The recurring loss, theft, or misplacement of radioactive sources, worldwide in scope, has long been an issue for public health and law enforcement officials.

Now, with the added potential for their use in radioactive dispersal devices (RDDs), or so-called "dirty bombs," officials view them as much more of a threat. Such a bomb detonates conventional explosives to scatter radioactive material across a target area. Dirty bombs, experts acknowledge, are likely to cause as much or more damage from fear and reaction to fear as from the dangers of the explosives or the radioactive materials themselves.

Clipping Collection

Joe Schelling, of Sandia's Program Development and Environmental Decisions Department, keeps a collection of news items that suggest the problem. One tells of a small, yttrium-90 sealed source was left in a New York taxicab. It was later recovered. Others tell how radioactive cesium chloride, removed from a sealed source, found its way into the hands of children in Brazil. At least four deaths and the destruction of part of a town, including businesses and 85 homes, resulted. Others detail a regular pattern of losses or misplacement of sealed sources.

"After 9/11, people in government started asking 'where is this stuff (sealed sources) in the country?' and nobody had a good answer," says Schelling. "We definitely started paying attention to missing radioactive sources because of the RDD potential," says Lori Dotson, who is managing Sandia's project to better control the more than two million government and commercial sealed radioactive sources in the US.

Enter RSRT

The project, called the Radioactive Source Registry Tracking System (RSRT), will first track all DOE sealed radioactive sources and provide decision makers with some estimation of the potential threat they may pose. The system is being coordinated with the Nuclear Regulatory Commission (NRC) and the International Atomic Energy Agency to be consistent with national and international source tracking needs.

Following reports from an International Conference on Security of Radioactive Sources in Vienna, Austria, in March 2003 and from the DOE/NRC Interagency Working Group on Radiological Dispersal Devices in May 2003, the Secretary of Energy chartered DOE's Office of Plutonium, Uranium, and Special Materials Inventory (SO 62) to create a database for tracking sealed sources.

The Sandia team's effort has resulted in an initial RSRT system well ahead of schedule, notes Gary "G.D." Roberson, DOE project manager. With anticipated increases in funding over the next few years, he expects the system to make a significant contribution. "It is already significant in the sense that the DOE has a database that is a direct commitment to the charter and is up and running."

Responding to the May charter from Secretary Spencer Abraham, Sandia team members built the RSRT system by using existing data and databases and adding other sealed source data from throughout the DOE complex. "Sandia had an operational database with some 55,000 entries called the National Inventory of Sealed Sources, which contained select nuclear materials, actinide isotopes, and sealed sources," explains Schelling.

Aggressive Milestones

The Sandia team set aggressive milestones to demonstrate that it could deliver an online system to meet the immediate needs of the new charter. The team met the first milestone late last year, six weeks ahead of schedule, by placing the interim RSRT online.

Federal regulations set limits on the types of radioactive material that must be controlled. The Sandia system uses those limits as a baseline. Now, acquiring data becomes critical to the ultimate success of the RSRT program. Idaho National Engineering and Environment Laboratory is supporting the team by leading the data acquisition effort.

The team's goal is to track all DOE sealed sources by March 31.

Currently, DOE is the primary user of the system, but DOE has also offered it to the Department of Homeland Security, the Federal Bureau of Investigation, and the Environmental Protection Agency for use as a tool to support tracking, assessment, and recovery of sealed sources.

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