Rapid Dissolution for Destructive Assay of Nuclear Melt Glass

This study evaluates four methods for dissolving complex glassy debris resulting from nuclear detonations. The samples of interest simulate the glassy debris generated from a nuclear detonation’s fireball coming in contact with solid masses. Each method attempts to achieve dissolution through different approaches involving either acid digestion, alkaline digestion, or molten salt fusion. Two of the four methods were modified to retain all elements of the debris or surrogate debris. This retention is critical to the proportional relationships used in identifying fuel types and designs of nuclear weapons. Analysis is conducted with an inductively coupled time of flight mass spectrometer (ICP-TOF-MS) to provide exact elemental composition and yield for each dissolution method. The samples analyzed were trinitite (trin), surrogate trinitite formulation (STF), urban surrogate melt glass (NYC), and MAPEP MaS 32 (MAPEP). All samples have well known elemental compositions except for trinitite, however there are published compositional norms that are predicted for the trinitite. The four methods used were a Lithium Fusion (Larivière Method), a Sodium Hydroxide Fusion (Maxwell Method), an Acidic Digestion (Eppich Method), and a Modified Rapid Acidic Digestion (Auxier Method). Outcomes for the Lithium and the Maxwell Method failed to produce meaningful results due to the mass difference in fusion material compared to the isotopes of interest in the sample material mass. At the maximum concentration limit of 25-35 parts per thousand the mass spectrometer could not meaningfully detect the barium or uranium in any of the samples. The acidic digestion, and the Auxier Method both showed success with detecting appropriate levels of uranium, barium, and other lighter elements. The Auxier Method shows the best results when compared to ideal 100% yield from each sample. For Auxier’s Method, uranium averages a yield of 5%±.02% of ideal. This is 614% above the acidic digestion and over 1200% above the other methods. For barium, the Auxier Method averages a yield of 9% of ideal. This is 595% above the acidic digestion and 4300% above the other methods. The Auxier Method demonstrates repeatability across three runs of each sample and sample independence as percent yields were similar across sample types.