Urban critical infrastructure disruption after a radiological dispersive device event

Area of Science:

• Environmental Science
• Public Health
• Radiological Safety

Background:

• Radiological dispersal devices (RDDs) pose a significant threat to urban environments.
• Assessing the impact on critical infrastructure is crucial for emergency preparedness.
• Cesium-137 (Cs-137) is a relevant radionuclide for RDD scenarios due to its mobility.

Purpose of the Study:

• To evaluate the consequences of a hypothetical RDD detonation on urban critical infrastructure.
• To analyze the influence of local environmental factors, specifically atmospheric stability, on radiological impacts.
• To determine the extent of contamination and potential dose to the public and infrastructure.

Main Methods:

• Computer simulation using Gaussian plume modeling.
• Application of HotSpot Health Physics Codes and RESRAD-RDD software.
• Analysis of Cesium-137 (Cs-137) as the source term.
• Evaluation of atmospheric stability classes (Pasquill-Gifford classes).

Main Results:

• Atmospheric stability classes strongly influence Total Equivalent Effective Dose (TEDE) and soil contamination levels.
• Impacts on critical urban infrastructure (health facilities, public transport) correlate with contamination trends.
• Proportional ratio analysis showed calculated contamination values relative to RESRAD-RDD reference limits.

Conclusions:

• Simulated RDD impacts highlight the critical role of atmospheric conditions in radiological events.
• Environmental factors significantly dictate the severity of contamination and infrastructure disruption.
• The study provides valuable data for decision-making in the initial response phase of RDD incidents.