“In order to prepare for potential attacks, DHS held a Federal interagency ‘‘dirty bomb’’ exercise as part of the Top Officials–2 Exercise (TOPOFF–2) in Seattle, Washington, May 12–16, 2003. The exercise brought to light a number of issues in Federal radiological emergency response and recovery. One of the most important issues raised was how long-term site restoration and cleanup would be accomplished following an act of radiological terrorism”. (DHS, Application of Protective Action Guides for Radiological Dispersal Device (RDD) and Improvised Nuclear Device (IND) Incidents; Notice, Part II., Federal Register, Vol. 71, No. 1, January 3, 2006, p. 174)