The nuclear waste problem: Where to put it?
Currently, the US has no permanent disposal site for nuclear waste. A new presidential commission is exploring ways to solve the problem of storing highly radioactive spent nuclear fuel.
(Page 2 of 2)
What technologies might the commission evaluate?Skip to next paragraph
Subscribe Today to the Monitor
1. Reprocessing spent uranium reactor fuel.
Some argue that reprocessing would reduce waste by separating out plutonium that could then be packaged as "mixed oxide," or MOX, fuel and used in reactors in place of low-enriched uranium. It's not clear whether the amount of high-level waste would be reduced much, unless some other technology is used in conjunction with it. France uses reprocessed MOX fuel to power its nuclear plants, but MOX remains a proliferation threat because the plutonium in it could be used in a nuclear bomb. Reprocessing also requires having a lot of plutonium. In 2008, France reported a stockpile of 55 metric tons of separated plutonium from commercial reactors, enough for roughly 6,000 bombs, according to Frank von Hippel, a nuclear physicist and nonproliferation expert at Princeton University in New Jersey. The technology is also costly: A reprocessing plant might cost $40 billion or more.
Reprocessing, combined with a fleet of fast reactors (see No. 2 below), could in theory burn up long-lived radioactive elements that make spent fuel difficult to site and costly to store. But nonproliferation experts are doubtful. "No potential reprocessing option that would reduce the proliferation risk has yet been identified," says Edwin Lyman, a physicist and proliferation expert with the Union of Concerned Scientists in Washington.
2. Fast neutron reactors.
Advantages include their ability to use up, or "burn," plutonium and other undesirable, long-lived radioactive elements, potentially reducing the space needed for longer-term storage. Disadvantages include high cost, complexity, extended shutdowns, and use of plutonium-based fuel that's vulnerable to theft and proliferation. A few fast reactors were built and tested in the US, but the technology was not pursued because of cost, reliability concerns, and proliferation issues.
3. Traveling wave reactors.
A TWR "initially contains only a small igniter of fissile fuel, which is used to kick off the chain reaction," explains a publication from TerraPower, which is working to develop TWRs. "The wave of fission would move slowly through the core, splitting many more of the fuel atoms than a conventional reactor." In theory, it could use spent fuel from conventional reactors, or draw on stocks of depleted uranium. This would reduce the volume of spent fuel and waste, thereby also reducing the risk of proliferation.
4. Deep geological disposal.
Searching for a site to replace Yucca Mountain is not the commission's job, but the group is asked to propose a process for selecting one.
When will the commission make its recommendations?
The first recommendations of the panel – co-chaired by former Indiana Congressman Lee Hamilton and Brent Scowcroft, a former national security adviser – are due in 18 months, with the final report set for release in 2012.