A top Environmental Protection Agency official gave a presentation last year at a gathering of some of the most zealous deniers of climate science, highlighting the influence a small, fringe movement hawking crank theories now wields in Washington.

Emails HuffPost reviewed reveal Bill Wehrum, the EPA’s assistant administrator for air and radiation, gave a presentation in early February 2018 at an event organized by the Cooler Heads Coalition, an umbrella group of tax-exempt charities and right-wing nonprofits that includes some of the most ardent proponents of climate change denial.

Three other EPA officials ― associate administrator Tate Bennett, senior counsel David Harlow and then-spokeswoman Liz Bowman ― attended the confab with Wehrum, the emails show.

In an email dated Feb. 6, 2018, Myron Ebell, who has led the Cooler Heads Coalition for more than two decades, offered gratitude for the EPA officials’ attendance at the previous day’s event, and invited the group to the next meeting a month later.

“Thanks Bill, David, Liz, and Tate, for coming to Cooler Heads and for your presentation and taking questions, Bill. It was most useful,” Ebell, who led the Trump administration’s EPA transition team, wrote. “We look forward to seeing any or all of you at future meetings.”

The EPA declined to comment on the nature of Wehrum’s presentation and whether any officials attended other events with the Cooler Heads Coalition.

“EPA takes time to meet with stakeholders on a variety of regulatory issues, this is no different,” said EPA spokesman Michael Abboud.

Ebell did not respond to calls and text messages requesting comment.

The revelation is not surprising from an administration that’s attempting to eliminate or delay, by The New York Times’ estimate, at least 83 environmental regulations, particularly rules to curb climate pollution. The EPA is expected to announce a proposal next week to replace Obama-era power plants rules with a regulation that would, by the agency’s own estimates, allow for enough pollution to cause up to additional 1,400 premature deaths per year by 2030.

“The fact that Bill went to talk to a group like this is the cherry on top of a toxic sundae,” Joseph Goffman, a former senior counsel and associate administrator for climate who served in the Obama-era EPA, said by phone. “It’s the toxicity of the sundae that’s really going to have the damaging impact on people’s lives.”

But the emails show the degree to which top officials at the nation’s leading public health agency have cultivated chummy ties with “fringe conspiracy theorists,” the Sierra Club, which released the records obtained through a Freedom of Information Act request, said in a statement, calling the relationship “despicable.”

“It removes any illusion that the EPA is acting in good faith to ensure the public trust,” said Robert Brulle, an environmental sociologist at Drexel University.