Preliminary analysis of accidents of the Santa QuitÉRia Project: gaussian methodology for atmospheric dispersion

The Santa Quitéria Project (PSQ) is an enterprise that aims at the production of phosphate compounds as main products, and of uranium concentrates as by-products, from the minerals of the Itataia deposit. The intended area for implementation of the project is located in the municipality of Santa Quitéria, north central region of the State of Ceará. The U.S. Nuclear Regulatory Commission, lists the basic design accidents for a Uranium Processing Plant, such as the PSQ. Among all these scenarios,fire in uranium extraction cells was the one with the highest doses released. For simulation of the fire event, the atmospheric dispersion model used was the standard Gaussian plume model. The doses were calculated for two sets of meteorological conditions: stability class F, with wind velocity of 1 m/s and class D stability with wind velocity of 4.5 m/s. For PSQ, it was considered that there will be no public individual until after 2000 meters from the release point. The doses corresponding to the Occupationally exposed individuals are: 2.0E-3 mSv (class D) and 5 mSv (Class F), 300 meters away from the event. Analyzing the results, it can be concluded that there are no significant radiological consequences for the occupationally exposed individual, both in the stability class D and the F. For PSQ, it was considered that there will be no public individual until after 2000 meters from the release point. The doses, in mSv, corresponding to the individuals located near the project are: Morrinhos (1.27E-03 mSv - Class D and 3.92E-02 - Class F); Burned (1.41E-03 mSv - Class D and 4.28E-02 - Class F); Lagoa do Mato (<7.94E-04 mSv - Class D and <2.68E-02 mv - Class F). (author)