The US Nuclear Weapons Complex: Major Facilities

Published Dec 5, 2012

Although the United States stopped producing new nuclear weapons over 20 years ago in the aftermath of the Cold War, the nuclear weapons complex (NWC), administered by the National Nuclear Security Administration (NNSA), is still a very active sector of the U.S. national security system.

With no new weapons being built, existing weapons must be carefully maintained and tested to ensure that they remain safe, reliable, and secure, and continual research must be conducted to ensure that knowledge about the nuclear arsenal remains as comprehensive and up-to-date as possible.

UCS has assembled fact sheets on eight key NWC facilities that perform these functions. Click on the facility names below to download the fact sheet PDFs.

(Note: budget and employee figures are approximate.)


Los Alamos National Laboratories

History: The birthplace of the U.S. nuclear weapons program, Los Alamos National Laboratory (LANL) was where the primary research, design and production of the first U.S. nuclear weapons took place. With the end of the Cold War and the declaration of a mortorium on full-scale nuclear testing in 1992, LANL's primary mission shifted from developing new warheads to maintaining the safety, security and reliability of the existing U.S. nuclear stockpile without nuclear testing.

Current work: LANL performs nuclear weapons research, design, and development; designs and tests advanced technology concepts; provides safety, security, and reliability assessments and certification of stockpile weapons; maintains production capabilities for limited quantities of plutonium components for delivery to the stockpile; manufactures nuclear weapon detonators for the stockpile; conducts tritium research and development (R&D), hydrotesting, high explosives R&D, and environmental testing; and currently maintains Category I/II quantities of SNM (substantial quantities of special nuclear materials that require the highest level of security).

Current issues: The Chemistry and Metallurgy Research Replacement Facility (CMRR-NF), a new building at LANL that would become the center of analytical chemistry and characterization of highly radioactive materials for the U.S. nuclear weapons complex, has seen its estimated costs rise sharply since the original estimate in 2004. Funding for the project has recently been cut, and the Obama administration announced a delay of at least five years in further construction work on the facility.

One of the benefits of the CMRR-NF project was supposed to be an increase in capacity to produce plutonium pits, the fissile core of the first stage of a modern, two-stage nuclear weapon. (The CMRR-NF would free up space in the facility that currently produces pits.) However, it is not clear that this additional capacity is really needed.


Lawrence Livermore National Laboratories

History: Established in 1952, Lawrence Livermore National Laboratories (LLNL) was created to aid in the research and development of nuclear weapons, competing in this mission with the Los Alamos National Laboratory (see below). LLNL designed the first nuclear warhead for a U.S. submarine-launched ballistic missile and the first warheads for multiple independently targeted re-entry vehicles (MIRVs). When the U.S. ended nuclear explosive testing in 1992, LLNL's primary mission shifted to stockpile stewardship.

Current work: Today, LLNL conducts regular evaluations of weapons it has developed: the W62 and W87 intercontinental ballistic missile warheads, the W84 ground-launched cruise missile warhead (now in the inactive stockpile), and the B83-01 bomb. LLNL's surveillance data, peer reviews, and results of experimental and computational simulations inform the Annual Stockpile Assessment by the Departments of Defense and Energy. LLNL is also the lead design lab for the W78 life extension program (LEP), even though that warhead was designed at Los Alamos.

LLNL's nuclear weapons-related tasks include nuclear weapons research, design and development; testing advanced technology concepts; plutonium and tritium research and development; hydrotesting and environmental testing; and high-explosives research and development.

Current issues: The National Ignition Facility (NIF), which houses the world's largest and most energetic laser, is located at LLNL. Its goal is to achieve "ignition," a carefully controlled thermonuclear explosion that would create the extreme temperatures and pressures found in nuclear weapons explosion under laboratory conditions. The project has been plagued by significant cost overruns and schedule slips, and its future is currently in doubt.

Large quantities of Special Nuclear Material (SNM), which includes both plutonium and weapons-grade uranium, have been stored at LLNL in the past. As part of a recent plan to consolidate and streamline the nuclear weapons complex, the NNSA had planned to remove all of this material from LLNL; however, it now appears that some plutonium will remain at LLNL for several more years. This is a particular concern because of LLNL's proximity to the heavily populated San Francisco Bay area and its population of 7 million.


Sandia National Laboratory

  • Location: Two sites—one near Albuquerque, NM, and one at Livermore, CA
  • Budget: $1.45 billion
  • Employees: 10,700
  • Download fact sheet

History: Sandia National Laboratory (SNL) grew out of Z Division, the ordnance design, testing, and assembly branch of Los Alamos during WWII. Z Division moved to Sandia Base, outside of Albuquerque, NM, to have easier access to an airfield and work more closely with the military. In 1948, Z Division became Sandia Laboratory, and in 1956 a second Sandia site was established in Livermore, CA; these two locations ensure proximity to the other two U.S. nuclear weapons research and design facilities—Los Alamos and Lawrence Livermore National Laboratories—that design the nuclear explosive packages for all U.S. weapons.

