NNSA demonstrates transparency in its operations and support for the Comprehensive Nuclear Test Ban Treaty by hosting visitors at Sandia and Nevada site

At NNSS, the visitors saw a variety of projects supporting nonproliferation technology research and development. At one stop, the visitors entered P Tunnel, the site of a recent nonproliferation experiment using chemical explosives and radiotracers to advance the state-of-the-art in nuclear explosion monitoring with improved understanding of geophysical and radiochemical science and data analytics techniques.

Visitors also saw projects associated with the science-based Stockpile Stewardship Program, established more than 20 years ago in the wake of the United States' 1992 moratorium on underground nuclear explosive tests. The program relies on specialized facilities, supercomputers, subcritical experiments, technical experts, and other scientific capabilities to ensure the safety, security, reliability, and effectiveness of the U.S. nuclear stockpile without the use of nuclear explosive testing. During this and other similar visits, the United States has been transparent about activities at NNSS such as the work done at the Principal Underground Laboratory for Subcritical Experimentation (PULSE, formerly known as the U1a Complex), the site of U.S. subcritical experiments.