South Korea is looking toward a low-carbon future that likely includes boosting nuclear power consumption. The buildup of nuclear waste in the South creates a problem, however, and Seoul and Washington must reconsider an old agreement to deal with it.
South Korea's use of nuclear energy is a sensitive subject. Because of environmental and security concerns, promotional videos like this one are about the closest look journalists ever get of its 20 nuclear power reactors.
Those reactors provide about 40 percent of the electricity for an energy-hungry country.
Leaders here think expanding nuclear power is one way to grow the economy and reduce carbon emissions.
But spent fuel from nuclear plants is piling up - 10,000 tons already - with 700 tons added every year, which must be safely stored.
Lawmaker Choi Gu-sik says that is a problem.
"The Korean peninsula will be filled to capacity with nuclear waste by 2016," said Choi Gu-sik. "Unless we start to reprocess, Korea will be full of nuclear waste."
But South Korea can not reprocess spent fuel to reuse it, because of a 1974 agreement with the United States to prevent a nuclear arms race on the peninsula.
That deal expires in 2014, and South Korean officials want to update it. The U.S. so far shows little interest.
Technology may ease some U.S. concerns. Lee Gun-jae is a nuclear physics professor at the Korea Advanced Institute for Science and Technology. He says it is important to distinguish between reprocessing fuel, which can be used to make weapons, and recycling it.
"Reprocessing is what France, the United Kingdom and Japan do," said Lee Gun-jae. "You can also call it 'wet processing.' It is a well defined technology that the military can use to produce plutonium. Korea has no interest in that kind of technology. What we're interested in is pyro processing."
Advocates say pyro processing extracts material that can be reused for electricity, but not for weapons, and reduces the volume of spent fuel by up to 90 percent.
But Dan Pinkston, northeast Asia analyst for the International Crisis Group, says the remaining 10 percent carries a risk.
"Critics argue that it gets you closer - so you have a more concentrated batch of waste, and that could be susceptible to theft or sabotage and terrorist attacks, something like that," said Dan Pinkston. "So there are still some concerns about it."
What concerns some diplomats is that any change in the South Korean nuclear status quo may complicate talks on ending North Korea's nuclear weapons programs.