Journal Article
Integrated approaches to atmospheric radionuclide dispersion for emergency management at the Brazilian nuclear complex
Alexandre Soares dos Santos; Luiz Claudio Gomes Pimentel; Corbiniano Silva; Paulo Fernando Lavalle Heilbron Filho; Itamar Frederico Souza Gonçalves; Pryscila Jesus de Sousa; Anselmo de Souza Pontes; Filipe Fernandes de Carvalho Souza; Larissa de Freitas Ramos Jacinto; Mauricio Soares da Silva; José Francisco de Oliveira Júnior; Anel Hernández Garces; Luiz Paulo de Freitas Assad; Luiz Landau
Meteorology and Atmospheric Physics · Vol. 138, Issue 5 · 2026
Abstract
This study evaluates the potential impacts of hypothetical nuclear accidents at the Almirante Álvaro Alberto Nuclear Power Plant (CNAAA), located in Angra dos Reis (RJ), in the southeastern region of Brazil, through the integration of advanced atmospheric modeling and Geographic Information Systems (GIS). The study area is characterized by complex environmental features, including mountainous terrain, remnants of the Atlantic Forest, coastal ecosystems, conservation units, and intense tourist activity. To simulate accidental release scenarios of iodine-131 (¹³¹I), the WRF/CALMET/CALPUFF modeling system was applied, incorporating high-resolution meteorological data and accounting for seasonal variability as well as topographic influences. The integration of WRF and CALMET for meteorological characterization, combined with CALPUFF dispersion simulations, provided realistic representations of the wind field, conferring confidence to the simulated dispersion patterns. A comprehensive radiological dose assessment was performed, including inhalation (short-term), external exposure to the plume (short-term), soil deposition (medium-term), and milk ingestion via the pasture → milk pathway (long-term), with comparison to the intervention levels of the IAEA (GSG-2) and CNEN (NE-1.04). The results indicate that, for children in the most impacted area, the total accumulated dose over 30 days exceeds 100 mSv, justifying the need for revision of the current Emergency Planning Zones (EPZs). The periods from November to March and from May to July present unfavorable dispersion conditions, associated with climatic instability and hydrological events. In summary, the methodological framework highlights the relevance of combining atmospheric modeling and geotechnological tools to strengthen nuclear safety and enhance emergency preparedness in coastal and densely populated regions.