NNSA Restores Nuclear Weapon Pit Manufacturing Capability

Press Release
Jul 2, 2007
NNSA's Los Alamos National Laboratory undergoes 10-year effort to completely rebuild key nuclear weapons component

LOS ALAMOS, NM -- The Department of Energy's National Nuclear Security Administration (NNSA) today recognized the production of the first replacement pit in 18 years for a nuclear weapon. An essential piece of every U.S. nuclear weapon, the pit is typically made of plutonium and acts as a trigger, allowing a weapon to function. The pit was built for the W88 nuclear warhead ahead of schedule and under budget by NNSA's Los Alamos National Laboratory, with support from other sites in the nuclear weapons complex.

"Having this capability means that we can maintain the safety, security and reliability of the W88 nuclear weapon without having to conduct underground nuclear tests," said NNSA's Acting Administrator Bill Ostendorff. "This achievement could not have been possible without the tremendous scientific and technical expertise at NNSA's Los Alamos National Laboratory and the very important contributions from the rest of the nuclear weapons complex."

After the Rocky Flats Plant in Colorado stopped production in 1989, the country lacked the capability to manufacture pits, also called primaries, for the stockpile. However, under its Stockpile Stewardship Program to ensure the reliability, safety and security of the weapons without underground nuclear testing, NNSA regularly takes apart and examines weapons. Most of the weapons are reassembled and returned to the stockpile through this process, but some of the inspections are so thorough that the pit and other components must be destroyed. An insufficient number of W88 pits were manufactured at Rocky Flats to allow for the necessary destructive evaluations. Thus, replacement pits are needed to provide continued confidence in the current W88 stockpile.

Because the Los Alamos laboratory had the only remaining complete plutonium manufacturing capability in the country, it was tasked in 1996 with recreating the W88 pit that was built at Rocky Flats. This led to a 10-year effort to plan, develop, design, build, qualify and guarantee a replacement W88 pit process at Los Alamos. In 2000, NNSA established an office and project schedule to build and certify the first pit by September 2007. The capability for the W88 pit culminated with NNSA's recent certification for inclusion into the stockpile.

"This success is due to dedication and hard work by the people of Los Alamos National Laboratory," said Michael Anastasio, laboratory director. "Meeting technical, scientific, and manufacturing challenges is what this laboratory is all about. I am very proud of the work and of everyone involved in this important accomplishment."

By using small-scale plutonium experiments, data from past underground nuclear tests, groundbreaking materials science, extensive statistical analysis and adapting computer codes, Los Alamos was able to guarantee the structural and thermal integrity of the pit, ensuring it will have the same reliability and performance as the original pit. More than 900 laboratory personnel contributed to the effort, which included developing and qualifying 100 different production processes and installing more than 20 major pieces of manufacturing equipment.

In addition to Los Alamos, other parts of NNSA's nuclear weapons complex contributed to the efforts. The Lawrence Livermore National Laboratory supplied radiographic inspection capabilities, produced small scale plutonium samples for testing and provided engineering evaluations and technical peer reviews. The Kansas City Plant provided engineering support and tooling manufacture expertise to streamline the project. Sandia National Laboratories supported manufacturing and calibration efforts.

The W88 pit has been sent to NNSA's Pantex Plant for installation into a warhead. Los Alamos is on schedule to make 10 W88 pits each year. In order to keep up with the certification demands of the stockpile, the laboratory is on track to demonstrate with its pit manufacturing capability that it has the capacity to make 30 to 50 pits per year by the end of the 2012 to 2014 timeframe.

Established by Congress in 2000, NNSA is a separately organized agency within the U.S. Department of Energy responsible for enhancing national security through the military application of nuclear science. NNSA maintains and enhances the safety, security, reliability and performance of the U.S. nuclear weapons stockpile without nuclear testing; works to reduce global danger from weapons of mass destruction; provides the U.S. Navy with safe and effective nuclear propulsion; and responds to nuclear and radiological emergencies in the United States and abroad.

Media contact(s):
NNSA Public Affairs (202) 586-7371