In this May 16, 2018, photo, Environmental Protection Agency Administrator Scott Pruitt appears before a Senate Appropriations subcommittee on the Interior, Environment, and Related Agencies on budget on Capitol Hill in Washington. Pruitt claimed credit for pollution cleanups done mostly by the Obama administration while flubbing facts about his 2017 condo deal and blaming underlings for his ethical woes. (AP Photo/Andrew Harnik)
Andrew Harnik/AP
In this May 16, 2018, photo, Environmental Protection Agency Administrator Scott Pruitt appears before a Senate Appropriations subcommittee on the Interior, Environment, and Related Agencies on budget on Capitol Hill in Washington. Pruitt claimed credit for pollution cleanups done mostly by the Obama administration while flubbing facts about his 2017 condo deal and blaming underlings for his ethical woes. (AP Photo/Andrew Harnik)
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Environmental Protection Agency (EPA) Administrator Scott Pruitt testifies about the fiscal year 2018 budget during a Senate Appropriations Subcommittee on Interior, Environment, and Related Agencies hearing on Capitol Hill in Washington, DC, June 27, 2017. / AFP PHOTO / SAUL LOEB (Photo credit should read SAUL LOEB/AFP/Getty Images)
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EAST CHICAGO, IN - APRIL 19:  U.S. EPA Administrator Scott Pruitt makes a statement to the media after meeting residents from and taking a brief tour of the West Calumet Housing Complex on April 19, 2017 in East Chicago, Indiana.  Nearly all the residents of the complex were ordered to move by the East Chicago Housing Authority after the soil and many homes in the complex were found to contain high levels of lead. The area has been declared an EPA superfund site. This was Pruitt's first visit to a superfund site since being named the agency's administrator. The complex is scheduled for demolition.  (Photo by Scott Olson/Getty Images)
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EAST CHICAGO, IN - APRIL 19: U.S. EPA Administrator Scott Pruitt makes a statement to the media after meeting residents from and taking a brief tour of the West Calumet Housing Complex on April 19, 2017 in East Chicago, Indiana. Nearly all the residents of the complex were ordered to move by the East Chicago Housing Authority after the soil and many homes in the complex were found to contain high levels of lead. The area has been declared an EPA superfund site. This was Pruitt's first visit to a superfund site since being named the agency's administrator. The complex is scheduled for demolition. (Photo by Scott Olson/Getty Images)
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WASHINGTON, DC - JANUARY 18: Oklahoma Attorney General Scott Pruitt, President-elect Donald Trump's choice to head the Environmental Protection Agency, testifies during his confirmation hearing before the Senate Committee on Environment and Public Works on Capitol Hill January 18, 2017 in Washington, DC. Pruitt is expected to face tough questioning about his stance on climate change and ties to the oil and gas industry.   (Photo by Aaron P. Bernstein/Getty Images)
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WASHINGTON, DC - JANUARY 18: Oklahoma Attorney General Scott Pruitt, President-elect Donald Trump's choice to head the Environmental Protection Agency, testifies during his confirmation hearing before the Senate Committee on Environment and Public Works on Capitol Hill January 18, 2017 in Washington, DC. Pruitt is expected to face tough questioning about his stance on climate change and ties to the oil and gas industry. (Photo by Aaron P. Bernstein/Getty Images)
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EAST CHICAGO, IN - APRIL 19:  U.S. EPA Administrator Scott Pruitt makes a statement to the media after meeting residents from and taking a brief tour of the West Calumet Housing Complex on April 19, 2017 in East Chicago, Indiana.  Nearly all the residents of the complex were ordered to move by the East Chicago Housing Authority after the soil and many homes in the complex were found to contain high levels of lead. The area has been declared an EPA superfund site. This was Pruitt's first visit to a superfund site since being named the agency's administrator. The complex is scheduled for demolition.  (Photo by Scott Olson/Getty Images)
Scott Olson/Getty Images
EAST CHICAGO, IN - APRIL 19: U.S. EPA Administrator Scott Pruitt makes a statement to the media after meeting residents from and taking a brief tour of the West Calumet Housing Complex on April 19, 2017 in East Chicago, Indiana. Nearly all the residents of the complex were ordered to move by the East Chicago Housing Authority after the soil and many homes in the complex were found to contain high levels of lead. The area has been declared an EPA superfund site. This was Pruitt's first visit to a superfund site since being named the agency's administrator. The complex is scheduled for demolition. (Photo by Scott Olson/Getty Images)
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In this May 16, 2018, photo, Environmental Protection Agency Administrator Scott Pruitt appears before a Senate Appropriations subcommittee on the Interior, Environment, and Related Agencies on budget on Capitol Hill in Washington. Pruitt claimed credit for pollution cleanups done mostly by the Obama administration while flubbing facts about his 2017 condo deal and blaming underlings for his ethical woes. (AP Photo/Andrew Harnik)
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In this May 16, 2018, photo, Environmental Protection Agency Administrator Scott Pruitt appears before a Senate Appropriations subcommittee on the Interior, Environment, and Related Agencies on budget on Capitol Hill in Washington. Pruitt claimed credit for pollution cleanups done mostly by the Obama administration while flubbing facts about his 2017 condo deal and blaming underlings for his ethical woes. (AP Photo/Andrew Harnik)
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Mark Wilson/Getty Images North America/Getty Images
WASHINGTON, DC - MAY 16: EPA Administrator Scott Pruitt, testifies during a Senate Appropriations Subcommittee hearing on Capitol Hill, May 16, 2018 in Washington, DC. The Subcommittee is hearing testimony on the proposed budget estimates for FY2019 for the Environmental Protection Agency. (Photo by Mark Wilson/Getty Images)
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Environmental Protection Agency (EPA) Administrator Scott Pruitt testifies about the fiscal year 2018 budget during a Senate Appropriations Subcommittee on Interior, Environment, and Related Agencies hearing on Capitol Hill in Washington, DC, June 27, 2017. / AFP PHOTO / SAUL LOEB (Photo credit should read SAUL LOEB/AFP/Getty Images)
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WASHINGTON, DC - DECEMBER 7:  Environmental Protection Agency Administrator Scott Pruitt testifies before the House Energy and Commerce Committee about the mission of the U.S. Environmental Protection Agency on December 7, 2017 in Washington, DC.  (Photo by Pete Marovich/Getty Images)
Pete Marovich/Getty Images/FILE
WASHINGTON, DC - DECEMBER 7: Environmental Protection Agency Administrator Scott Pruitt testifies before the House Energy and Commerce Committee about the mission of the U.S. Environmental Protection Agency on December 7, 2017 in Washington, DC. (Photo by Pete Marovich/Getty Images)
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WASHINGTON, DC - JANUARY 18: Oklahoma Attorney General Scott Pruitt, President-elect Donald Trump's choice to head the Environmental Protection Agency, testifies during his confirmation hearing before the Senate Committee on Environment and Public Works on Capitol Hill January 18, 2017 in Washington, DC. Pruitt is expected to face tough questioning about his stance on climate change and ties to the oil and gas industry.   (Photo by Aaron P. Bernstein/Getty Images)
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WASHINGTON, DC - JANUARY 18: Oklahoma Attorney General Scott Pruitt, President-elect Donald Trump's choice to head the Environmental Protection Agency, testifies during his confirmation hearing before the Senate Committee on Environment and Public Works on Capitol Hill January 18, 2017 in Washington, DC. Pruitt is expected to face tough questioning about his stance on climate change and ties to the oil and gas industry. (Photo by Aaron P. Bernstein/Getty Images)
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 Environmental Protection Agency Administrator Scott Pruitt testifies before the House Energy and Commerce Committee's Environment Subcommittee in the Rayburn House Office Building on Capitol Hill April 26, 2018 in Washington, DC. (Chip Somodevilla/Getty Images)
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WASHINGTON, DC - NOVEMBER 17:  Environmental Protection Agency Administrator Scott Pruitt leaves after he spoke at an event November 17, 2017 in Washington, DC. Pruitt addressed The Federalist Society's 2017 National Lawyers Convention at the Mayflower Hotel.  (Photo by Alex Wong/Getty Images)
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WASHINGTON, DC - NOVEMBER 17: Environmental Protection Agency Administrator Scott Pruitt leaves after he spoke at an event November 17, 2017 in Washington, DC. Pruitt addressed The Federalist Society's 2017 National Lawyers Convention at the Mayflower Hotel. (Photo by Alex Wong/Getty Images)
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Republicans wants answers from EPA chief
(CNN) —  

