Skip to main content

Currently Skimming:

1. Stockpile Stewardship Considerations: Safety and Reliability Under a CTBT
Pages 19-34

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 19...
... . ~ ~ ~ _ This program is intended to ensure the continued safety, reliability, and operational readiness of the enduring stockpile, without nuclear testing, for as long as national policy dictates a need for such weapons.2 The SSP places increased emphasis on strengthening the scientific understanding of nuclear device performance as well as the aging behavior of weapon materials and components.
From page 20...
... It is assumed explicitly that the enduring stockpile will not depend on the introduction of new nuclear subsystem designs that would require nuclear testing for performance validation. However, the SSP is required to maintain the capability for executing new designs should a compelling need ever arise for such.
From page 21...
... . Since these tests primarily established confidence in the stockpile system as it was initially produced, validating the integrated performance of the nuclear subsystem at stockpile entry, they should be described more correctly as "production verification" tests.
From page 22...
... But previously tested nuclear subsystems or components of these could be used in modified or entirely new delivery systems, provided that any influences of the altered system on the nuclear subsystem were deemed to be within acceptable limits in the light of prior nuclear-test experience. The key constraint on deployment of additional nuclear weapons of previously tested designs under a CTBT, should the country wish to do this, would not be the absence of the ability to conduct new nuclear tests but the lack of capacity for manufacturing new primary pits.
From page 23...
... For abnormal-environment stockpile-to-target sequence scenarios one-point nucleardetonation safety is the only safety criterion that hinges on the nuclear perfo~ance of the nuclear subsystem. (This criterion specifies that the probability of a nuclear yield greater than 4 pounds TNT equivalent must not exceed ~ o-6 in the event that a detonation is initiated at any point in the high explosive surrounding the primary.)
From page 24...
... There are no plans to retrofit weapons lacking ENDS because it is anticipated that these watt in time be retired from the stockpile. While the probability of inadvertent nuclear detonations has been reduced by modern electrical-subsystem designs to acceptably low levels there still remains the threat of plutonium dispersal in accidents.
From page 25...
... This has permitted an approach to guaranteeing reliable operation in which the manufacture of the nuclear components and their assembly is carefully controlled within tight tolerances, yielding production versions that replicate devices whose pedigree was established through nuclear tests during the development phase. Periodic inspection of nuclear subsystem parts from weapons withdrawn randomly from the stockpile, together with remedial action when required, ensures that conformance to specification is maintained over time.
From page 26...
... Weapon reliability is dominated by the non-nuclear system elements, which are testable under a CTBT; and (2) Confidence in the continued reliability of the nuclear subsystem can be maintained by ensuring that in any future rebuilds, especially of the primary, the original specifications are adhered to closely.
From page 27...
... Despite best efforts it is likely to prove impossible in the future to adhere exactly to the original material and process specifications in the remanufacture of nuclear components. Any changes in the specifications will have to be of a nature that does not perturb in a significant way the nuclear-test pedigree of the design, that is, they will need to remain well within the range of parameters where subsystem behavior is understood based on ~ a ~~~~ ~~,,-r -- -- , 9 In preparing the certification report, the Secretary of Energy receives assessments from the Directors of the three weapon laboratories and the Secretary of Defense receives assessments from the Strategic Command and the military services.
From page 28...
... These tools are intended to yield a more complete understanding of weapon performance and potential failure modes for nuclear as well as non-nuclear components and subsystems. This effort represents a continuation of the traditional knowledge-based approach to problem solving in the nuclearweapon program, albeit at a significantly accelerated rate of progress.
From page 29...
... Although a properly focused SSP is capable, in our judgment, of maintaining the required confidence in the enduring stockpile under a CTBT, we do not believe that it wall lead to a capability to certify new nuclear subsystem designs for entry into the stockpile without nuclear testing—unless by accepting a substantial reduction in the confidence in weapon performance associated with certification up until now, or a return to earlier, simpler single-stage design concepts, such as gun-type weapons. Our belief that the introduction of new weapons into the stockpile will be restricted to nuclear designs possessing a credible test pedigree is not predicated on any conjectures as to the likelihood of DARHT, NTF, ASC, or other major facilities achieving their design goals.
From page 30...
... Nuclear-Subsystem Remanufacturing Capability Remanufacture to original specifications is the preferred remedy for the age-related defects that materialize in the stockpile. This makes it essential that a capability to remanufacture and assemble the nuclear subsystems for nuclear weapons be maintained in the U.S.
From page 31...
... Non-nuclear Component Development and Manufacture Since the non-nuclear components and subsystems external to the nuclear subsystem can be fully tested under a CTBT, it is possible to incorporate new technologies in these weapon parts as long as these can be shown not to have any adverse effect on proper functioning of the nuclear subsystem. In fact, it would be very costly to replace some non-nuclear components with exact copies as changeouts become necessary.
From page 32...
... As indicated above, we believe it would not be possible to certify new-type nuclear subsystem designs for entry into the stockpile without nuclear testing—unless by accepting a substantial reduction in the confidence in weapon performance associated with certification up until now, or a return to earlier, simpler, single-stage design concepts, such as gun-type weapons. Thus, if not only design but also certification for entry into the stockpile of sophisticated new nuclear-weapon types were deemed necessary in the future in the national interest, and a CTBT were in force, we judge that the United States would need to withdraw from the treaty in order to conduct the nuclear tests needed for certification.
From page 33...
... in order to avoid the introduction of interference effects between nuclear and non-nuclear components, prudence dictates that a similar discipline be practiced in regard to any design changes or changes in location of non-nuclear components in proximity to the nuclear subsystem. Priorities in Stockpile Stewardship DOE's Stockpile Stewardship Program addresses all of the critical areas identified above, including plans for an aggressive "Stockpile Lifetime Extension Program" (SEEP)
From page 34...
... Evaluation of the acceptability of age-related changes relative to original specifications and the cumulative effect of individually small modifications of the nuclear subsystem should also be subject to periodic independent review. Such reviews, involving the three weapon laboratories and external reviewers, as appropriate, would evaluate potential adverse effects on system performance and the possible need for nuclear testing.


This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More information on Chapter Skim is available.