Is “nuclear waste” an outdated term? That’s what William Tucker, author of Terrestial Energy, argues in a recent Wall Street Journal
column titled "There Is No Such Thing As Nuclear
Waste." To hear him describe it, the nation's spent nuclear fuel—which will no longer find a permanent resting place at Yucca Mountain—is
actually pretty useful stuff. In addition to a lot of basically inert uranium-238, those spent fuel rods also contain radioactive isotopes that can be used for medical
and industrial purposes, as well as decent amounts of uranium-235 and plutonium, which can be reprocessed and used again as nuclear fuel. If
we can just keep reusing that nuclear fuel, Tucker argues, maybe there’s no need for a Yucca-style waste repository, after all.
Unfortunately, there are two big reasons that reprocessing is unlikely
to solve the problem of nuclear waste. The first is that it’s not
cost-effective, and won’t be for a long time yet. Reprocessing is an
expensive undertaking, and mining new uranium for nuclear fuel is—relatively speaking—quite
cheap. Harvard nuclear-policy researcher Matthew Bunn calculates that the
price of uranium would have to go higher than $360 per kilogram before
reprocessing becomes cost-competitive. The current price of uranium is about $100 per kilogram—far below the level at which reprocessing could compete. What's more,
Bunn thinks that this price has been significantly inflated by short-term production bottlenecks and is likely to drop in the future.
Of course, if running reactors on reprocessed fuel helped reduce the overall amount of nuclear waste—and therefore the need to build expensive waste repositories —there
might be a case for doing so even if it costs more than running them on
newly-mined uranium. But if anything, reprocessing actually increases the demands on nuclear-waste
repositories. That’s because the most important consideration when
designing a long-term waste repository is not the volume of radioactive
waste but the amount of heat it gives off. And according to Alison
MacFarlane, George Mason University professor of nuclear policy, spent
mixed-oxide fuel—which is what’s left over after running a reactor on reprocessed nuclear waste—is about three times as hot as regular spent fuel rods.
It’s possible that, one day, more advanced reactors—fast breeder reactors, say—will
be able to cost-effectively make use of spent nuclear fuel to produce
electricity. Unfortunately, that day is a long ways off. Until then,
nuclear waste will remain nuclear waste.