Nuclear Regulatory Commission chairman Gregory Jaczko has announced his resignation. Jaczko, a former staffer for Senate Majority Leader Harry Reid, was widely credited with — or blamed for — the NRC's acquiescence in abandoning the federal commitment to build a nuclear waste repository at Yucca Mountain, in Reid's home state of Nevada.

The troubled Hanford vitrification plant is designed to encase high-level waste in glass logs that meet the specs for the Yucca Mountain repository. And if Yucca — or some other designated site — isn't ready to receive it, all that waste may stay at Hanford indefinitely.

With Jaczko gone, what are the chances that Yucca will be revived? What are the chances that anything will change?

President Barack Obama has nominated Allison Macfarlane, an associate professor of Environmental Science and Policy at George Mason University, to succeed Jaczko. Macfarlane has been called "a vocal critic of the proposed Yucca Mountain nuclear waste repository."

Whoever chairs the NRC, most people think that reviving Yucca looks like a long shot. In fact, more people have already moved on.

For those who came in late, a little background: Founded during World War II as history's first plutonium factory, Hanford kept cranking out plutonium until 1989. By that time the federal government had accumulated some 53 million gallons of highly radioactive waste in steel tanks, some of them single-walled models of World War II vintage that had way outlasted their life expectancies. Some had already leaked. At that point, the U.S. Department of Energy, the U.S. Environmental Protection Agency, and the state Department of Ecology signed a Tri Party Agreement under which the Energy Department would meet various conditions for cleaning up the site.

Under that agreement and a Hanford consent decree signed in 2010, the federal government is building the world's largest vitrification plant, designed to encase the most highly radioactive waste in borosilicate glass. The plant is supposed to be up and running by 2019. The last of the old single-walled tanks is supposed to be emptied by 2040. All the waste is supposed to be treated by 2047.

But ... The vit plant has been designed to produce those glass logs for long-term storage at the Yucca Mountain waste repository. If the federal government decides on some other repository, the logs may or may not meet its specs. If the government doesn't create a repository, that waste may stay at Hanford forever.

People assume that vitrification is merely a step toward getting the waste out of Washington. But the Tri Party Agreement doesn't specify that. The feds have never promised to ship the waste anywhere else.

The vit plant, of course, has problems of its own. Energy Secretary Steven Chu visited Hanford this month to assure people that the feds care about workplace safety. The Defense Nuclear Facilities Safety Board has identified five unresolved saftey issues at the vitrification plant — including a question about whether or not the radioactive sludge will stay well mixed in the big tanks — for which the design is largely complete. Earlier this year, the board had suggested that materials in the plant's "black cells" — each of which will contain 3,900 linear feet of piping and all of which will become too radioactive for inspection or repair — might not last the full 40 years that will be required to incorporate all of Hanford's high-level liquid waste into glass logs. The Department of Energy Inspector General's draft vitrification plant audit, released on Jan. 13, makes it clear that Bechtel hasn't inspected the welds well enough to know the chances that one or more will fail. In addition, three whistleblowers allege their jobs have been lost or jeopardized because they have called attention to Hanford safety concerns. The safety board was told at a hearing on May 22 that Hanford has been making progress on safety; not everyone buys that reassurance.

While construction has continued on the vitrification plant, all work on Yucca Mountain has ground to a halt. In 1980, the federal government decided on deep geological disposal of waste from Hanford and the nation's civilian nuclear plants. Later in the decade, it started culling possible sites in 36 states. In 1986, the feds chose Nevada. Nuclear Waste Policy Act amendments of 1987 called for studying and licensing a site at Yucca Mountain. In 2002, the secretary of Energy finally recommended Yucca Mountain. President George W. Bush accepted the recommendation, Nevada's governor vetoed the choice, and Congress overrode his veto.

Of course, people in Nevada didn't want the repository. Campaigning there in Harry Reid's home state, then-Sen. Barack Obama said that if he were elected president, he'd kill the Yucca project. Since the election, his administration has tried to make good on that campaign promise.

First, in January 2010, his Department of Energy tried to withdraw the license application for the Yucca Mountain facility with prejudice — which means it couldn't be re-submitted at a later date. The state of Washington intervened before the NRC’s Atomic Safety and Licensing Board, which denied the DOE's motion to withdraw. The dismantling of Yucca continued, though. The DOE appealed to the NRC. The Obama administration’s FY2011 budget proposal eliminated all funding for the Yucca Mountain project.

In early 2011, Obama and Energy Secretary Chu had established a Blue Ribbon Commission — Allison Macfarlane was a member — to consider alternatives to Yucca Mountain. Last September, the NRC — chaired, of course, by Jaczko — announced that it had deadlocked 2-2 on the issue of withdrawal — but ordered the Atomic Safety and Licensing Board to close out all the issues before it by the end of the month.

This January, the Blue Ribbon Commission recommended Plan B, a "broad consent" approach. The Secretary of Energy had made clear to the commission members that Yucca Mountain was not supposed to be on the table. Basically, the commission recommended dumping the nation's nuclear waste some place where people will welcome it. Right. The commission didn't suggest with a timetable, a budget, or even a process.

Washington and South Carolina had sued in the D.C. Circuit Court to keep the DOE from terminating the Yucca site. Last year, the court found that the issue was premature, because the NRC hadn't issued a decision on the merits of the application to build the Yucca Mountain repository or one reviewing the Atomic Safety and Licensing Board’s order denying the Department of Energy’s motion to withdraw that application. Washington and its co-plaintiffs then asked for a writ of mandamus forcing the NRC to decide, and to consider the DOE's application on its merits. On May 2, Washington state Attorney General Office's Senior Counsel Andy Fitz appeared before the U.S. Court of Appeals of to argue the mandamus case.

So the issue is still alive in the courts. Nevertheless, our two gubenatorial candidates, Rob McKenna and Jay Inslee, are among the very few people who still think there's any chance of reviving the Yucca Mountain project. As attorney general, McKenna has been doggedly fighting the decision to scrap Yucca in court. He has won praise from The Seattle Times for continuing to fight in the face of the D.C. court's decision. As a member of Congress, Inslee led efforts to fight the reversal legislatively. Asked if he thinks there's any chance at all that the Yucca will be built, Inslee says yes.