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Nuclear Regulatory Commission Chairman Gregory Jackzo resigned today after a tumultuous tenure marked by criticisms of mismanagement and misconduct.

"After an incredibly productive three years as chairman, I have decided this is the appropriate time to continue my efforts to ensure public safety in a different forum," Jackzo said in a written statement. "This is the right time to pass along the public safety torch to a new chairman who will keep a strong focus on carrying out the vital mission of the Nuclear Regulatory Commission."

Jackzo, a physicist, had been accused of bullying his staff, withholding key information from the commission, and misogyny in the workplace.

"We believe that his actions and behavior are causing serious damage to this institution and are creating a chilled work environment at the NRC," Commissioners Kristine Svinicki, George Apostolakis, William Magwood and William Ostendorff wrote in a letter to the White House last year questioning Jaczko's ability to lead the agency.

"We are concerned that this will adversely affect the NRC's central mission to protect the health, safety and security of the American people," they wrote.

A former staffer for Senate Majority Leader Harry Reid, D-Nev., Jaczko was also a target for Republicans after the administration opted to abandon Nevada's Yucca Mountain nuclear waste depository. Reid has long-opposed the project.

During his tenure, Jaczko oversaw the U.S. response to the Japanese nuclear reactor crisis following the March 2011 earthquake and tsunami. He also approved permits for the first new nuclear power reactors in three decades.

Republicans today applauded Jaczko's decision to step down.

"The only thing surprising about his resignation is the fact that the Obama administration has remained silent for more than a year after allegations of Jaczko's offensive behavior surfaced," Senate Minority Leader Mitch McConnell, R-Ky., said. "Even Democrat commissioners said that Jaczko bullied employees and intimidated female workers as chairman of the commission."

Jaczko will continue to lead the agency until his successor is named.

"I will always be grateful for the opportunity of having served alongside the staff for all of these years, and for all that we accomplished together. I am looking forward to bringing all I have learned from my work and focus on safety at this agency with me as I move forward," he said.