Plutonium Pits May Last Longer

* Recent research by Lawrence Livermore National Laboratory suggests that the plutonium pits contained in United States nuclear warheads may be reliable for significantly longer than previously expected. These results call into question the necessity for the Reliable Replacement Warhead program (RRW).

The United States government is confident in the reliability of the current nuclear stockpile. The original estimate for the lifespan of warhead plutonium was somewhere between 45 and 60 years. However, National Nuclear Security Administration (NNSA) chief Linton Brooks recently referred to unreleased research that suggests the plutonium pits in nuclear warheads may age better than previously expected. This new research demonstrates that the warheads will last 60 years or more.

Raymond Jeanloz, who chairs the National Academy of Science's International Security and Arms Control Committee, said "The remarkable finding is that key materials making up the nuclear explosive package are far more stable and predictable than anyone would have anticipated. Recent developments reinforce the conclusion that plutonium pits and the U.S. stockpile are stable over periods of at least 50 to 60 years and probably much, much longer."

Last year, Congress funded the RRW program to improve "the reliability, longevity, and certifiability of existing weapons and their components." Congress intended the program to extend the life of the existing stockpile without making significant enhancements to its capabilities.

However, it is unclear exactly what the RRW program will achieve. Brooks recently stated the long-range goals of the program. These are to develop technologies such that the nation would be able to adapt an existing weapon within 18 months and design, develop and begin production of a new design within three to four years of the decision to begin. Brooks said, "I will personally be very surprised if we can get the advantages we want without redesigning the [components of the bomb that create the nuclear reaction]."

The Department of Energy requested $6.41 billion for all nuclear stockpile activities for fiscal year 2007. They intend to use $27.7 million to support continued early research work for the RRW program and additional millions for programs such as an increased pit production capability which would allow new warheads to be produced as soon as 2012.

The increased plutonium pit production will take place at Los Alamos National Laboratory (LANL). Brooks recently announced that NNSA plans to increase LANL's manufacturing capacity to 30-40 pits by the end of 2012 in order to support the RRW program.

Brooks stated that the increased weapons design, development and production infrastructure would allow for a reduction in the total amount of weapons in the United States nuclear arsenal by reducing the amount of weapons maintained in case of unforeseen problems. However, Jeanloz, of the National Academy of Sciences, argued that the recent research on plutonium undermined the claim that the RRW was necessary to shrink the current nuclear arsenal. Jeanloz said, "To be sure, new phenomena may appear in the future, but these will be uncovered through ongoing work such as accelerated aging experiments. Meanwhile, the technical conclusion is that we do have time for a thorough and well-informed discussion of U.S. nuclear weapons policy."

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