You are here:
Predicting wildfire particulate matter and hypothetical re-emission of radiological Cs-137 contamination incidents
Citation:
Baker, K., S. Lee, P. Lemieux, S. Hudson, B. Murphy, J. Bash, S. Koplitz, K. Nguyen, W. Hao, S. Baker, AND E. Lincoln. Predicting wildfire particulate matter and hypothetical re-emission of radiological Cs-137 contamination incidents. SCIENCE OF THE TOTAL ENVIRONMENT. Elsevier BV, AMSTERDAM, Netherlands, 795:148872, (2021). https://doi.org/10.1016/j.scitotenv.2021.148872
Impact/Purpose:
This paper describes a modeling effort based on laboratory data that attempts to describe the transport of radionuclides from a hypothetical forest fire in a radionuclide-impacted forest.
Description:
Radiological release incidents can potentially contaminate wide areas with radiological materials and decontamination efforts are typically focused on populated areas leaving radionuclides in forested areas for long periods of time. Large wildfires in contaminated forested areas have the potential to reintroduce these radionuclides into the atmosphere and cause exposure risk to first responders and downwind communities. The most notable radionuclide contaminant released from radiological incidents is radiocesium (137Cs) due to high yields and long half-life of 30.2 years. A Eulerian 3D photochemical transport model was used to estimate potential ambient impacts of 137Cs re-emission due to wildfire following hypothetical radiological release scenarios. The Community Multiscale Air Quality (CMAQ) model was applied to estimate local to regional scale 137Cs impacts for an area covering northern Colorado and southern California using 4 km sized grid cells. Emissions from a large hypothetical wildfire were introduced into the wildland-urban interface (WUI) impacted by a previous hypothetical radiological release event and particulate matter (PM) - bound cesium impacts resulting from the hypothetical wildfire were estimated for a variety of meteorological conditions to characterize downwind population exposure. While ambient concentrations tended to be highest near the fire, highest exposure (person-rems) was downwind where wind flows moved smoke to high population areas. Seasonal variations in meteorology (wind flows) can result in differential population impacts even in the same metropolitan area. Modeled post-incident ambient levels of PM2.5-bound 137Cs both near these wild fires and further downwind in nearby urban areas were well below levels that would necessitate population evacuation or warrant other protective action recommendations such as shelter-in-place. These results also suggest that decontamination efforts focused on forests not be elevated in priority solely based on potential downwind exposures due to future wildfires in the contaminated area and firefighters would not be expected to be at elevated risk from 137Cs re-emission.
URLs/Downloads:
DOI: Predicting wildfire particulate matter and hypothetical re-emission of radiological Cs-137 contamination incidents
Free access through PMC