Planning for future refurbishment and
manufacturing needs of the U.S. nuclear
weapons complex critically depends
on credible estimates for component
lifetimes. One of the most important
of these components is the pit, that
portion of the weapon that contains
the fissile element plutonium. The U.S.
government has proposed construction
of a new Modern Pit Facility, and a key
variable in planning both the size
and schedule for this facility is the
minimum estimated lifetime for stockpile
pits. This article describes the current
understanding of aging effects in
plutonium, provides a lifetime estimate
range, and outlines in some detail
methodology that will improve this
estimate over the next few years.