Iowa Republican Sen. Joni Ernst on Tuesday called Environmental Protection Agency Administrator Scott Pruitt “as swampy as you get” for “transgressions” during his time leading the federal agency.

Ernst, who supported Pruitt’s nomination, called a biofuel mandate agreement negotiated by the White House a “bad deal” during an S&P Global Platts Energy Podium event in Washington, D.C., and said the EPA’s increased distribution of hardship waivers of the Renewable Fuel Standard diminishes biofuel demand.

“I am hopeful that the President will just recognize that Mr. Pruitt is breaking our President’s promises to farmers, and at some point he will say, ‘It’s time for you to go.’ But that’s up to the President to make that call. I will remain highly critical of Administrator Pruitt,” she said.

She added that “a number of other transgressions” related to his alleged misuse of agency funds to show “he is about as swampy as you get here in Washington, D.C.”

Pruitt currently faces about a dozen inquiries related to his actions leading the EPA. The probes are reviewing his travel expenses, personal security and other allegations of ethical concerns, such as Pruitt’s below-market-rate lease with a lobbyist couple, one of whom represented a client before the EPA.

Pruitt and the EPA have largely defended his actions, saying decisions were made by his subordinates and that, in some cases, “processes will be changed going forward.”

Ernst, speaking at the S&P Global Platts event, refused to call for Pruitt’s resignation or to block other EPA nominees.

Asked about Ernst’s comments as well as recent reports that Pruitt requested staff help him with personal tasks and organize a meeting with Chik-fil-a’s CEO to help his wife start a franchise, White House press secretary Sarah Sanders said, “We continue to have concerns and look into those. We’ll address them.”

CNN’s Gregory Wallace contributed to this report.