Pyroprocessing: A Hot-Button Issue

Pyroprocessing (n.): a method to recycle spent nuclear fuel through electrorefining.

Nuclear power is sort of like a bottle of cheap vodka—it’s fun to consume, but, oh, the headaches. One of the biggest head splitters is the question of what we should do with nuclear waste.

Take South Korea, for example. Without significant stores of fossil fuels, it has been relying on nuclear power for decades. The Asian tech giant is the world’s fifth-largest producer of nuclear energy, which now accounts for 26 percent of the country’s electricity generation. (Before the 2011 Fukushima disaster in Japan, the South Korean government had planned to expand production.)

But with all that energy came 10,000 tons of spent nuclear rods that are currently sitting in temporary storage pools with no permanent place to go. The country's government is calling it a national crisis.

Few Americans think of spent nuclear fuel as a national crisis, but we’re in the same (radioactive) boat as South Korea. Nuclear plants generate 19 percent of our electricity. On-site at our country’s 60-plus nuclear power plants currently sit 80,000 tons of spent nuclear fuel, cooling off (very slowly) in steel-lined concrete pools and large steel-and-conrete canisters. Those containers can do the job for a few decades, but we need a long-term plan. Right now, the plan is to continue arguing about Nevada’s Yucca Mountain. The Obama administration shut down the facility four years ago and assembled a Blue Ribbon Commission to look into the issue of long-term—long, as in hundreds of thousands of years—storage. House Republicans are now trying to revive the Yucca project, which hints to just how well the search for alternatives is going.

When a waste stream gets too big to handle, recycling becomes an attractive alternative. The partial recycling of spent nuclear fuel has a fancy name: reprocessing. In traditional nuclear reprocessing, you separate uranium and plutonium from the other materials within the fuel rods that can no longer support efficient fission and drive a power plant. The plutonium can, in theory, be sent back into a specialized nuclear power plant for reuse. Many of the other materials can then be classified as “low-level” waste, which is less dangerous to handle and store than an intact spent fuel rod would be.

Traditional nuclear reprocessing, however, has a major drawback: It takes just 20 pounds of the recycled plutonium to build a nuclear bomb. For this reason, President Jimmy Carter banned commercial nuclear reprocessing in 1977, and the United States hasn’t gone back. The United Kingdom, France, Russia, Japan, and India, though, all continue to reprocess spent nuclear fuel. (Note: NRDC, which publishes Earthwire, opposes all forms of nuclear reprocessing. For an explanation of that policy, click here.)

Is there a way to reprocess spent fuel rods without expanding the world’s supply of nuclear bomb fuel? That’s the idea behind pyroprocessing. Rather than separating the plutonium completely, pyroprocessing attempts to combine it with other waste products from the nuclear fuel rod, such as neptunium, americium, or curium (those high-number elements you didn’t talk about in high-school chemistry). Theoretically, you could still reuse that mixed plutonium to generate nuclear power, but it wouldn’t be pure enough to build a useful weapon.

Since we’re not currently pyroprocessing spent nuclear fuel on any notable scale, you might have guessed that there’s a problem with it. In fact, there are a few. First, opponents worry that it’s too easy to adjust a pyroprocessing system to make weapons-grade plutonium. This is a major concern in Asia. China is already uncomfortable with Japan’s nearly 50-ton stockpile of plutonium. It would become even more uneasy if South Korea began producing large amounts of it. In 2013, two-thirds of South Koreans expressed their support for a nuclear arsenal to deter North Korea, so pyroprocessing could prove very tempting. U.S. laboratories are also working with South Korea on pyroprocessing technology, which further complicates the geopolitical implications.

Additionally, pyroprocessing would only reduce the long-term storage issue—not solve it completely. After several rounds of recycling, there would still be high-level nuclear waste that needs a place to live for the next few hundred millennia. Also, reprocessing increases the volume of low-level nuclear waste—the stuff that will need a safe place to stay for several years before it can be disposed of in a landfill.

Whether pyroprocessing has the potential be a commercially viable energy source is another matter. Only breeder and MOX reactors can use the recycled plutonium. The former are very expensive, and the latter might lead to more catastrophic nuclear accidents. (One of the reactors in the Fukushima disaster was burning MOX fuel.)

Despite South Korea’s enthusiasm, pyroprocessing remains an obscure method for dealing with spent nuclear fuel worldwide. Without any other good storage options, though, the door will continue to be open to complicated, partial solutions like this one. In other words, this hangover is likely to continue for a few more decades at least.