The Virtual Bomb
News: The Nuclear Ignition Facility will allow the U.S. to keep testing nuclear weapons--and perhaps undermine treaties on global arms proliferation. it's promoted as a path to clean, boundless fusion energy. but a prominent science writer explains why this claim is dubious.
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A major new nuclear weapons project is being sold to the public as a potential source of boundless, clean, affordable commercial energy. In fact, its relevance to world energy needs is debatable, while its main goal--to help U.S. scientists maintain a huge nuclear arsenal after the Cold War--is all too clear.
The proposed National Ignition Facility would house a laser as big as a football field, located at Lawrence Livermore National Laboratory east of San Francisco. The laser would blast tiny pellets of nuclear fuel to trigger miniature thermonuclear explosions inside a sealed chamber. In this way, weapons researchers could simulate bomb blasts--"virtual" nuclear explosions, one might call them--in order to continue honing their nuclear skills after tests using real bombs are banned by international treaty. The superlaser would cost $1.1 billion ($1.8 billion if you include long-term operational costs) and is planned for construction starting in 1997, pending final approval from the Department of Energy.
If built, the National Ignition Facility would be the crown jewel of a post-Cold War nuclear weapons complex that is slated to include several other costly nuclear-simulation devices at the nation's main nuclear weapons labs: Lawrence Livermore in California and the Los Alamos and Sandia laboratories in New Mexico. The nuclear-simulation program (technically known as Science Based Stockpile Stewardship) "should enable the United States to. . .remain an acknowledged nuclear power without underground testing," according to an official summary of a 1994 Sandia conference on the project.
But critics warn that the laser and other planned nuclear-simulation devices could violate the spirit, if not the letter, of the Comprehensive Test Ban Treaty being negotiated in Geneva. It may also undermine efforts to renew the Nuclear Nonproliferation Treaty, which expires this spring and which some developing countries have refused to renegotiate until they see the U.S. making real progress toward a test ban.
Yet despite the risk to the treaties, weaponeers are forging ahead with plans to build the new superlaser. And to sweeten its appeal, they are emphasizing its potential for exploring a practically infinite source of nuclear energy: fusion. They point out that the same kind of fusion energy unleashed by a nuclear blast could, in principle, be released much more slowly--slowly enough to drive a turbine that powers an electrical grid. According to fusion proponents, the world could have enough fusion energy to last for millions of years because the oceans brim with a key nuclear fuel, deuterium. Also, they argue, fusion would emit less poisonous radioactive waste than its unpopular cousin, "fission," the process used to generate power in conventional nuclear plants.
Scientists have already spent four decades and billions of dollars trying to develop fusion energy--yet so far they have been unable to create a fusion reaction that will produce as much energy as it takes to initiate the reaction, or that will continue to burn on its own.
But even if scientists master these basics, serious problems with laser fusion underscore the remoteness of the National Ignition Facility's potential energy applications:
- Laser fusion, if successfully developed, would cost a fortune and involve large and numbingly complex, perhaps unreliable, machinery. A laser such as the one scheduled to be built at the National Ignition Facility would probably be useless for a full-scale fusion power plant because it gets too hot to fire more than a few times a day. (In contrast, the "driver" in an operating fusion plant would have to fire several times per second.) Even if that obstacle were surmounted, the cost of running a fusion plant would "probably be greater" than for fossil-fueled or nuclear-fission plants, according to a 1990 report by the Department of Energy's Fusion Policy Advisory Committee.
- Despite its "clean" reputation, fusion would require handling enormous quantities of radioactive material. Fusion plants need tritium, a radioactive gas that is easily absorbed by water and living organisms, and is extremely difficult to manage: It seeps through solid containers. Adding another twist, tritium currently can only be mass-produced in fission reactors--ironically, the same unpopular technology that fusion is intended to replace.
- A fusion reactor would also expel a Niagara of subatomic particles. These neutrons would render objects within and immediately outside the reactor (including the air itself) radioactive. As a result of neutron bombardment, the reactor vessel wall would become brittle and might have to be replaced every few years.
- Perhaps most serious, would-be nuclear proliferators might use commercial fusion reactors as a covert means to generate fissionable plutonium for nuclear weapons. Edward Teller, the "father" of the hydrogen bomb, once suggested developing fusion reactors for this very purpose.
The future of the Science Based Stockpile Stewardship program brightened with the Republican takeover of Congress. But even before the election, Energy Secretary Hazel O'Leary okayed $55 million for the National Ignition Facility's initial design and environmental analysis, though she won't decide whether to build it until early 1997.
In any case, other Science Based Stockpile Stewardship projects have already received preliminary funds from Congress. What kind of message does our "virtual" nuclear testing send the rest of the world? According to Greenpeace anti-nuclear campaigner Chris Zimmer, this one: "The U.S. just won't let go of the Bomb."
Science writer Keay Davidson won the 1994 National Association of Science Writers Award for an investigative series, "War Games," published by the San Francisco Examiner last spring, on the future of nuclear weapons labs.
