The National Ignition Facility: Buyer Beware
In September 1996, when President Clinton signed the “zero-yield” comprehensive test ban-a treaty outlawing all nuclear explosions-he managed to win over the treaty’s strongest opponents. But this support did not come for free. The Pentagon, the Joint Chiefs of Staff, and the weapons labs conditioned their approval of a test ban on a number of “safeguards.” As part of the agreement, Clinton declared that if ever a high level of confidence in a certain type of nuclear weapon could no longer be certified, he would be prepared to invoke the supreme national interest clause under the test ban and conduct whatever nuclear testing may be required. “Exercising this right, however, is a decision I believe I or any future president will not have to make,” Clinton’s official statement read. His optimism may have been connected with another condition imposed by the military and the labs: full funding for the Department of Energy’s Stockpile Stewardship and Management Program “over the next decade and beyond.” The program is slated to receive about $40 billion over the next 10 years.
The stewardship program is supposed to help maintain the safety, reliability, and performance of the nuclear arsenal so that no U.S. president has to resume nuclear testing. It would achieve this goal by keeping three separate nuclear weapons laboratories in operation-Los Alamos and Sandia in New Mexico, and Lawrence Livermore in California-and by spending $3 billion to build a variety of new experimental facilities to simulate different aspects of a nuclear explosion. Some facilities would address the primary stage of a warhead and some the secondary stage (in thermonuclear weapons, a primary, or fission, stage produces x-rays to implode the secondary, which releases energy through fusion); other facilities would simulate the effects of nuclear explosions on military hardware. About a third of this funding would be spent on new supercomputers to make the most use of the new facilities and to tie the three labs together into one “superlab.”
The flagship of this armada of new facilities is the National Ignition Facility, or NIF, a $1.1 billion laser fusion laboratory slated for construction by 2002 at Livermore. The project has already received more than $250 million, and its total cost over 30 years would be $4.5 billion, not accounting for inflation. The decision to start construction will be made in mid-1997.
The trouble is, the Department of Energy has yet to offer a convincing rationale for why this most expensive of stewardship facilities should be built. For example, one of NIF’s main purposes, according to DOE, is to help assess age-related changes in warhead secondaries and determine their impact on the reliability of the weapons. But secondary components of nuclear warheads have never worn out, and the ones we have today could probably last for decades; there is no rush to build NIF. Moreover, problems with secondaries would have a relatively minor impact on overall warhead performance. And when defects do appear, NIF may not play much of a role in fixing them.
The Energy Department foresees other, subsidiary missions for NIF. One is to maintain a cadre of scientists to assess future problems with the arsenal or design new weapons if the Cold War heats up again. Another mission is to allow civilian research on fusion energy and other areas of basic and applied science. But each of these justifications for NIF is fraught with risky or unwarranted assumptions.
Few question the need for a stewardship program to monitor the nuclear arsenal as it ages, and to deal with any problems that might crop up. The issue is what kind of a stewardship program the nation needs, and what new facilities-if any-are required to do the job. NIF is the most glaring example of a stewardship facility that is not essential to the mission of preserving the nation’s nuclear arsenal.
The most direct link between NIF and stewardship is the laser facility’s presumed role in assessing problems that might arise in aging secondaries. The hope is that the facility will be able to reproduce the conditions found in an exploding thermonuclear weapon, but on a much smaller scale.
NIF is an “inertial confinement fusion” facility. It would use the largest and most powerful laser in the world, made up of 192 separate beams, to deliver a laser pulse of 1.8 megajoules of energy (far more than the 40 kilojoules now available on Livermore’s NOVA laser). This energy would be used to implode deuterium-tritium pellets to produce billionth-of-a-second bursts of fusion energy for study. By improving our knowledge of weapons physics, the argument goes, NIF will help scientists gauge the seriousness of defects that might occur as the stockpile grows older.
The aging of the stockpile is related to the end of nuclear testing. Over the last 40 years, the United States continually upgraded and replaced older warheads by developing new designs with the help of nuclear tests. Without such tests, the Pentagon does not currently plan to replace existing warhead types with new ones in the future. According to Harold Smith, assistant to the secretary of defense for nuclear, chemical, and biological weapons, quoted in the May 9, 1996, issue of Inside the Pentagon: “There are no new [designs for] warheads. There cannot be. Because if you cannot test, you cannot develop new warheads. That is almost the eleventh commandment as given to Moses on Mount Sinai.”
