The mission of the National Nuclear Security Administration's (NNSA) Off-site Recovery Project (OSRP) is to recover unwanted radioactive sealed sources (sources) held in the piblic sector. thereby reducing the threat of the sources being used in radiological dispersal de\iices or a "dirty bomb." Plutonium-239 (Pu-239), one of the rildioactive sealed sources recovered by OSRP, requires additional safeguards because ~t is a special nuclear material. These sources were manufactured in the United States (Li S.) and loaned or leased to colleges and universilies, commercial companies and other coiintries by the Atomic Energy Commission. Due to the fact that they are on loan, they remain the property of the Department of Energy. As of May 2006, there were 772 outstanding Pu-239 sources, ecli~alinga pproxi~nately2 '7,300 grams that the OSRP had ycr to recover