Methodology Used in the RadiologicalAssessment of a Coal-Fired Power Plant

摘要

A radiological assessment of the workers and the public potentially affected by theoperation of the Teruel Coal-fired Power Plant (the UPT Teruel), was performed under realisticassumptions. This assessment is part of a wider study to characterize the potential radiologicalimpact of Naturally Occurring Radioactive Materials (NORM), in which our team, integrated byUniversity of Extremadura and CIEMAT, is carrying out the study on coal-fired power plantssponsored by the Spanish Nuclear Safety Council (CSN). The study comprises the four biggestcoal-fired power plants in Spain. Taking into account the working conditions and the plantspecifications, six groups of workers were defined, established considering the 17 working tasksthat could be of any importance for this assessment. For the public, considering that the area isbarely inhabited, two different recreational scenarios were defined. Therefore, in-plant and outsidemeasurements, needed for the assessment of each scenario, were carried out. Where experimentaldata were not available or measurements ranged within the natural background radiation values,modelling has been used. Every measured or estimated activity concentration in coal and otherused materials or in the by-products generated in the power plant, for every radionuclide in thenatural chains of ~(238)U,~(232)Thand ~(40)K,were below 0.32 Bq g~(-1).Those values are under the 0.5 Bq g-1 reference value for exemption and clearance of ~(238)U,~(232)Thand ~(226)Raand the 5 Bq g~(-1)for ~(40)Krecommended in Europe. In the dose evaluations for six groups of workers, a maximum of 21 μSva~(-1)was obtained (mainly due to the inhalation of resuspended particles). For both considered scenarios for the public, all the evaluated doses were below 4.3 μSv a~(-1). These results areconsidered negligible from a radiological point of view. In this work the models and assumptionsused for the evaluation of workers and public doses, the assessment, as well as the most relevantexperimental results and conclusions are presented.