As long as this sentiment is so strongly held in the Pentagon, the average age of the stockpile will grow steadily from 13 years today to 20 years by 2005, taking into account the retirement of some of the older weapons. (If the United States and Russia agree to further cuts in their arsenals, this average would fall, since older weapons would likely be eliminated first.) Although 20 years is often characterized as the maximum life of a weapon, it is actually the shortest lifespan contemplated. The Department of Energy’s stockpile management program-which is responsible for manufacturing new warhead parts as the stewardship program deems necessary- states in its February 1996 “Draft Analysis of Stockpile Management Alternatives” that nuclear components “are expected to have service lives significantly in excess of their minimum design life of 20 to 25 years.” According to the report, “Experience indicates that weapons can remain in the stockpile well beyond their minimum design lifetime.”
Since 1958, an Energy Department effort known as the Stockpile Evaluation Program (SEP) has compiled a detailed record of the condition of nuclear weapons.
Significantly, SEP has yet to turn up any evidence that age-related defects appear with greater frequency over time. Nor is there any sign that warhead secondaries, the components most relevant to NIF, are prone to age-related defects at all. If anything, secondaries appear to be the least vulnerable nuclear components of the weapon.
Under SEP, 11 sample warheads of each weapon type are taken out of the stockpile every year, according to “Stockpile Surveillance: Past and Future,” a September 1995 report by the three weapons labs. The samples are dis-assembled and inspected, and the non-nuclear components are subjected to laboratory and flight tests. As a rule, the nuclear explosive package from one sample per year per weapon type is destructively examined (for example, the plutonium components are cut up for metallurgical analysis) by whichever weapons lab produced the warhead. This sample is then retired from the stockpile and must be replaced with components that are either held in reserve or, if spares are not available, newly produced. The other 10 samples per warhead type are returned to the stockpile with original nuclear components and replacement non-nuclear parts as needed. This process begins and ends at the Pantex plant near Ama-rillo, Texas.
Of the 70,000 or so U.S. nuclear weapons produced since 1958, the Stockpile Evaluation Program has examined more than 13,800 weapons of 45 different types. About 800 distinct sorts of findings have warranted further investigation. Of these, about 400 were deemed “actionable,” meaning that the finding resulted in corrective measures (to the weapon itself or to the production process) or in a downgrading of the weapon’s assumed reliability or yield. Most such findings have occurred in the first few years of a weapon’s life as a result of problems in design, fabrication, or production-problems that tend to get worked out early on. As the weapons age, fewer actionable findings appear. Using past experience to project the future health of the stockpile, the weapons labs estimate in their joint report that over the next 10 years there will be an average of one to two actionable findings per year, one of which will result in a change to a warhead.
These numbers, however, do not distinguish between production problems and age-related defects, such as cracks, corrosion, and the like. Production problems are unlikely to reappear, and aging problems serious enough to correct have been restricted almost entirely to non-nuclear components, such as detonators, cables, and neutron generators. If found to be defective, all these parts can be newly fabricated and fully tested.
The challenge today for the laboratories is to assess the nuclear parts (primary “pits” and secondaries) of the warhead that can no longer be tested in actual detonations. So far, the nuclear heart of the primary-the pit, made of plutonium, uranium, and beryllium-has received a clean bill of health. While acknowledging that few data are available for pits older than 25 years, the stockpile management program states in its February 1996 draft analysis that “no age related problem has been observed in pits up to 30 years in age.” Which is not to suggest these components are immortal; at some point, the plutonium’s radioactive decay could lead to performance problems. According to a senior scientist in the Energy Department’s stockpile management program, pits may last “40, 60, 100 years, but not 1,000.”
But what about secondaries, the supposed deterioration of which serves as the raison d’tre for NIF? Here the record is similarly encouraging. Secondaries consist of uranium, lithium deuteride, and other subcomponents isolated from the external environment in a sealed can. Although the materials can still react with each other, this has not been a significant problem, according to DOE documents obtained by the Institute for Energy and Environmental Research in Tacoma Park, Md. Examinations of secondaries since 1958 have uncovered only two types of age-related defect, neither of them serious enough to correct. In fact, the stockpile management program acknowledges that “there has been no degradation or concern for performance for any of the weapons in the stockpile of 2004 and beyond.”
Even if aging problems with secondaries appear, these warhead stages have the advantage of simplicity and reliability. Says the DOE senior scientist, “Once the primary [detonates], the secondary will also, even if it has some defects.” Unlike the primary stage, which drives the nuclear explosion, the performance of the secondary appears to be relatively insensitive to age-related changes.
If the historical record is any indication of future performance, aging of nuclear components seems likely to remain a rare problem for the foreseeable future. With an average stockpile age of 13 years (the oldest deployed warheads are now 18 years old), and the knowledge that nuclear components can last well beyond the design life of the overall warhead, we are possibly decades away from encountering any significant age-related problems with nuclear components. Hence there is no rush to build new facilities to address aging problems, especially with secondaries.
