The cessation of nuclear testing in 1992 created the need for a method of insuring both the safety and reliability of the nation's nuclear stockpile. Based on the scientific and technical capabilities of Los Alamos and the other national laboratories, the Department of Energy created the Stockpile Stewardship Program. As former Los Alamos Director Sig Hecker stated in 1995, "Reducing the nuclear danger stall calls for stewardship of the existing nuclear weapons stockpile: keeping those weapons that the nation needs safe, secure, and reliable"
The Department of Energy's stockpile stewardship program has three main elements: science, surveillance, and production. Science-based activities provide data to validate advanced nuclear weapons simulation codes. Surveillance activities use chemical, analytical, and material sciences to assess the aging of stockpile components. Production activities involve maintaining the nation's capacity to produce nuclear weapons components (to replace aging parts). As former Secretary of Energy Bill Richardson stated in 1999, "The stockpile stewardship program is a cornerstone of our national security."
Los Alamos contributions to stockpile stewardship include the development of the Blue Mountain supercomputer (one of the world's fastest machines) and the computational methods it uses. Other initiatives include the production of replacement pits for the current stockpile and the completion of the Dual-Axis Radiographic Hydrodynamic Test Facility, which will provide high-resolution imaging for understanding weapon performance. As another former Los Alamos Director stated in 1999, "Maintaining the viability of the stockpile in the absence of nuclear testing is an enormously difficult challenge, but we are using very powerful tools today to certify the stockpile, and every day we are enhancing our stewardship tools with even more advanced capabilities."