the State Department has called procedural.

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