Environmental Protection Agency Administrator Scott Pruitt at the White House in February 2018. (Carolyn Kaster/Associated Press)

THIS MONTH, Environmental Protection Agency Administrator Scott Pruitt made it seem as though there was no official contact between himself and J. Steven Hart, the lobbying executive whose wife owned the condo in which Mr. Pruitt resided for six months in 2017. “Mr. Hart has no client that has business before this agency,” Mr. Pruitt insisted on Fox News, attempting to justify the extremely easy terms on which he rented his Capitol Hill residence. But Mr. Hart acknowledged over the weekend that Mr. Pruitt met with him at the EPA last July, while the administrator was still living in the condo.

Not only does this revelation enhance the case that the administrator committed serious ethical lapses while running a major Cabinet agency, but it also fits into a broader pattern of advantage-taking that Mr. Pruitt began before he ever arrived in Washington.

According to Mr. Hart, he accompanied a friend to the EPA to meet with Mr. Pruitt about Chesapeake Bay cleanup. That friend, Dennis Treacy, serves on the board of the Chesapeake Bay Commission, which advises Mid-Atlantic leaders on revitalizing the nation’s largest estuary. The lobbyist said that he did not take any money for his time. Maybe these circumstances enable Mr. Hart and Mr. Pruitt to claim no official lobbying took place between the two. Yet even if Mr. Hart did not say a word, his presence was still inappropriate. Mr. Hart should have recognized how suspicious this would have looked. But Mr. Pruitt was the one in a position of public trust, and it was on him to refuse any kind of official meeting with Mr. Hart in attendance, knowing that he would go home later that night and sleep in a condo owned by Mr. Hart’s wife and rented to him on terms so generous they amounted to a favor. It also would have been seemly to disclose the meeting in the first place.

This would not be the first time Mr. Pruitt has benefited from relationships with wealthy notables involved in issues related to his official duties. The New York Times reported Saturday that, when he was attorney general in Oklahoma, Mr. Pruitt gave state contracts to a law firm run by Kenneth Wagner, an old friend and business partner. The two had bought a luxurious Oklahoma City house together in a complicated transaction that involved a major telecommunications company and ended up profiting them handsomely. That telecommunications firm won kind treatment from Mr. Pruitt’s office. Mr. Pruitt also bought a minor league baseball team with a staffing company boss whose interests he pushed in the state legislature.

The more Mr. Pruitt’s past and present behavior comes to light, the swampier it looks. And this says nothing about the science-denying agenda he has pursued at the EPA. He should never have been tapped to lead the agency. Now that he has proved unethical as well as unwise, it is long past time for him to leave.