John Konkus, EPA's deputy associate administrator for public affairs, repeatedly reached out to senior staffers at the Heartland Institute, according to the emails.
"If you send a list, we will make sure an invitation is sent," Konkus wrote to then-Heartland president Joseph Bast in May 2017, seeking suggestions on scientists and economists the EPA could invite to an annual EPA public hearing on the agency's science standards.
Follow-up emails show Konkus and the Heartland Institute mustering scores of potential invitees known for rejecting scientific warnings of man-made climate-change, including from groups like Plants Need CO2, The Right Climate Stuff, and Junk Science.
The emails underscore how Pruitt and senior agency officials have sought to surround themselves with people who share their vision of curbing environmental regulation and enforcement, leading to complaints from environmentalists that he is ignoring the conclusions of the majority of scientists in and out of his agency especially when it comes to climate-changing carbon emissions.
They were obtained by the Environmental Defense Fund and the Southern Environmental Law Center, which sued to enforce a Freedom of Information request and provided them to The Associated Press.
The EPA maintains close working relationships with a broad range of public and private groups, and Heartland is just one of many the agency engages with "to ensure the public is informed," said EPA spokesman Lincoln Ferguson.
"It demonstrates the agency's dedication to advancing President Trump's agenda of environmental stewardship and regulatory certainty," he said.
The public hearing referred to in the May 2017 email ultimately was canceled when the EPA official who runs it fell ill, the EPA said.
But Bast contended in an email sent to EPA staffers and others that the official called off the hearing after learning that climate-change "skeptics planned to attend."
The Heartland Institute calls itself a leading free-market think-tank. It rejects decades of science saying fossil-fuel emissions are altering the climate and says on its website that curbing use of petroleum and coal to fight climate change would "squander one of America's greatest comparative advantages among the world's nations."
"Of course The Heartland Institute has been working with EPA on policy and personnel decisions," Tim Huelskamp, a former Kansas Republican congressman who now leads the group, said in a statement to the AP.
"They recognized us as the pre-eminent organization opposing the radical climate alarmism agenda and instead promoting sound science and policy," Huelskamp wrote.
He said Heartland would continue to help Pruitt and his staff.
Ferguson said Pruitt and his top officials have also met with groups known for their campaigns against climate-changing emissions and pollutants from fossil fuels, including the Moms Clean Air Force, the American Lung Association, and others.
But Ben Levitan of the Environmental Defense Fund said mainstream climate-change groups have received nothing like the outreach and invitations that Heartland and other hard-right groups have been getting.
Certainly, "in some ways this is normal and in the course of business that ebbs and flows with the ideology of the administration in power," said Meredith McGehee, executive director of Issue One, a non-profit promoting ethical government and bipartisan political reform.
Heartland is not registered as a lobbying group. Spokesman Jim Lakely said the group has logged its contacts with EPA and that they fall below the level required for disclosing as lobbying.
An email last February shows Bast forwarded to followers an email with the line "From the White House," rallying activists to public hearings the EPA was then holding around the country on repealing an Obama-era power plan meant to curb fossil-fuel emissions.
The email is signed by a Pruitt political appointee and gives the name of another EPA official for activists to call. It's not clear from the email, however, who initiated the attempt to rally conservatives for the public hearing.
Konkus was a Republican political consultant when Pruitt named him to the agency. His duties include reviewing awards of hundreds of millions of dollars in federal grants. The Washington Post reported in September that Konkus had been scrutinizing grant applications for mentions of climate change, which he reportedly calls "the double C-word."
Emails show he and former EPA spokeswoman, Liz Bowman, repeatedly reached out to Heartland to talk over critical coverage by the Post.
Lakely, the Heartland spokesman, responds he's shared the article with colleagues, "asking them to jump to your aide (sic) and defend this position."
Konkus also contacted Heartland and other conservative groups asking for what he calls "echo" amplifying word of Pruitt's regulation-cutting efforts, according to the emails.
And an email from Bast, shared with EPA staffers and others, shows the then-Heartland president celebrating news that a reporter, Justin Gillis, was leaving The New York Times.
"Ding Dong, the Witch is Dead . Still waiting for Chris Mooney and Juliet Eilperin at the WaPo and Seth Borenstein at AP to flame out," Bast writes.
Spokespeople for the AP, The Washington Post and The New York Times declined comment.
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