With the end of the Cold War and the 1992 moratorium on nuclear explosive testing, SNL's primary mission shifted from developing components to new nuclear weapons to maintaining the safety, security and reliability of the existing U.S. nuclear stockpile without nuclear testing.

Current work: Sandia's main weapons-related tasks include: systems engineering of nuclear weapons; research, design, and development of non-nuclear components of nuclear weapons; manufacture of some non-nuclear components; safety, security, and reliability assessments of stockpile weapons; HE research and development; and environmental testing.

Current issues: The Life Extension Programs (LEPs) that SNL conducts have raised some concerns. LEPs are intended to extend a weapon's life by 20 to 30 years by refurbishing, reusing, or replacing components affected by aging. Recent LEPs also investigate options to improve the safety, security, and reliability of the warheads (for example, by asdding use-control features. However, there is a danger that extensive changes to the nuclear explosive package could reduce confidence in the weapon's reliability.

Another concern has arisen in connection with the LEP for the B61 nuclear bomb. The LEP includes some changes to the bomb's design that some critics argue will add a new military capability, which would be contrary to the administration's assurance that LEPs "will not support new military missions or provide for new military capabilities."


Nevada National Security Site

History: The Nevada National Security Site (NNSS) is where the United States carried out most of its explosive tests of nuclear weapons. After the U.S. signed the Threshold Test Ban Treaty in 1974, NNSS became the only U.S. nuclear weapons test site. The site, located in the desert about 75 miles northwest of Las Vegas, is surrounded by an unpopulated area of more than 5,400 square miles, almost the size of the state of Connecticut.

Current work: After the 1992 moratorium on nuclear explosive testing, NNSS's primary mission shifted to stockpile stewardship. It is still a major test site for the U.S. nuclear complex, but the tests that take place there no longer involve nuclear explosions. NNSS is home to several unique facilities: The U1A complex, an underground laboratory where subcritical testing takes place; the Big Explosives Experimental Facility (BEEF); the Joint Actinide Shock Physics Experimental Research (JASPER) facility; the Device Assembly Facility (DAF); and the National Criticality Experiments Research Center (NCERC).

Current issues: The decision to delay construction of the Chemistry and Metallurgy Research Replacement-Nuclear Facility (CMRR-NF) at Los Alamos National Laboratory (see above) had raised concerns that an alternative storage site might be needed for nuclear materials that had been slated for storage at CMRR-NF. However, it has been suggested that the DAF at NNSS could be used for this purpose; it has considerable unused space and the safety and security features required to store plutonium.

NNSS has also been proposed as a backup facility to the Pantex Plant for disassembly of retired nuclear weapons. Because disassembly requires some of the same facilities as Life Extension Programs (LEPs), a recent increased emphasis on LEPs has slowed weapons disassembly at Pantex and created a backlog which NNSS could fill.


Pantex Plant

History: Originally a World War II Army site for assembling artillery shells and boms, Pantex reopened in 1951 as a facility to handle nuclear weapons, high explosives, and non-nuclear component assembly operations. Since 1975, it has been the only facility in the U.S. where nuclear weapons are assembled and disassembled. After 1991, its mission shifted from assembling nuclear weapons to refurbishing existing warheads to extend their lifetimes and disassembling retired weapons.

Current work: Under the Stockpile Stewardship Program (SSP), Pantex conducts life extension programs (LEPs) on existing weapons, so far including the W87 and W76 warheads and B61 bombs. Additional LEPs are planned, some more far-reaching than those done to date. In addition, Pantex's work includes dismantling retired warheads; interim storage, "sanitizing" (removing classified information), and disposal of dismantled weapon components; and R&D, production and testing of high explosives used in nuclear weapons.

Current issues: Disassembly of retired warheads has slowed at Pantex in recent years, in part because of increased emphasis on LEPs; disassembly and LEPs compete for some of the same facilities.

Pantex is currently predicted to reach its maximum planned capacity for storage of plutonium pits in 2014, and remain over capacity until 2022. Originally, NNSA had planned to deal with the crunch by building a new underground storage facility; however, a 2008 study suggested that the new facility would not be ready in time, and recommended modifications to existing facilities to increase storage capacity.


Kansas City Plant

History: The Kansas City Plant was originally built to provide aircraft engines for Navy fighters in World War II. In 1949 it began producing nonnuclear components of nuclear weapons for the Atomic Energy Commission. With the end of the Cold War and the 1992 moratorium on nuclear explosive testing, KCP's mission shifted from producing parts for new nuclear weapons to supplying new components for existing weapons in support of the Stockpile Stewardship Program.

