Nuclear Weapons:

Year 2000 Status of the Nation's Nuclear Weapons Stockpile

RCED-99-272R: Published: Aug 20, 1999. Publicly Released: Aug 20, 1999.

Additional Materials:


James E. Wells, Jr
(202) 512-6877


Office of Public Affairs
(202) 512-4800

GAO reviewed the actions the Department of Energy (DOE) and its contractors have taken to determine if any year 2000 problems exist with the nation's nuclear weapons or supporting ancillary equipment.

GAO noted that: (1) based on GAO's review of documents and the discussions GAO held with weapon design engineers, GAO believes the nuclear weapons in the nation's enduring stockpile will not be affected by the year 2000; (2) only four of the weapons in the enduring stockpile contain microprocessors; (3) the microprocessors in these weapons do not rely on an internal clock that is aware of the actual date to carry out the timing functions necessary for the weapons to perform as designed; (4) instead, the weapons perform their timing functions through the use of an analog timing source, external to the microprocessor, that keeps relative time--similar to a stopwatch; (5) most of the ancillary equipment associated with nuclear weapons either do not have a year 2000 problem, have been replaced by year 2000-compliant equipment, or have an acceptable work-around; (6) however, one type of test equipment at Pantex--where assembly, disassembly, and surveillance of nuclear weapons is conducted--and one type of test equipment at the Kansas City Plant--where parts for nuclear weapons are made--are noncompliant as of August 1999; (7) according to DOE and contractor officials, this test equipment is expected to be fixed by January 1, 2000; (8) although GAO did not identify year 2000 problems with the nation's nuclear weapons, GAO did identify process and documentation weaknesses; (9) specifically, the process for designing, assessing, and certifying nuclear weapons is highly structured in order to ensure that the weapons remain safe and reliable; (10) this process includes extensive documentation and peer review; (11) however, DOE and Sandia National Laboratories management did not require this same level of rigor for the nuclear weapons year 2000 assessment; and (12) consequently, the reviews performed were often unstructured, did not always include thorough documentation, and were subjected to minimal peer review.

Recommendation for Executive Action

  1. Status: Closed - Implemented

    Comments: In a November 10, 1999, letter, the Acting Assistant Secretary for Defense Programs stated that DOE had complied with the recommendation and that the Sandia National Laboratory had documented the Y2K assessments it had performed on the nuclear weapons stockpile.

    Recommendation: To serve as a basis for the certification of year 2000 readiness of nuclear weapons, DOE should require Sandia National Laboratories to thoroughly document the year 2000 assessments performed, including the scope of the assessments; documents, diagrams, and software reviewed; discussions held; and logic used.

    Agency Affected: Department of Energy


Explore the full database of GAO's Open Recommendations »

Oct 16, 2017

Oct 5, 2017

Sep 29, 2017

Sep 28, 2017

Sep 27, 2017

Sep 26, 2017

Sep 19, 2017

Sep 12, 2017

Looking for more? Browse all our products here