Wednesday, October 30, 2013

Where Should We Store Nuclear Waste?

By: By Laura Dattaro
Published: October 30,2013
 
 
 
 
 

The Three Mile Island nuclear power plant in Middletown, Pennsylvania. (Jeff Fusco/Getty Images)
In 35 states across the U.S., small fuel rods once used to produce nuclear power sit in storage facilities, mostly at nuclear power plants. The facilities are temporary — the United States has no permanent disposal spots for this kind of waste, according to the United States Nuclear Regulatory Commission. And despite decades of work, we’re nowhere close to a real solution.
That’s not to say there aren’t plenty of ideas. Most bury the waste deep underground, in large repositories of rock or in drilled columns. But each has its issues. Not all rocks are created equally, for example; some have characteristics better suited to containing the dangerous radioactive waste than others.
Christopher Neuzil, a United States Geological Survey geologist, prefers shale. When looking for a good place to bury waste, one important factor is the rock’s permeability — “the ease with which fluid can flow through the rock,” Neuzil told weather.com. “One of the things you worry about with a repository is whether you’re going to have groundwater flowing through the repository, picking up contaminants and delivering them to places you don’t want them to go.”
A clay-rich sedimentary rock found in great abundance, shale has very low permeability, making it a popular option and one Switzerland, France and Belgium are currently considering. Granite is another possibility, but tends to fracture and experience faults, Neuzil said. Neuzil discussed both options at this week’s Geological Society of America (GSA) meeting in Denver.
“Deep boreholes” — drilling columns more than 16,000 feet deep into the Earth to hold the contained waste and then sealing them off for good — could also work. But they carry their own issues, according to Bret Leslie, senior staff with the U.S. Nuclear Waste Technical Review Board (NWTRB), who discussed the boreholes at the GSA meeting.
The technology and expertise for drilling the holes is about 30 to 40 years behind that of geologic disposal, Leslie told weather.com, and while they are feasible, research into using the holes shouldn’t impede exploring the possibilities of repositories.
In a July letter to the Department of Energy, Rodney Ewing, chair of NWTRB, outlined the difficulties facing deep boreholes, including attempting to characterize the rock found at such depths and the large number of boreholes necessary, in addition to the new technologies needed. “Because of these technological challenges and the significant scale of a deep borehole disposal program,” the letter states, “the Board reiterates its long-standing support of mined geologic disposal.”
The problem of disposing of our waste is not just a scientific one. In fact, Neuzil said, the technical issues aren’t necessarily that difficult. What’s preventing a plan from moving forward has far more to do with politics than science, including very high safety thresholds for repositories, he added. “They’re unrealistically stringent, in my view.”
This is a decades-old battle. In 1982, Congress passed the Nuclear Waste Policy Act. A 1987 amendment directed the DOE to bury the waste at Yucca Mountain, 100 miles north of Las Vegas, a process set to have started in 1998. But political pressures caused defunding of the so-called Yucca Mountain Project in 2010, leaving a law on the books requiring waste burial at Yucca but not enough funds to make it happen.
A solution isn’t likely to come within the next decade, Neuzil said, and could take closer to 30 or 40 years. “As antsy as people may feel about wherever this gets buried, the reality is the stuff is sitting on site in any number of places and usually in places you might think of as vulnerable,” he said. “It really is [in] everybody’s best interest that this be done as expeditiously as possible. Which is probably not going to happen anytime soon.”

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