Environmental and Alaska Native groups asked a federal court in Anchorage on Dec. 15 to stop the U.S. Interior Department from opening the Arctic National Wildlife Refuge (ANWR) to oil and gas exploration before President Donald Trump leaves office next month.

Four lawsuits have been filed since August challenging the Trump administration’s plans to auction drilling rights, or lease sales, in the ecologically sensitive but potentially energy-rich coastal plain of ANWR along the Beaufort Sea.

The plaintiffs in three court cases filed motions on Dec. 15 seeking a preliminary injunction to block the lease sales, which the Interior Department has said it intended to hold by Jan. 6.

They also have requested a court order barring permits sought for seismic operations, which can involve blasting to produce sonic images of underground formations, within 352,400 acres of the refuge’s 1.6 million-acre coastal plain.

Opponents of such activities, which would begin ahead of actual drilling, say they would prove especially disruptive to resident populations of polar bears listed as a threatened species due to climate change. The U.S. Fish and Wildlife Service has said seismic disturbances to bears would be minimal.

If granted, the plaintiffs’ motions could delay any decisions about the pristine region until after the Jan. 20 inauguration of President-elect Joe Biden, who opposes drilling there. Opponents of energy exploration in ANWR have requested a decision by the court before the planned lease sales are held.

“It is hardly surprising that these special interest groups and frequent filers are trying to stop a Congressionally-mandated energy development program,” Department of Interior Spokesman Ben Goldey said in an email, adding that the administration’s program “includes extensive protections for wildlife.”

Groups suing include the National Audubon Society, Center for Biological Diversity, Friends of the Earth, the Natural Resources Defense Council (NRDC) and three Gwich’in tribal governments.

They argue that the lease sales would pave the way for irreparable damage to a pristine tundra ecosystem that is vital to wildlife including polar bears and caribou, and that the federal government failed to adequately analyze greenhouse gas emissions from potential drilling in the area.

In court filings, drilling opponents cited a decision earlier this month by the 9th U.S. Circuit Court of Appeals that canceled approval of what could become the nation's first offshore oil production facility in federal Arctic waters.

In that decision, the court found that the Department of Interior had failed to account for increased carbon emissions overseas when it approved the project.

Drilling had been banned in ANWR for decades before Republican-led tax legislation signed by Trump in 2017 removed the prohibition. Trump has sought to maximize domestic oil, gas and coal production and has downplayed environmental threats posed by drilling and mining industries.