The Environmental Protection Agency's regional administrator for the Southeast has resigned after being indicted by a grand jury in Alabama for using his post for personal gain.

Onis “Trey” Glenn III, a Trump political appointee, announced his resignation on Sunday in a letter to EPA acting Administrator Andrew Wheeler.

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EPA chief of staff Ryan Jackson said on Monday that Wheeler accepted Glenn's resignation, while taking steps to install Mary Walker as acting head of the regional office. Walker is a former Georgia state environmental regulator.

Glenn was also the head of the Alabama state environmental office before coming to EPA. The basis of the indictment stems from his time working as the state's top environmental regulator, and not the federal EPA.

Glenn allegedly used his position in the state for personal gain and receiving compensation from groups he was meant to be regulating. He had consulted for the law firm Balch & Bingham on behalf of the Drummond company that was seeking to avoid cleaning up two waste sites in Alabama.

“As you know, unfounded charges have been levied against me that I must and will fight,” Glenn wrote in his resignation letter. "Stepping down now, I hope removes any distraction from you and all the great people who work at EPA as you carry out the agency’s mission.”

Glenn had come on board at the agency under former EPA Administrator Scott Pruitt, who resigned after months of allegations piled up that he was using his position in the Trump Cabinet for personal enrichment.