MADISON, Wis. (AP) — A federal appeals court has cleared the way for utilities to finish building a high-voltage power line across a Mississippi River refuge.

American Transmission Company, ITC Midwest and Dairyland Power Cooperative are in the final stages of constructing a 102-mile (164-kilometer) transmission line linking Iowa’s Dubuque County and Wisconsin’s Dane County. About a mile of the line (1.6 kilometers) would cross the Upper Mississippi River National Wildlife and Fish Refuge near Cassville, Wisconsin.

A coalition of conservation groups filed a federal lawsuit in March in hopes of stopping the crossing. The groups allege the U.S. Fish and Wildlife Service approved the crossing in February without adequate public comment. They also maintain that the agency and the utilities improperly reached a deal calling for the utilities to transfer land to the refuge in exchange for land within the refuge for the power line.

U.S. District Judge William Conley issued a preliminary injunction blocking the land swap while he weighs the merits of the case. A three-judge panel from the 7th U.S. Circuit Court of Appeals struck down the injunction on Thursday. The panel ruled that Conley didn’t find that the conservationists were likely to win the case, a mandatory determination to win a preliminary injunction.

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Online court records show Conley has set a briefing schedule on the merits of the case that extends through late July, with a hearing set for Aug. 8.

It’s unclear when the utilities might close the land deal and begin construction. Dairyland Power and ITC Midwest officials issued a joint statement Tuesday saying they were pleased with the 7th Circuit’s decision and they’re now free to complete the land exchange. The statement did not say when the utilities would close the deal and begin construction. ITC Midwest spokesperson Rod Pritchard said in response to a follow-up email from The Associated Press that the closing would happen “soon” and a construction schedule hasn’t been developed yet.

Tina Shaw, a spokesperson for the fish and wildlife service, declined to comment because the case is still pending in Conley’s court.

A public relations representative for Howard Learner, an attorney representing the conservationists, said she would try to schedule an interview with him.