When and if serious defects are found in secondaries, NIF’s contribution to fixing them would probably be minimal. According to the “Programmatic Environmental Impact Statement” published by DOE in September 1996: “If an unanticipated change relevant to the high-energy-density phase of weapon operation is observed in the weapon surveillance program [SEP], specially designed NIF experiments could aid weapons scientists in validating aspects of their integrated computer models to assess whether that change would adversely impact the weapon’s reliability.”
The trouble with this justification is that it is not clear how helpful NIF would be in assessing age-related changes. Moreover, such assessments are not even necessary. A simpler approach is merely to build a new part. If the labs are unsure how significant a defect is, the management program can have a replacement part manufactured at the Oak Ridge plant in Tennessee, which will maintain its capacity to build secondary components. According to the Pentagon’s Smith, “The way you take care of aging is, in extremis, you build a new one. And that’s what we’ll do.” Alternatively, the part could be replaced by a spare in reserve.
Proponents also suggest that experimental results from NIF could be used to improve computer codes to determine whether rebuilt parts would behave as expected. But that is not a great concern for secondaries. According to a Los Alamos scientist, “secondaries are much more forgiving than primaries.” And incorporating NIF data into these codes would entail some risk. Computer codes for designing and simulating nuclear weapons have been “normalized” to nuclear test results-that is, the codes are based on data from actual explosions. Modifying the codes on the basis of NIF experiments could distance them from past test experience, possibly rendering them less reliable.
If NIF is not needed to fix warhead problems, then why do we need it at all? According to DOE, the broader NIF stewardship mission is to act as a “magnet” to draw fresh talent to Livermore and keep current weapons designers engaged, making it easier to assess warhead problems and design new warheads if international relations go sour. As Victor Reis, assistant secretary of energy for defense programs and architect of the stewardship program, testified before Congress in 1994: “The whole idea of lasers is for understanding the physics of secondaries, but also more particularly, for maintaining that cadre of scientists who both understand the fusion process and all the things that go along with that… . The stewards really are more important than the equipment.”
But while NIF may succeed in attracting new talent to work on nuclear physics, it is not clear that it would attract people who want to do weapons work. Supercomputer experience is more relevant to the career of a budding weapons designer than a job pushing the envelope of fusion research. So it seems likely that the $93 million IBM supercomputer Livermore is due to receive in 1998-a machine that will run 300 times faster than any existing computer-will play more of a “magnet” role than NIF. If we are genuinely concerned about maintaining expertise in weapons physics, $4.5 billion in salary increases for weapons designers might be money better spent.
But perhaps the concern itself is misguided. If more nuclear weapons were needed in a renewed Cold War, the United States could build them using existing designs, a job that would not require advances in nuclear weapons physics. In the worst and most unlikely case-new types of warheads are needed to counter an adversary’s qualitative leap-design teams could be reconstituted at the labs, which, even without NIF, will employ weapons scientists in design-related activities. The experience gained from the more than 1,000 nuclear tests the United States conducted before the cessation of such activities, plus the renewed testing that would clearly be warranted in such a crisis, would give the reconstituted design teams a huge database on which to draw.
Many scientists outside the defense arena find NIF very exciting. If successful, its increased power and greater implosion symmetry over Livermore’s NOVA could make it the first fusion facility to achieve ignition-a state in which more energy is produced than is needed to create the reaction in the first place. This would be an important milestone in the development of fusion power for civilian energy production. But there are two problems with using the prospect of civilian fusion experiments to justify NIF. One is a matter of prudence, the other a matter of public accountability.
Investing huge sums in a fusion facility is a risky proposition. For one thing, there is no guarantee that NIF, even with its 192 separate beams, can achieve the exquisite symmetry of implosion needed to produce an efficient fusion reaction. Timothy Coffey, director of research at the Naval Research Laboratory, who served on a 1994 NIF review panel, has expressed doubts about the prospects for success, adding: “If ignition is not achieved, then more than one billion dollars will have been wasted since the residual capabilities of the facility could have been far more easily achieved by different and much less expensive techniques.”
Exemplifying the technical difficulties the project could face, a glass lens in a NIF prototype laser imploded in September, causing the laser to be shut down for the second time in 17 months. Researchers have less than a year to correct the problem before construction begins.
Many other obstacles must also be overcome before fusion energy runs our refrigerators. Lasers are not expected to meet the requirements-efficiency, high rate of repetitive firing, and long lifetime-of a future fusion energy source. Other means of driving the reaction, such as a heavy-ion accelerator, may have to be developed. A 1995 Energy Departmentsponsored task force chaired by Robert Galvin of Motorola warned-even though it ultimately favored NIF-that “there is a low probability that inertial fusion will become a useful source of energy in the foreseeable future.”
