The person responsible for overseeing the cleanup of the former nuclear weapons site in Hanford, Washington—the most contaminated in the United States—was fired on Tuesday after blowing the whistle on the dangerous conditions at the facility.

Donna Busche—manager of Environmental and Nuclear Safety for the San Francisco-based URS Corporation, a Hanford cleanup subcontractor hired by the federal government — is at least the third senior official who has been fired or forced out after raising the alarm about lack of safety at the site, according to the Los Angeles Times. She said executives told her she was being fired for “unprofessional conduct.”

“The Energy Department’s overall safety culture is broken and all they are doing now is sitting idly by,” Busche declared on Tuesday.

While URS claims Busche was not punished or retaliated against, Busche says she was “absolutely” targeted.

Busche, who had repeatedly charged that the clean-up company was steamrolling safety protections and ignoring dangerous technology flaws, had previously filed a lawsuit and a U.S. Labor Department complaint charging that URS was attempting to repress and fire her for speaking out.

“When people stand up and say something is unsafe and, as a result of that, they get fired, it sends a message to everyone else that to protect your career you should say nothing,” said Tom Carpenter, Executive Director for the watchdog organization Hanford Challenge, in an interview with Common Dreams.