Panel Questions Warhead Concept Plausibility

Wade Boese

• U.S. Nuke Dismantlement Tops Goal for Year

The jury is still out on whether the United States can develop a new nuclear warhead without using a test explosion to verify its performance, a leading scientific panel has concluded, urging further study. Meanwhile, two key congressional protagonists in the debate surrounding the controversial initiative announced they will not seek re-election next year.

Lawmakers last year requested a review of the feasibility of the Reliable Replacement Warhead (RRW) program by JASON, an advisory group of scientists that the U.S. government often commissions to conduct studies. Launched in 2004, the program aims to develop a warhead that is supposed to be less susceptible to accidents or misuse and easier and safer to build and maintain than existing warheads. The design is supposed to be validated without nuclear testing, which the United States ceased in 1992.

In an unclassified executive summary of its report dated Aug. 29, JASON concluded that it remains unknown if such a warhead can be produced and guaranteed to work. The scientists stated, “[C]ertification is not yet assured.” They added, “[T]he certification plan presented needs further development.”

The Department of Energy’s semi-autonomous National Nuclear Security Administration (NNSA), which oversees the RRW program and the full nuclear weapons complex, portrayed the study as affirming the agency’s approach. In a Sept. 28 press release, Thomas D’Agostino, the NNSA director, said he was “pleased” the group “feels that we are on the right track.”

Others interpreted the study differently. Representatives Pete Visclosky (D-Ind.) and David Hobson (R-Ohio) issued a Sept. 27 statement declaring, “Once again, independent sources have raised serious questions that must be addressed before proceeding with the RRW [program].” The two legislators are the top members of the House appropriations energy and water development subcommittee, which earlier this year zeroed out the NNSA’s nearly $89 million fiscal year 2008 budget request for the RRW program. The full Congress has yet to agree on a final funding level.

The JASON report summary specified elements of the NNSA process requiring improvement and areas where uncertainties cast doubt on the program’s future.

In general, JASON urged the NNSA to grant peer review a “larger role” than the agency had planned. The scientists said a concerted effort should be made to “assure the nation that all expertise available has been applied to a rigorous evaluation of the new design.”

One aspect of the new design meriting greater scrutiny, according to JASON, is the effort to make the warhead more impervious to unintended or unauthorized detonation. “Substantial work remains on the physical understanding of the surety mechanisms,” the report noted.

JASON also suggested the NNSA delve more into pinpointing potential “failure modes” of the new design, which is based in part on previously tested systems. The scientists called for the NNSA to supplement its current certification plan with “additional experiments and analyses” to assess what might cause the design to fail. In particular, the study said the agency should investigate how proposed new manufacturing processes for an RRW device might affect performance.

Since enacting its nuclear test moratorium, the U.S. government has maintained confidence in the capability of its nuclear weapons through extensive surveillance, life extension, and computer simulation and modeling activities under the Stockpile Stewardship Program. The simulation and modeling work is based partially on data gleaned from previous nuclear tests of the nine basic warhead types currently making up the roughly 10,000 warhead stockpile, which is slated to be cut almost in half by 2012 under an initiative announced in June 2004 by the Bush administration. (See ACT, July/August 2004. )

RRW advocates contend that the new warhead design under development will be simpler than existing warheads and should be certifiable, given growing simulation and modeling capabilities. The JASON report, however, cautioned that “it is not yet possible to quantify how well excursions from a tested design can be modeled and predicted.”

A rationale advanced by the administration for embarking on the RRW initiative is that the small changes made to existing warheads through current life-extension activities will gradually move the warheads away from their original composition, raising questions about the possible performance of the warheads. Still, current warheads have been judged annually by the stewardship program as safe and reliable. JASON noted that it was not tasked with comparing “the merits of the RRW program relative to other options, such as life-extension programs.”

Using the stewardship program, the NNSA for the first time recently completed certification of a rebuilt warhead pit, which is the core component of a warhead that triggers the start of the nuclear explosion. The effort to rebuild and validate the W88 warhead pit took more than a decade. In a Sept. 27 press release, the NNSA declared that “certification was possible because of NNSA’s powerful experimental tools, supercomputers, and improved computer models.”

Whether the stewardship program is sufficient for maintaining the stockpile or the RRW program is needed has been sharply debated in Congress. To date, skeptics of the RRW effort have prevailed in trimming funding and capping research on the project, and they are poised to do so again this year in the current crop of congressional bills. (See ACT, July/August 2007. ) The Pentagon, however, sent an Oct. 10 letter to key members of Congress appealing proposed RRW funding cuts in the fiscal year 2008 defense authorization bill.

One lawmaker the Pentagon and the nuclear complex have generally relied on to strongly promote their causes will be departing Congress at the end of next year. Senator Pete Domenici (R-N.M.), who has served 35 years, announced Oct. 4 that he will not seek re-election because of health reasons. New Mexico is home to two national nuclear laboratories, and Domenici has pressed hard for the RRW program, calling for it to be expanded beyond the initial version to a second design as well.

One of Domenici’s foremost opponents on nuclear weapons funding the past several years has been Hobson, who announced Oct. 14 that he also will not run again. Hobson, who is serving his ninth term in the House, has railed against what he sees as an obsolete, excessive, and wasteful nuclear complex and contends that the United States needs to rethink its nuclear policies before developing new nuclear warheads, such as the RRW.

One congressional staffer noted to Arms Control Today Oct. 16 that the two lawmakers occupy opposite ends of the spectrum but that the differences dividing them are not going to disappear with their departures. Those issues, the staffer said, will persist in “serious and profound ways.”