Raw material samples of coal used by the main power plants in Brazil (RS; SQ PR) were evaluated. Radiological relevant radionuclides of the natural series, such as (238)U, (228)Ra, (226)Ra, (210)Pb and (40)K were analyzed by direct gamma spectrometry. The results showed that the uranium concentration in coal from (PR) was at least three times higher than concentration found in other coal samples in Brazil (RS and SC). In spite of the high uranium concentration in the PR coal, the small (10 MW(e)) local power plant currently operating in (PR) produced low amount of ashes, however more detailed studies should be done for the new power plant (140 MW(e)) in project. (c) 2006 Elsevier Ltd. All rights reserved.