A federal judge has ordered energy company Enbridge Inc. and an American Indian tribe to come up with an emergency plan to prevent potential spills from an aging oil pipeline running across the tribe’s reservation.

The Bad River Band of Lake Superior Chippewa sued Enbridge in federal court in 2019 to force the company to remove a section of the Line 5 pipeline that runs across the tribe’s reservation in northern Wisconsin, arguing the nearly 70-year-old line poses an unreasonable risk to health and safety. The company agreed and plans to build a $450 million pipeline that would run 41 miles (66 kilometers) around the reservation.

Wisconsin Public Radio reported that U.S. District Judge William Conley said in an order issued Monday that risk of a significant rupture exists and the resulting spill could cause “catastrophic” impacts to the Bad River watershed. He allowed the pipeline to continue operating but ordered the tribe and the company to develop a plan to prevent possible spills.

He told the company and tribe to meet and talk about installing emergency shutoff valves and developing a protocol for shutting down and purging the line by Dec. 17. They must submit proposals by Dec. 24.

Enbridge spokesperson Juli Kellner said in a statement that the company looks forward to meeting with the tribe. Bad River tribal Chairman Mike Wiggins Jr. didn’t immediately respond to a request for comment on Monday.

Sierra Club Wisconsin Director Elizabeth Ward said she’s glad that Conley recognized the tribe’s concerns about a potential spill but she’s disappointed the judge didn’t shut down the line.

Conley has said a shutdown would have significant effects on regional economies. Line 5 carries up to 23 million gallons (about 87 million liters) of oil and natural gas liquids daily and stretches 645 miles (about 1,040 kilometers) from Superior through northern Wisconsin and Michigan to Sarnia, Ontario.