Updated: 3:01 p.m. | Posted: 4 a.m.
The Minnesota Public Utilities Commission continued to wrestle Tuesday with how to balance the benefits of approving Enbridge's Line 3 oil pipeline project against the consequences of not approving the proposed line.
A key question that emerged in testimony was how long the current Line 3 would continue to operate if state regulators decide not to approve Enbridge's plan to replace the old line with a new pipe along a different route.
The existing line was built in the early 1960s. It's cracking, and corroding, and has spilled huge amounts of oil in the past — including the largest ever inland oil spill in the country in 1991 near Grand Rapids, Minn.
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Enbridge has reduced pressure on the line to keep it safe and meet federal requirements. But the company has estimated it would need to conduct more than 6,000 maintenance digs in the next 15 years to keep the line operating safely.
Enbridge attorney Christina Brusven told commissioners the company intends to continue operating Line 3 at least until the pipeline's easements across the Leech Lake and Fond du Lac reservations expire in 2029.
But Enbridge wouldn't give a definitive answer when pressed whether it would stop operating Line 3 in 11 years if the Leech Lake or Fond du Lac band asked them. "I don't think we have all the facts to do that at this time," Brusven said.
Several PUC commissioners appear conflicted over the benefits of approving a new pipeline, constructed with modern methods.
They agree that would reduce the risk of a major oil spill compared to the old line. But they also recognize a new pipeline along a different corridor would open up a new part of northern Minnesota to potential environmental damage.
It's also a difficult decision for the Leech Lake and Fond du Lac bands, said Fond du Lac attorney Seth Bichler.
Six Enbridge pipelines already cross both reservations, including Line 3. Most of those lines are aging, and will require increased maintenance work, Bichler said.
Enbridge's preferred new route for Line 3 avoids both reservations, but travels through ceded treaty territory where tribal members hunt, fish and gather and harvest wild rice. Bichler said a worst-case scenario would be a pipeline spill on that land, currently undisturbed by oil pipelines.
"We know more construction is coming to the reservation," said Bichler. "We can't avoid that. What we need is to preserve this area to the west and south. It makes no sense to put construction in both places."
Leech Lake band attorney Grace Elliott said the tribe has tried hard not to comment on the Enbridge replacement plan, and has instead focused on its desire to see Enbridge stop using the current Line 3 through its reservation.
"Whatever way will get Line 3 off the reservation the soonest" is the option the band supports, she told commissioners.
Commissioner Matt Schuerger said he'll be listening for potential modifications to Enbridge's preferred route that could bring the safety benefits of a new, modern pipeline, while also avoiding culturally important and environmentally sensitive areas, like Big Sandy Lake.
Other commissioners asked Enbridge if the company would consider a modification to its proposal to ship 500,000 barrels of oil a day across a new Line 3, instead of the proposed 760,000 barrels.
The company has reduced the pipeline's capacity to 390,000 barrels daily because of safety concerns.
"I think the answer is no," said Enbridge attorney Eric Swanson. Enbridge is proposing to build a new Line 3 not only to address safety concerns of the aging line, but also to address what's known as "apportionment," the rationing of space on the current pipeline to meet the demand of oil shippers.
"So anything less than 760,000 barrels per day," Swanson said, "necessarily the apportionment numbers would rise."
Commissioners are also discussing new commitments Enbridge made during proceedings last week in a bid to win approval of its project. Those commitments include a parental guarantee to cover cleanup costs in the event of a spill, and helping to fund a decommissioning fund to remove old pipelines in Minnesota.
Enbridge also reiterated its commitment to remove sections of the old Line 3 pipeline at the request of landowners or tribes, "assuming it can be safely done and we can get the permits," said attorney Brusven.