Cleaning up after major dirty bomb attack

A new study, scheduled to appear in the May 1 edition of Environmental Science & Technology, a peer-reviewed journal of the American Chemical Society, the world's largest scientific society, suggests that current regulations for environmental remediation are inadequate to deal with a dirty bomb attack.

If the United States fell victim to a dirty bomb attack, a number of conflicting regulations from different agencies could hamper attempts to clean up the site and restore order. Now that the Department of Homeland Security is coordinating efforts to develop new Federal guidance specific to such events, those conflicts could be overcome, according to the study by scientists from Argonne National Laboratory, the U.S. Department of Energy and the U.S. Department of Homeland Security.

A radiological dispersal device (RDD), or "dirty bomb," combines conventional explosives with relatively easy-to-obtain radioactive materials from industrial or medical applications. Several studies have suggested that a dirty bomb attack would not cause extensive casualties, but would be more likely to spread panic and economic disruption, leaving a potential environmental mess in its wake.

Federal, state and local officials are developing emergency response plans, but there are no common standards outlining safe contaminant levels after the cleanup of a dirty bomb, say the scientists. A variety of current radiation regulations would apply by default, but none of these is appropriate for a dirty bomb scenario, according to Deborah Elcock, an environmental policy analyst at Argonne and lead author of the paper.

Elcock and two colleagues, Gladys Klemic, of the Department of Homeland Security's Environmental Measurements Laboratory, and Anibal Taboas, of the U.S. Department of Energy, stress the need to develop a specific approach for dealing with the cleanup of a dirty bomb attack, and to have it in place before any such attack occurs.

"This paper is not intended to propose or advocate particular policies," Elcock says. "We do advocate expediting the process, ensuring public involvement and balancing existing radiation protection goals with more generally applicable societal goals."

Determining federal authority and addressing inconsistencies in regulations from various agencies could complicate and delay cleanups, Elcock says. For example, both the U.S. Environmental Protection Agency and the Nuclear Regulatory Commission have established dose-based cleanup goals for sites contaminated with radiation. The EPA advocates a personal dose limit of 15 millirems per year, and the NRC recommends 25 millirems per year. Such conflicts could lead to arguments that might undermine public confidence and delay remediation efforts, according to Elcock. And, she adds, as additional societal factors are at stake, it is likely that RDD cleanup goals may differ significantly from traditional cleanup goals.

Another issue is that the computer models designed to set maximum levels of radiation in soil are based on cleanups in rural environments, whereas a dirty bomb attack would most likely occur in a city.

"For example, it is possible that if an RDD were detonated near a hospital and the cleanup criteria were similar to those required for the cleanup of a Superfund site, the hospital probably would have to be demolished and the rubble moved from the site," the authors say. In such a case, the researchers note, "medical care could be denied to those who would otherwise have been served by that hospital."

If these issues are not brought into the open prior to an event, the consequences of an attack could be portrayed as more severe than they actually are, the authors say.

The Department of Homeland Security has formed an interagency working group, which includes representatives from eight Federal departments and agencies, to develop new guidance for cleaning up after any dirty bomb attack. The group is expected to report its findings later this year.