The support of a powerful patron, Senate Majority Leader Harry Reid (D-Nev.), put Gregory Jaczko at the helm of the Nuclear Regulatory Commission, giving Jaczko the opportunity to lead a historic review of the safety of U.S. reactors following last year's disaster at Japan's Fukushima Daiichi nuclear complex.

Now, as Jaczko prepares to leave NRC, his immediate legacy is dominated less by the list of new safety actions the commission initiated and enacted during his nearly eight years on NRC and more by partisan congressional debate that began with his actions to kill Reid's personal anathema -- the planned Yucca Mountain nuclear waste repository in Nevada.

While the NRC post-Fukushima review is leading to a series of new reactor safety defenses, Jaczko was increasingly isolated from the other four NRC commissioners -- two Democrats and two Republicans -- in a split that started over Yucca Mountain.

Jaczko, 41, announced his intention to resign the NRC post yesterday, ahead of an anticipated report by the agency's inspector general that is expected to reopen complaints that Jaczko bullied fellow commissioners and staff. His statement made no mention of those charges, which he has denied. It simply declared that this was "the right time" to turn the job over to someone else.

Reid saluted Jaczko in a statement yesterday, saying, "Greg was my trusted aide for many years and his talent in applying science to public policy was an asset to my staff and the state of Nevada. I wish him well in his future endeavors."

"I am confident whomever replaces Chairman Jaczko will share his commitment to protecting the safety of the American people over the interests of a single industry," Reid said.

Senior House and Senate Republicans have mounted a take-no-prisoners campaign against Jaczko that also began with the Yucca Mountain decision, and yesterday, several said good riddance to him.

Reid had secured Jaczko a place on the five-member NRC commission and persuaded the White House to appoint the former science aide as chairman after President Obama was sworn in. Jaczko used the chairman's authority in 2010 to halt the agency's safety review of the Energy Department's application to complete the fuel repository. Obama, who had promised Reid during the 2008 presidential campaign that he would stop the project, directed DOE to shut it down.

Withholding information

Jackzo said his decision to end the NRC review simply acknowledged that the repository was dead. But an NRC inspector general's report last summer said Jaczko withheld information from other commissioners to influence their decision on ending the project.

NRC Inspector General Hubert Bell reported that "senior officials, managers and staff provided examples that they believed illustrated the chairman's failure to share with his fellow commissioners information needed to support their fully informed decision-making." They also reported instances of "unprofessional or manipulative" conduct -- charges Jaczko has also denied, the IG said.

The IG report quoted NRC operations director William Borchardt saying Jaczko told him he wanted to control the flow of policy issues to the commissioners "to enable them to more efficient and effective by not overloading them so they could focus on certain issues."

But Jaczko's exercise of the chairman's prerogatives in the case was the first wedge between him and the other commission members, a split that deepened beyond closure after the March 11, 2011, accident at the Fukushima Daiichi nuclear plant.

In addition to naming Jaczko chairman, Obama filled three NRC commission vacancies in 2010 by appointing Democrats William Magwood IV, a former DOE official, and Massachusetts Institute of Technology professor George Apostolakis and Republican William Ostendorff, a former GOP congressional staff member and Navy nuclear submarine commander.

The White House, which had thrown its support behind new nuclear power development as a key to reducing carbon emissions from the electric power sector, insisted to Reid that in return for putting Jaczko at the head of the agency, it would fill the Democratic seats with experts who were open to the nuclear option, according to sources close to the decision.

When Japan's nuclear crisis began, Jaczko used his chairman's authority to bar the other commissioners from the NRC crisis response center. While Jaczko has increased power by statute during emergencies, his relationship with his peers deteriorated further with his handling of the situation, they said.

This culminated in an extraordinary letter the four commissioners wrote last Oct. 13 to then-White House chief of staff Bill Daley, charging that he had "caused serious damage" to NRC and "undermined the ability of the Commission to function," "intimidated" and "bullied" senior staff and treated his fellow commissioners with "intemperance and disrespect."

Focus on safety and politics

In the House and Senate hearings that followed, Jaczko defended his conduct, saying that while he was intense in his advocacy and passionate about the need for safety regulation, he had not used anger as an intimidation weapon. The chairman wrote to Daley that the gulf between him and his colleagues was based on policy. "The Chairman is clearly the Commissioner most focused on nuclear safety, as a review of the public voting record demonstrates," he wrote.

After Fukushima, Jaczko pressed for the appointment of a special Near Term Task Force of agency veterans to seek out lessons for NRC and industry from accident. The task force recommendations have become the framework of the commission's response, but Jaczko quarreled with the other commissioners over how quickly recommendations should be enacted and by what routes the commission should act.

Jaczko wanted the most immediate safety changes in the Fukushima report imposed through commission orders, rather than a potentially far more time-consuming rulemaking process with its extensive solicitation of industry views. The four other commissioners -- Apostolakis, Magwood, Ostendorff and holdover Kristine Svinicki -- wanted input from senior staff, industry and interest groups before committing to action, and they got their way.

At a commission meeting last Oct. 11, Jaczko's frustration boiled over. "I have two issues that drive me nuts, and they're going to continue to drive me nuts until I'm no longer in the job," he protested. One concerned regulation of cooling water recirculation systems in emergencies and the other was the decades-long commission effort to strengthen nuclear plant fire protection regulation.

"If those service models are how we're going to do this, we're going to be working on this for the next 15 to 20 years," he said, speaking of the post-Fukushima regulatory changes.

The industry and its supporters are likely to be debating with critics and nuclear power opponents for years whether NRC's timetable is right or too slow.

From the agency's perspective, however, the split among the commissioners tore at a long-standing process for reaching decisions, a number of agency officials and retirees say. Jack Grobe, a former senior NRC staff member who served on the Fukushima task force, said in an interview after the arguments went public: "The interaction between our commissioners is embarrassing. It's not a matter of whether these are good people or bad people. It's the leadership framework that won't work anymore, and from my perspective, it's got to change.

"What makes nuclear power safe is the open and collaborative work environment. It's the set of values that our organization functions in. It is not a set of values that our commission is using," said Grobe, who retired from NRC and is now working in the industry.

A new chairman will have the chance to create a collaborative environment and a strong safety record. But the political polarization in Congress over the agency's role following the Yucca Mountain and Fukushima debates may delay confirmation of the new appointee and leave Jaczko in the post possibly for months to come.