The US Department of Energy predicts that we'll spend $150 billion to dispose of radioactive leftovers generated during four decades of Cold War weapons production. Paul Brown, a physics PhD from Boise, Idaho, says he can do it for less than a quarter of that price - without burying hazardous waste. How? Give the nukes a taste of their own medicine: Blast them with radiation.
If this sounds simple, it is. Beam an element with a stream of alpha particles and it turns into another element. This happens routinely in laboratory "atom smashers," where, for example, beryllium is commonly converted into carbon, with heat as a by-product.
Brown showed that when nuclear waste is showered with gamma rays, it's transformed into compounds that become safe within a few months, rather than thousands of years. "It's textbook radiochemistry," he says. But after searching the annals of atomic literature, he couldn't find anyone who had proposed the idea.
Bob Park of the American Institute of Physics, who routinely debunks fringe science, says Brown's scheme is not far-fetched. John Schiffer, senior scientist and an experimental nuclear physicist at Argonne National Laboratories, confirms that gamma radiation "could convert long-lived radioactive isotopes into shorter-lived ones."
The approach is not without its challenges, however. Schiffer complains that gamma rays would result in an enormous amount of excess heat. Adds Gary Doolen, a physicist at Los Alamos National Laboratories, "It's also very expensive to generate high-energy gamma rays."
But Brown has thought about all this already. He says the excess heat could generate electricity - more than enough to run the whole operation. The inventor adds that a typical neutron-beam research project costs $1.3 billion, while he hopes to build an entire plant for just $5 million.
With a patent for his idea pending, Brown formed Nuclear Solutions, a company that will soon run tests at the University of Illinois or MIT. And, since the Department of Energy already has spent $2.5 billion on "innovative waste-cleanup technologies," he's negotiating with the agency to give him his meager millions to build a pilot plant.
"Some waste products have half-lives of 24,000 years," says Brown. "There's no such thing as a steel drum you can bury that will remain safe for that length of time." Processing nuclear waste with gamma rays would be a miracle tool for regulatory agencies doing radioactive cleanup.
Brown's ultimate vision is of nuclear-power stations that neutralize their waste as soon as it's created. "I'm not an antinuke activist," he says. "I'm a realist. Obviously, we need a method to remediate nuclear waste - and ours really works."
- Charles Platt