Página 325 - irpa

325 ST 4.2 – Emergencias radiológicas y nucleares
SCENARIOS FOR THE ASSESSMENT OF URBAN EXPOSURES
AFTER RADIOACTIVE CONTAMINATION
Neves Gomes da Silva, Diogo1*; Rua Rodriguez Rochedo, Elaine 2;
Remy Davée Guimarães, Jean1
1 Universidade Federal do Rio de Janeiro (UFRJ). Brasil.
2 Instituto de Radioproteção e Dosimetria (IRD/CNEN). Brasil.
* Responsible author, email: dneves@biof.ufrj.br
Accidents involving radioactive material are not frequent but may include releases of
radionuclides to the air, land or waterways. These releases are usually uncontrollable and may
lead to doses in the public in excess of the reference levels established by regulations defined
by the national regulatory agencies of each country. Although they had occurred sporadically
since the last century, it was observed that, after the emergency phase, the public concern is
enhanced when they feel that there is an unpreparedness of authorities responsible for
remediation actions, due to the lack of definition of strategies to be adopted in the long term
after such events. The aim of this work is to describe reference urban scenarios, considering the
characteristics observed in residential and free access areas of urban centers. These scenarios
were developed based on the counties surrounding the Brazilian nuclear power plant.
Considering the counties that within 50 km from the nuclear power plant, nine belong to the
state of Rio de Janeiro and seven belong to São Paulo state; the highest population densities
were observed in five counties of Rio de Janeiro. Based on the different types of residences and
outdoor areas observed in these 16 counties, six reference scenarios for urban areas were
developed including areas comprised by four types of residential houses (with low, medium and
high shielding building material and houses in a row), apartments in buildings, and park areas
with lawn and trees. The characteristics of each of these scenarios were raised through Google
Earth images considering 1 km2 of different locations comprised by each type of area defined. In
a next step, the information obtained in each scenario shall be used in computer simulations to
characterize the effects and consequences on public exposure of the application of
decontamination procedures.