Development of plasma based decontamination of large metallic objects

Summary form only given. The United States Department of Energy complex has a significant legacy of equipment which has been used in the production of the nations nuclear weapons stockpile, and is consequently contaminated with Transuranic (TRU) material. Portions of this equipment set (glove boxes, ventilation ducts, large pipes, etc.) consist of relatively large, often geometrically complex items with significant levels of surface or near-surface TRU contamination. Present methods for decontamination and disposal of these items typically involve surface scrubbing (with various solvents or acidic solutions, high pressure water jets, etc.), followed by size reduction (cutting the object into smaller pieces), and packaging for ultimate disposal in a facility such as the Waste Isolation Pilot Plant (WIPP). The present decontamination methods are often crude-involving significant possibility for exposure of personnel to radiation, and frequently generating large quantities of contaminated liquid waste, which must be processed before re-use or disposal. A dry decontamination process using Reactive Ion Etching (RIE) with a fluorine and oxygen based plasma is being developed at Los Alamos National Laboratory as an improved method for removal of TRU material from the surface or near-surface of large metallic objects.