Still, NIF has become a favorite of researchers in a number of basic and applied science areas. It could yield insights into supernovas, for example, as well as aid in the study of materials under high pressure, dense plasmas, and radiation sources. Prominent physicists recently wrote to Rep. Ron Dellums (D-Calif.), the ranking Democrat on the House National Security Committee, urging his support for the project on the grounds that it would be “important to fusion energy and basic science.”
This is where accountability comes in. NIF may be a great asset to fusion research and other fields, but it is not being funded as a basic-science tool. The facility has been promoted for its nuclear-stewardship role first and its civilian role second. So if the program’s real value stems from its contribution to basic science, then it ought to be subjected to the same funding criteria as other large basic-science projects. Would NIF survive close congressional scrutiny if it couldn’t hide behind a national security smoke screen? The cancellation of the superconducting supercollider is proof enough that expensive basic-science projects are a hard sell in Congress these days.
NIF and Proliferation
But if NIF is a waste of money or a less-than-straightforward use of public funds, is it actually harmful? From the standpoint of proliferation, it could be. Fusion research could further the spread of nuclear weapons, because the computer codes that are used to predict the behavior of the facility’s targets (the pellets that the laser beams fire on) are similar to codes for designing the fusion components of weapons. NIF would increase the number of scientists familiar with such codes in the United States and abroad.
Not only is NIF meant to be a multiuse facility open to international researchers (accessibility is one of its major selling points), but other nations such as Germany, Japan, and Israel have built or may build their own facilities for inertial confinement fusion. The Energy Department plans to institute some safeguards: scientists from states that have not signed the Nuclear Nonproliferation Treaty might be barred from using NIF, and the department could reject proposed experiments that are directly relevant to weapons development. However, since all experiments in inertial confinement fusion have some relevance to nuclear weapons, information control will be difficult.
The bottom line is that NIF would not by itself allow a nation to make a sophisticated nuclear weapon, but it could help build expertise. “Should a non-nuclear state decide to go nuclear,’ ” says Ray Kidder, a laser fusion pioneer and weapons physicist who recently retired from Livermore, “the existence of a cadre of people already experienced in many of the skills needed for designing nuclear weapons could, depending on the circumstances, materially reduce the time required to acquire them.” Just as the United States wants to use NIF to maintain a corps of experienced scientists, so might other nations use it to develop one.
On the other side, non-nuclear states that were involved in the Geneva talks on the Comprehensive Test Ban Treaty have ex-pressed serious concern that facilities like NIF will help nuclear states design new weapons without testing. India’s ambassador to the Conference on Disarmament, Arundhati Ghose, has warned: “The CTBT must be a truly comprehensive treaty, that is, a treaty which bans all nuclear testing without leaving any loopholes that would permit nu-clear weapon states to continue refining and developing their nuclear arsenals at their test sites and their laboratories.” The Department of Energy has sought to allay these concerns by stating that “NIF cannot proof-test any nuclear device and therefore cannot act as a replacement for full-up nuclear testing in the stockpiling of any nuclear weapons.”
This is true, but the stewardship program in its totality would provide U.S. weapons designers with more data than they have ever had, short of actual nuclear tests. The worry is that over time the labs may feel more confident about their ability to make changes to existing warheads-even to design all-new weapons-on the basis of computer simulations and experiments conducted at NIF and other facilities. On the one hand, the stewardship program tries to downplay this possibility, asserting in its “Programmatic Environmental Impact Statement” that “the issue of new-design weapons is separate from DOE’s need to perform modifications to existing weapons that require research, design, development, and testing.” On the other hand, the line between “modifications” and “new design” is not clear. Moreover, DOE admits that “it would be unreasonable to say that these stewardship capabilities could not be applied to the design of new weapons, albeit with less confidence than if new weapons could be nuclear tested.”
NIF’s implications for global security may be worrisome and its contribution to national security may be weak, but the project does have one strong suit: politics. NIF and the stewardship program are designed to secure support in the Senate for ratification of the comprehensive test ban. And because it may be years before the Senate considers CTB ratification, NIF could have plenty of time to soak up funds and begin construction. By that time, the proj-ect may be untouchable.
Or not. Once the test ban is ratified, congressional members looking to cut wasteful federal spending may see the program as an attractive target. If so, hundreds of millions of dollars would have been spent on a facility that may never be finished-the superconducting supercollider revisited. Instead of building expensive mega-facilities like NIF, the stewardship program needs to focus its resources on monitoring the stockpile and replacing suspect parts. The Energy Department could take a wait-and-see approach: continue to depend on the less powerful (but paid-for) NOVA laser for fusion-related experiments, and keep sample secondaries from older weapons under surveillance to find aging problems earlier than they would appear in the active arsenal. This way, we could wait for age-related defects to appear before breaking ground on NIF.
In the meantime, Congress should not let itself be fooled into believing that the facility is necessary for “national security.” NIF may be nice to have, but for the foreseeable future we can get along without it.
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