Environmental activists are calling on senators to reject the nomination of former fossil fuel lobbyist David Bernhardt to lead the U.S. Department of the Interior.

The calls come ahead of the Senate Energy and Natural Resources Committee’s Thursday morning hearing to consider his nomination.

“David Bernhardt is a walking, talking conflict of interest,” said Alissa Weinman, a senior organizer for the nonprofit Corporate Accountability. “Between his Big Polluter ties and corporate lobbying connections, it’s clear Bernhardt will continue to serve the corporate interests to whom he owes his career, not the people or our public lands.”

Bernhardt has been under fire for his fossil fuel past since the Senate confirmed him as the agency’s deputy administrator in July of 2017. He currently serves as the department’s acting administrator, a position he has held since scandal-ridden Ryan Zinke resigned in December. President Donald Trump nominated Bernhardt to the permanent post last month.

“David Bernhardt heading the Interior Department would be a dream come true for fossil fuel companies, but a nightmare for the American people,” warned Greenpeace USA climate and energy campaign director Janet Redman.

Noting that “people who care about clean air, safe water, and a healthy climate have been sounding the alarm about Bernhardt’s history” for the past two years, Redman charged that “he’s done nothing since but prove he’s not fit for this job.”

A coalition of more than 160 conservation groups, including Greenpeace USA, sent a letter (pdf) to the chairman and ranking member of the Senate Energy and Natural Resources Committee, Sens. Lisa Murkowski (R-Alaska) and Joe Manchin (D-W.Va.), on Tuesday imploring them to oppose Bernhardt’s nomination:

In his 18 months serving as the Interior Department’s deputy secretary, Mr. Bernhardt has been at the center of a culture of corruption that has been the Interior Department’s hallmark under the Trump administration. He consistently puts private profit above the public interest, crafting policies to benefit past clients and rolling back longstanding rules to protect habitat, imperiled species, and public health. These actions come straight from the fossil fuel and mining industry’s wishlist, including some corporations for which Bernhardt used to work as a lobbyist and lawyer.

The letter outlines the ways in which Bernhardt has helped facilitate a siege on science, put fossil fuels first, imperil wildlife, promote development in the Arctic Refuge, harm national parks and monuments, and block transparency and oversight by Congress and the public.

Campaigners at various groups that signed on to the letter spoke out about Bernhardt’s record and urged senators to reject him.

Nicole Ghio of Friends of the Earth denounced Bernhardt as “a fossil fuel industry hack” while Leda Huta of the Endangered Species Coalition called him “a prime example of the culture of special-interest, big-money, influence peddling surrounding this administration.”

“His sorry record in protecting America’s natural resources, wildlife, and waters makes Bernhardt uniquely unfit for the job,” said John Bowman, managing director of government affairs at the Natural Resources Defense Council (NRDC).

Randi Spivak, public lands director at the Center for Biological Diversity (CBD), concluded that “Bernhardt has already shown us that he’s the most dangerous person to be in charge of our public lands and endangered species.”

Bernhardt has so many potential conflicts of interest due to his history as a lobbyist that, as the Washington Post revealed last year, he carries around a pocket-sized card listing all of them.

Public Citizen, another signatory of the letter, printed out a poster-sized version of the card and delivered it to senators voting on his confirmation. As the watchdog group put it, “An oil shill has no business overseeing our natural resources.”