Washington — Albert “Kell” Kelly, a top aide to Environmental Protection Agency chief Scott Pruitt who was hired to revitalize the agency’s cleanup of toxic sites, resigned on Tuesday amid scrutiny of his previous actions as the leader of a bank in Oklahoma and his lifetime ban from banking.

Kelly joined Pruitt at the EPA a year ago to head up a task force examining ways to improve and streamline the agency’s Superfund program. Around the same time, as part of a civil settlement, the Federal Deposit Insurance Corporation fined him $125,000, and it later banned him from banking altogether.

Kelly’s resignation was one of two high-profile EPA departures on Tuesday. The head of Pruitt’s personal security detail, Pasquale “Nino” Perrotta, also announced his retirement from the agency.

Perrotta faces congressional scrutiny for his role in Pruitt’s security arrangements, which have been more extensive than those of previous EPA administrators. He initially had planned to step down this summer but accelerated his retirement, officials said.

The resignations come as Pruitt faces multiple investigations by the agency’s inspector general. He is under scrutiny for ethics and spending issues, including renting a D.C. condo from a lobbyist at a below-market rate, installing a costly soundproof phone booth and spending millions on his personal security.

Pruitt praised Kelly and Perrotta in separate statements, saying that the latter had “selflessly served the American people for more than 23 years,” beginning as a special agent with the U.S. Secret Service.

Pruitt said Kelly had made a “tremendous impact” on the agency’s Superfund program, which aims to clean up hundreds of the nation’s most toxic sites. Kelly helmed a task force that issued recommendations to speed up those efforts.

“Kell Kelly’s service at EPA will be sorely missed,” Pruitt wrote.