Environmental Protection Agency Administrator Scott Pruitt speaks with auto industry leaders in Washington on Tuesday after signing a notice that he was scrapping the Obama administration’s car fuel standards. (Andrew Harnik/AP)

This post has been updated.

Scott Pruitt stepped to the lectern Tuesday in the Environmental Protection Agency’s ornate Rachel Carson Room, flanked by signs reading “certainty” and “confidence.” The words touted his rollback of Obama-era fuel efficiency standards, the latest move in Pruitt’s campaign to implement President Trump’s “deregulatory agenda.”

But the message of the signs seemed out of step with Pruitt’s current situation, as the EPA chief faces growing questions about a series of ethics decisions that have raised doubts about the job security of one of President Trump’s most effective Cabinet members.

In recent weeks, Pruitt has been the focus of ongoing scrutiny of his frequent first-class travel, which the EPA has argued was necessary because of security concerns. He now is facing inquiries over a discount condo rental he arranged with the wife of an energy and transportation lobbyist, as well as his decision to utilize an obscure provision of the Safe Drinking Water Act to give huge raises to two staff members.

On Tuesday, two Republican lawmakers joined a chorus of Democrats and environmental groups calling for Pruitt’s ouster. But Trump appeared to stand by his EPA chief, voicing support for a man who has also proven adept at delivering on the president’s campaign promise to aggressively roll back environmental regulations.

“I hope he’s going to be great,” Trump replied, when asked by reporters whether he still supports Pruitt.

Monday night, according to senior administration officials, Trump had called and told him, “Keep your head up, keep fighting. We have your back.”

Other Cabinet members have lost their jobs over controversies like Pruitt now faces, and history suggests that Trump’s support for him could change any day. Some close to the president say Pruitt is unpopular among senior White House aides and many of Trump’s friends. And Trump is closely attuned to news coverage — watching hours of it every day — and bad publicity has often soured him on a besieged staff member.

Senior Trump aides, including Chief of Staff John F. Kelly, have griped about Pruitt for several days, a senior White House official said late Tuesday. Kelly has told some colleagues he would like to see Pruitt gone, and the chief of staff has been annoyed by Pruitt floating his name to replace Attorney General Jeff Sessions. “But Trump isn’t there yet,” this person said.

At the EPA, according to several current and former top administration officials, the mood is growing darker. A few weeks ago, outside pundits were debating whether Trump would nominate Pruitt to replace Sessions; some now are speculating whether Pruitt will be forced to leave his current post.

The latest issue erupted Tuesday over Pruitt’s use of the water law to give the two aides substantial salary increases.

Barely three years ago, Millan Hupp worked at an Embassy Suites hotel near the Nashville airport. She now makes $114,590 as a top deputy to Pruitt, running his scheduling and advance operation. Weeks ago she got a 33 percent raise.

The pay hike came after the 26-year-old staffer oversaw an extensive housing hunt for the administrator last year. Hupp at times conducted the search during office hours, according to a former EPA employee and others who interacted with her, activity that ethics experts said constitutes a violation of federal rules.

Rep. Betty McCollum (Minn.), the top Democrat on the House Appropriations Subcommittee on Interior, Environment and Related Agencies, happened to live downstairs from Pruitt when he was renting the Capitol Hill condo — for which he paid $50 a night whenever he was in town. She faulted the administrator for operating under rules that would be untenable for an elected official.

“This is just corrupt,” she said. “I have a salary. I pay for a place to stay. And it would be a sweetheart deal if I only had to pay my mortgage on the days I’m there.”

Two moderate Republicans in Democratic-leaning House districts — Florida Reps. Carlos Curbelo and Rep. Ileana Ros-Lehtinen — called on Pruitt to step down. Curbelo tweeted that Pruitt’s “corruption scandals are an embarrassment to the Administration, and his conduct is grossly disrespectful to American taxpayers.”

Others came to his defense, including Sen. James M. Inhofe (R-Okla.), a longtime supporter.

“Administrator Pruitt has been instrumental in carrying out President Trump’s deregulatory agenda at the EPA,” Inhofe said in a statement. “I look forward to continuing to work with him to restore the EPA to its proper size and scope.”

One of the latest controversies was the housing agreement he struck with the health care lobbyist Vicki Hart, whose husband, J. Steven Hart, is chief executive of Williams & Jensen. The law firm lobbies on various energy, transportation and trade issues.

The Harts donated to Pruitt’s run for Oklahoma attorney general and held a fundraiser for him in 2014, according to public records.

“Vicki Hart purchased this property with the intention of eventually making it a residence for the Hart family,” said Ryan Williams, a spokesman for the couple. “In the interim, the property is used primarily for entertainment and occasional gatherings.”

EPA ethics officials hastily signed off on the unusual deal late last week after it became public, although they didn’t have all the details when they made their ruling.

Steven Hart told The Washington Post last week that he “had no lobbying contact with EPA in 2017 or 2018” and referred to Pruitt as a “casual friend” with whom he has had little contact. But according to several people with knowledge of that condo arrangement, Hart also talked proudly about the rental agreement with Pruitt.

After Pruitt left the condo last summer, Hupp spearheaded Pruitt’s subsequent moves. She contacted a local real estate firm to view properties for rent or sale, according to two individuals who spoke on the condition of anonymity for fear of retaliation.

Separately, according to Capitol Hill resident Laurie Solnik, Hupp contacted her via the website Zillow to inquire about an $1,800-a-month English basement apartment that Solnik was renting.

Part of Hupp’s search took place during office hours, according to these individuals. According to Don Fox, former acting director and general counsel for the Office of Government Ethics, it would amount to a violation of federal rules no matter when she worked on the project.

“There’s a general prohibition against misusing government resources, and employees are government resources,” Fox said. “It’s clearly personal, and frankly, it doesn’t matter if she did it 11 a.m. on a Tuesday or at 2 p.m. on a Saturday.”

In a statement, EPA spokesman Jahan Wilcox responded, “The notion that government resources were used to assist in finding housing is categorically false.”

Solnik said Hupp arranged for a viewing on a Friday afternoon and conveyed only minutes before Pruitt’s arrival that her boss was the prospective tenant. A member of the administrator’s round-the-clock security detail came and mentioned the prospect of parking Pruitt’s SUV in the back alley, she said.

Pruitt ultimately chose to live in the U Street area instead, then subsequently moved to an apartment on Capitol Hill where he now resides.

Hupp’s work for Pruitt dates back to early 2015, when she started as deputy finance director during his days as Oklahoma attorney general, according to her online résumé and LinkedIn page. Her duties then included hunting for new donors and serving as “on-the-ground orchestrator of activity” for his political travel.”

Around the same time, Hupp became a “financial and political consultant” for Pruitt’s two private fundraising vehicles, Liberty 2.0 Super PAC and Oklahoma Strong Leadership PAC. She solicited donations and scheduled his fundraising meetings and travel.

She declined to comment Tuesday.

The Atlantic first reported the raises for Hupp and EPA senior counsel Sarah Greenwalt, who also worked with him in Oklahoma. Greenwalt’s salary jumped more than 52 percent, from $107,435 to $164,200.

To hand out such raises, Pruitt used an obscure provision in the water law after the White House refused to boost the two women’s pay, according to two people with firsthand knowledge of the matter. The act allows the EPA chief to hire up to 30 people without presidential or congressional approval, which gave Pruitt the ability to set their salary levels himself.

Seung Min Kim, Julie Tate and Robert Costa contributed to this report.

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