Two activist groups have told Interior Secretary David Bernhardt to expect a lawsuit if he further extends the temporary assignments of William Perry Pendley as head of the Bureau of Land Management and David Vela as head of the National Park Service.

Public Employees for Environmental Responsibility and the Western Watershed Projects wrote to Bernhardt Tuesday to threaten the legal action if he extends their assignments to run those agencies past May 5, when their current assignments run out.

The groups say Bernhardt illegally put the two in charge in violation of the Federal Vacancies Reform Act.

Both Pendley and Vela are deputy directors of their agencies, exercising the authority of the director as assigned by Bernhardt.

Pendley was first put in charge of the BLM last summer by Bernhardt, with his stint running the agency since having been extended by Bernhardt multiple times.

In that capacity Pendley has been overseeing the BLM’s relocation of its national headquarters from Washington, D.C., to Grand Junction, where the BLM opened the doors to its new national office in January.

Appointees to directorships of agencies such as the BLM and National Park Service requires Senate confirmation. The two groups say in their letter to Bernhardt that the president can appoint acting directors temporarily and according to strict conditions under the Federal Vacancies Reform Act, but President Trump never has done so, and neither Pendley nor Vela are otherwise qualified under the act to be acting directors under that law’s provisions.

They say a March ruling by Judge Randolph Moss in the U.S. District Court in the District of Columbia supports their argument.

Moss struck down immigration actions taken by Ken Cuccinelli while exercising the authority of director of the U.S. Citizenship and Immigration Services, ruling that his designation to run the agency was in violation of the act.

“Much of the reasoning that invalidated Mr. Cuccinelli’s actions in his position applies to Mr. Pendley’s and Mr. Vela’s positions as well,” the two groups say in their letter to Bernhardt.

Erik Molvar, executive director of the Western Watersheds Project, said Tuesday, “The Cuccinelli case could very well be the thread that proves the unraveling of the Trump administration’s scheme to keep these unconfirmed appointees at the heads of major federal departments.”

He said that in the case of the BLM, it seems obvious that the Trump administration doesn’t want to nominate a qualified director candidate who would survive a nomination fight in the Senate.

Molvar says Pendley never was an agency professional.

He was put in charge of the BLM immediately after being hired as a deputy director.

Pendley previously had a long career running the Mountain States Legal Foundation.

He was “basically an attorney for one of the biggest law firms that works to undermine conservation on public lands,” Molvar said.

He contends that Pendley has continued to undermine conservation while running the BLM.

Interior spokesman Conner Swanson said in an email Tuesday, “As we continue to address this national emergency, these special interest groups would rather seek to divert critical taxpayer resources on a baseless lawsuit and attempt to remove the leaders of critical government bureaus. Mr. Pendley and Mr. Vela are providing crucial leadership, and the Department is grateful for their service.”

Kathleen Sgamma, president of the Western Energy Alliance oil and gas trade association, said the challenge of Pendley’s assignment by the two groups isn’t surprising.

“They don’t like Mr. Pendley because he’s effective and doesn’t buy into their agenda of opposition to balanced, productive uses of public lands,” she said.

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