A Minnesota judge has made an official recommendation to state regulators that a proposed pipeline to carry tar sands crude oil across the state should follow an existing corridor through two Indian reservations—and not the path preferred by the operator, Enbridge Corporation.

The ruling complicates matters for the company, since it elevates the concerns of Native Americans who oppose the pipeline. The opponents said it gives them a better chance to fight the project.

Enbridge's proposed route, before the Minnesota Public Utility Commission, would skirt several reservations while traveling through a region rich in wetlands, wild rice lakes and watersheds critical to downstream drinking water supplies.

The judge's instructions, while not the final word, could strengthen the legal footing of tribes who have already come out in opposition to the project, because any pipeline passing through reservation land would require tribal approval.

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"We have not yet been freed from this, but we feel that there is some hope for our case and are very grateful to the judge and pray that the PUC makes the same decision," said Winona LaDuke, executive director of Native American environmental organization Honor the Earth.

The alternate route recommended by the judge would cross through the Leech Lake and the Fond du Lac reservations of northern Minnesota. In a 434-page "findings of fact, conclusions of law, and recommendation," Administrative Law Judge Ann O'Reilly made it clear that any new pipeline would require permission from those tribes.

"An approval of Route Alternative 07 does not, in any way, infringe on the sovereignty of the various Indian Tribes to disapprove permits or other approvals required for construction of the Project through land over which the Tribes maintain jurisdiction," O'Reilly wrote. "Just like the Commission cannot bind the federal government, the Commission does not have the authority to require the Indian Tribes to permit the replacement of Line 3 within the Reservations."

The state commission is expected to vote on the project in June.

Why Enbridge Opposes the Route

In its initial application with the PUC three years ago, Enbridge argued against the alternative route, which would require removing the existing Line 3 pipeline and laying the new Line 3 pipeline in its place.

The existing pipeline is flanked on either side by two to four other Enbridge pipelines along its route in northern Minnesota, complicating its removal and replacement. Enbridge proposed leaving the existing Line 3 in place and building the new pipeline elsewhere.

Citing added construction challenges, safety risks and oil shipment disruptions, the company concluded in its application that "this alternative is not a viable replacement option" to supplant the existing pipeline.

"It is an unavoidable reality that conducting heavy construction inside and over a multi-line pipeline corridor exposes the pipelines to risk that would otherwise not be present, thereby increasing the probability of damage," the company wrote. It said using the same trench for the new line would require taking the existing Line 3 out of service for up to two years.

O'Reilly, however, opposed abandoning the existing pipeline and cited public comments submitted to the PUC noting that abandonment could result in a risk of contamination and interference with property owners' use of the land.

O'Reilly's recommendation was not a total loss for the company. While the report rejected the company's preferred route, it did conclude that there is a need for the pipeline.

"Enbridge is pleased that the Administrative Law Judge has listened to the extensive evidence that there's need for this safety-driven maintenance project," the company said in a statement. "We will be taking time to review in more detail the recommendation that we use the existing right-of-way, and will have additional comments to follow."

Further complicating Enbridge's plans are expiring lease agreements on existing pipelines. Existing Enbridge pipelines that cross through the Leech Lake and Fond du Lac reservations have easements that expire in 2029 and will have to be renegotiated with the tribe.

Tribes Are Pushing Back on Pipelines

Tribes in the region, however, are increasingly pushing back, citing environmental concerns. The tribes are either demanding significantly more money to renew leases, from thousands of dollars in past decades to tens of millions of dollars in recent years, or declining to renew the leases entirely.

In February 2017, the Bad River Band of the Lake Superior Tribe of Chippewa Indians in northern Wisconsin voted not to renew an easement for Enbridge's Line 5 crude oil pipeline. In October 2017, the Lac Courte Oreilles Band of Lake Superior Chippewa in Wisconsin negotiated a roughly $60 million payment from Enbridge for a 25-year extension of an existing lease.

Earlier this year, the Red Lake Band of Chippewa in northern Minnesota rejected an $18.5 million offer from Enbridge to continue to allow a pipeline to pass through tribal land and voted to remove the pipeline from their land.

LaDuke said tribes in the region will be closely watching the PUC's upcoming decision and will continue to oppose any new pipelines on or near their reservations.

"The times have changed and 50 years of environmental contamination of our homeland is enough," LaDuke said.