WASHINGTON — Days after the Senate confirmed him as administrator of the Environmental Protection Agency, Scott Pruitt appeared at the Conservative Political Action Conference and was asked about addressing a group that probably wanted to eliminate his agency.

“I think it’s justified,” he responded, to cheers. “I think people across the country look at the E.P.A. the way they look at the I.R.S.”

In the days since, Mr. Pruitt, a former Oklahoma attorney general who built a career out of suing the agency he now leads, has moved to stock the top offices of the agency with like-minded conservatives — many of them skeptics of climate change and all of them intent on rolling back environmental regulations that they see as overly intrusive and harmful to business.

Mr. Pruitt has drawn heavily from the staff of his friend and fellow Oklahoma Republican, Senator James Inhofe, long known as Congress’s most prominent skeptic of climate science. A former Inhofe chief of staff, Ryan Jackson, will be Mr. Pruitt’s chief of staff. Another former Inhofe staff member, Byron Brown, will serve as Mr. Jackson’s deputy. Andrew Wheeler, a fossil fuel lobbyist and a former Inhofe chief of staff, is a finalist to be Mr. Pruitt’s deputy, although he requires confirmation to the position by the Senate.