If Scott Pruitt’s tenure at the helm of the Environmental Protection Agency can be likened to an ecological disaster—and according to conservationists, it can—then the confirmation on Thursday of a longtime energy lobbyist to serve as Pruitt’s number-two is the Exxon Valdez .

Should the scandal-plagued Pruitt be forced from his seat at the head of the EPA, newly minted deputy administrator Andrew Wheeler stands to inherit his position as head of the government agency tasked with enforcing environmental laws. In effect, Pruitt’s downfall could lead to the EPA being run by a climate-change denialist who has raked in millions in lobbying fees on behalf of polluters the EPA was created to regulate—and who in his spare time has publicly defended controversial alt-right figures by citing online conspiracy theorists.

Wheeler started his career at the EPA in the nearly 1990s, drafting guidelines for the Office of Pollution Prevention and Toxics. But his growing influence in Washington began on Capitol Hill, where he worked for more than a decade and eventually rose to become chief of staff for Senator James Inhofe (R-OK). Inhofe, who once brought a snowball onto the Senate floor to illustrate the “hysteria on global warming,” has been a vocal cheerleader of Wheeler’s nomination, declaring that “there is no one more qualified than Andrew to help Scott Pruitt restore EPA to its proper size and scope.”

For most of the past decade, however, Wheeler plied his experience in environmental regulation to work on behalf of the energy and chemical industries. As a principal at Faegre Baker Daniels Consulting, his clients have included the nuclear power industry, importers of natural gas, chemical giants accused of dumping toxins in drinking water, and the nation’s largest coal mining company—all businesses that have had past entanglements with federal regulators, and likely would continue to if Wheeler became the head of the EPA.

Wheeler has notably advocated on behalf of uranium mining company Energy Fuels Resources Inc., which successfully lobbied the Trump administration last year to shrink Bears Ears National Monument by more than 1.1 million acres, or 85 percent of its original size. The move, the largest reduction of federally owned lands in American history, opened the uranium-rich land up for mining. Other clients include ICOR International, a refrigerant manufacturer which hired Wheeler to lobby the EPA for weaker ozone regulations, and chemical manufacturer Celanese Corporation.

But Wheeler’s largest benefactor has been coal giant Murray Energy, the largest coal company in the nation. A review of lobbying disclosures by The Daily Beast found that during his time at Faegre Baker Daniels, Wheeler became the point man for the coal mining behemoth, bringing in at least $3,324,000 in lobbying fees from Murray Energy alone. Murray Energy has sued the EPA on multiple occasions, most notably in an attempt to block the enforcement of carbon emissions restrictions.

Asked how the EPA plans to ensure that Wheeler’s past work wouldn’t color his role as deputy administrator, EPA spokesperson Liz Bowman told The Daily Beast that Wheeler “ has not lobbied [the] EPA, nor any new EPA issues since President Trump was elected,” noting that Wheeler deregistered as lobbyist in August 2017, shortly before his nomination.

“Mr. Wheeler consults with EPA career ethics officials, and will ensure that he is recuses himself from any potential conflicts,” Bowman said.

While Wheeler may not have lobbied the EPA, however, he did attend a March 2017 meeting between Energy Secretary Rick Perry and the chief executive officer of his largest benefactor at Faegre Baker Daniels: Robert Murray, of Murray Energy. During that meeting, Murray provided Perry with a proposal that would provide special government subsidies to coal and nuclear power plants—and gave the secretary a controversial bear hug.

Wheeler’s record has terrified conservationists, particularly after Pruitt’s escalating ethics scandals have put his future as administrator in jeopardy.

“The mission of the EPA is to protect human health and the environment, but Andrew Wheeler has dedicated his career to weakening environmental protections, serving as a lobbyist for numerous fossil fuel clients, including one of our country’s biggest polluters, Murray Energy,” said Gene Karpinski, president of the League of Conservation Voters, in an open letter to the Senate ahead of Wheeler’s confirmation. “Wheeler’s inherent conflicts of interest from his long history of ties to the fossil fuel industry make him an entirely inappropriate choice for EPA’s number two leadership role.”

Wheeler did not respond to a request from The Daily Beast to discuss his work with Faegre Baker Daniels, but Bowman did direct The Daily Beast to the Office of Government Ethics, which has published a letter from Wheeler to the agency’s career ethics official in which he vows to abide by his ethical commitments.

In some ways, Wheeler’s work is in keeping with the EPA’s agenda under President Trump’s banner of regulatory reform. But Wheeler hasn’t always been a fan of Trump: In a six-point February 2016 Facebook post, Wheeler told his followers that Trump was a “bully” who “doesn’t understand how the government works.”

Only seven months later, however, Wheeler had swung hard in the direction of some of Trump’s most fervent fans. In August 2016, Wheeler publicly defended alt-right troll Milo Yiannopolous after the latter was banned from Twitter for encouraging users to harass actress Leslie Jones. In a now-deleted tweet, the lobbyist linked to a six-minute video, “The Truth About Milo,” produced by InfoWars editor-at-large and noted conspiracy theorist Paul Joseph Watson, in which Watson posited that conservatives might be “banned from using the internet altogether if they trigger your butthurt.”

Pruitt, for his part, has welcomed Wheeler into the fold at EPA with open arms.

“Andrew Wheeler has spent his entire career advancing sound environmental policies and I look forward to him bringing his expertise and leadership to the agency,” Pruitt said in a statement upon Wheeler’s confirmation. “I look forward to working with Andrew to implement President Trump’s environmental agenda.”