Current work: KCP produces or procures more than 100,000 parts annually, including a wide range of mechanical, electronic, electromechanical, metal, and plastic components. KCP is also responsible for testing and evaluating the parts it produces. In addition, KCP participates in life extension programs (LEPs) and limited lifetime component exchange (LLCE) for stockpile weapons. No special nuclear material (weapons-usable plutonium or highly enriched uranium) is kept on site.

Current issues: The plant is currently scheduled to move into a new facility at a nearby site by 2014. The move is part of a project to reduce operating costs and increase the plant's flexibility in meeting demand for nonnuclear components. Part of the cost-reducing effort will include increasing the percentage of component production that is outsourced to commercial manufacturers. However, the Government Accountability Office has raised concerns that the plan may lead to outsourcing of more complex, specialized components, which could increase proliferation risk because information about the components' design and manufacture could get into the hands of potential adversaries.

The move to the new facility will also require a comprehensive environmental assessment and remediation before the old site can be sold to a private company for development.


Savannah River Site

History: For most of its history, the Savannah River Site (SRS) produced radioactive materials for the U.S. nuclear weapons program. Due to the large amounts of radioactive waste the site's activities have generated over the years, it was declared a Superfund site. With reductions in the U.S. nuclear arsenal after the end of the Cold War, SRS's mission shifted to maintaining the current arsenal, disposing of excess nuclear materials, and cleanup of the site.

Current work: SRS is responsible for replenishing the supply of tritium gas that is used to boost the yield of nuclear weapons. SRS stopped producing tritium in 1988; to meet current needs, it recycles tritium from dismantled warheads and extracts tritium produced in the Watts Barr nuclear power plant in Tennessee. SRS also performs reliability testing on the gas transfer systems that inject tritium-deuterium gas into the plutonium pit as the weapon's fission reaction begins.

SRS also disposes of surplus plutonium—converting it plutonium oxide for use in mixed oxide (MOX) fuel—and highly enriched uranium (HEU), which is separated and blended with natural uranium to create low-enriched uranium (LEU) fuel. MOX and LEU fuel can be used in commercial nuclear reactors.

Current issues: A pit disassembly and conversion facility (PDCF)—which removes plutonium from dismantled nuclear weapons and converts it to plutonium oxide for MOX fuel—was planned for SRS until recently; however, Congress declined to fund the project, and existing facilities at SRS and Los Alamos will be expanded to meet this need.

A mixed oxide fuel fabrication facility (MFFF), begun at SRS in 2007, has run into problems. Costs have increased significantly since the project was first planned, while the market for the MOX fuel the facility would produce is uncertain, since converting commercial reactors to use MOX fuel requires time-consuming testing procedures and also opens up new safety and security issues.

Delays in building the MFFF have added to concerns about a buildup of surplus plutonium at the SRS site. Some of this plutonium, which is too impure to use in MOX fuel production, was supposed to be transferred to a permanent repository; however, the Obama adminstration's decision to abandon plans for the Yucca Mountain repository has sparked concerns that the surplus plutonium may end up being stored at SRS indefintely.


Y-12 National Security Complex

History: The Y-12 National Security Complex was part of the original Manhattan Project, producing enriched uranium for the "Little Boy" bomb dropped on Hiroshima in 1945. The site takes its name from the World War II code name for the electromagnetic isotope separation plant at the Clinton Engineer Works in Oak Ridge, TN. During the Cold War, Y-12 enriched uranium through electromagnetic separation and later gaseous diffusion and manufactured nuclear weapons components from uranium and lithium.

Current work: Today Y-12 is one of four production facilities in the U.S. nuclear weapons complex. It produces the "secondaries," the final and most powerful explosive stage, for all U.S. nuclear weapons. In addition, Y-12 performs quality evaluation and surveillance on subassemblies and components; maintains quantities of highly enriched uranium (HEU) for weapons use; dismantles secondaries and other weapons components; and stores and disposes of enriched uranium. Y-12 has completed work on life extension programs (LEPs) for two weapons: the W87 intercontinental ballistic missile warhead and the B61-7 and B61-11 strategic nuclear bombs. Y-12 also supplies the Navy with HEU from dismantled weapons to make fuel for use in the nuclear reactors that power all U.S. submarines and aircraft carriers.

Current issues: A new uranium processing facility (UPF) is planned for the Y-12 site, on a scale that could produce 50 to 80 secondaries per year; however, no decision has been made yet about producing secondaries for future LEPs, so it is not clear whether this level of production is needed. (In an LEP, secondaries may be refurbished, remanufactured, or replaced.) In addition, schedules have slipped and cost estimates have risen significantly on the UPF project, culminating in the October 2012 discovery that the facility's $500 million design would need to be revised to make the roof higher and the foundation and walls thicker.

There have also been security woes at Y-12; a July 2012 incident in which antinuclear protesters were able to enter the complex's highest-security area prompted an Inspector General's investigation that led to several firings, increased security training for employees, and a temporary suspension of nuclear weapons activities at the complex.

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