By Allison Macfarlane, Sharon Squassoni
Now that Americans are “woke” about waste in general, they may turn to the specific kind produced by the nuclear energy industry. Plans to revitalize US nuclear power, which is in dire economic straits, depend on the potential for new, “advanced” reactors to reduce and recycle the waste they produce. Unfortunately, as they “burn” some kinds of nuclear wastes, these plants will create other kinds that also require disposal. At the same time, these “advanced” reactors—many of which are actually reprises of past efforts—increase security and nuclear weapons proliferation risks and ultimately do nothing to break down the political and societal resistance to finding real solutions to nuclear waste disposal.
The current nuclear dream is really no different from previous ones of the last 70 years: the next generation of reactors, nuclear power advocates insist, will be safer, cheaper, more reliable, less prone to produce nuclear bomb-making material, and more versatile (producing electricity, heat, and perhaps hydrogen), without creating the wastes that have proved almost impossible to deal with in the United States. The Nuclear Energy Innovation and Modernization Act specifically describes the advanced reactors it seeks to support as having all those positive characteristics. This newest burst of enthusiasm for advanced reactors is, however, largely fueled by the idea that they will burn some of their long-lived radioisotopes, thereby becoming nuclear incinerators for some of their own waste.
Many of these “advanced” reactors are actually repackaged designs from 70 years ago. If the United States, France, the UK, Germany, Japan, Russia, and others could not make these reactors economically viable power producers in that time, despite spending more than $60 billion, what is different now? Moreover, all of the “advanced” designs under discussion now are simply “PowerPoint” reactors: They have not been built at scale, and, as a result, we don’t really know all the waste streams that they will produce.
It’s tempting to believe that having new nuclear power plants that serve, to some degree, as nuclear garbage disposals means there is no need for a nuclear garbage dump, but this isn’t really the case. Even in an optimistic assessment, these new plants will still produce significant amounts of high-level, long-lived waste. What’s more, new fuel forms used in some of these advanced reactors could pose waste disposal challenges not seen to date.
Some of these new reactors would use molten salt-based fuels that, when exposed to water, form highly corrosive hydrofluoric acid. Therefore, reprocessing (or some form of “conditioning”) the waste will likely be required for safety reasons before disposal. Sodium-cooled fast reactors—a “new” technology proposed to be used in some advanced reactors, including the Bill Gates-funded TerraPower reactors—face their own disposal challenges. These include dealing with the metallic uranium fuel which is pyrophoric (that is, prone to spontaneous combustion) and would need to be reprocessed into a safer form for disposal.
Unconventional reactors may reduce the level of some nuclear isotopes in the spent fuel they produce, but that won’t change what really drives requirements for our future nuclear waste repository: the heat production of spent fuel and amount of long-lived radionuclides in the waste. To put it another way, the new reactors will still need a waste repository, and it will likely need to be just as large as a repository for the waste produced by the current crop of conventional reactors.
Recycling and minimizing—even eliminating—the waste streams that many industries produce is responsible and prudent behavior. But in the context of nuclear energy, recycling is expensive, dirty, and ultimately dangerous. Reprocessing spent nuclear fuel—which some advanced reactor designs require for safety reasons—actually produces fissile material that could be used to power nuclear weapons. This is precisely why the United States has avoided the reprocessing of spent nuclear fuel for the last four decades, despite having the world’s largest number of commercial nuclear power plants.