| Summary: |
Radioactivity dispersed in the environment result not only from nuclear fuel cycle activities but also from other several technological activities. The most relevant non-nuclear industry, in what concerns to radioactive elements emissions, are phosphates industry, ceramic industry and energy production activities, in particular thermal coal power plants. Over the past few decades there has been some discussion about the elevated natural background radiation in the area near coal-fired power plants. Since the publication of the article "Radiological Impact of Airborne Effluents of Coal and Nuclear
Plants" [1] it is well known that background elevation originated from coal-fired power plants is greatly higher than the elevation originated by nuclear power plants, due to high uranium and thorium content present in coal. Their radioactive decay products are also released such as radium, radon, polonium, bismuth and lead. Also there is a significant release of 40K. Since radioactive elements from coal power plants emissions are not obligatory measure parameters, there is no measure data or concentration estimative for the radioactive elements released. Consequently, predicting dispersion and mobility of these elements in the environment, after their release, is based on limited data and the radiological impact from the exposure to these radioactive elements is unknown.
The main objectives of this research project is to assess the dispersion of radioactive elements present in coal power plant emissions to assess the radiological risk induced by natural background elevation in the its vicinity. This proposal will focus on the development of a specific dispersion environmental model to this particular situation which is highly dependent of local meteorological conditions in which the thermal power plant is implemented. In addition, beside radioactive elements, a high quantity of other elements is released such as Al, Fe e S, and metals such as As, Cd, Cr, Pb, Zn, Hg an  |
Summary
Radioactivity dispersed in the environment result not only from nuclear fuel cycle activities but also from other several technological activities. The most relevant non-nuclear industry, in what concerns to radioactive elements emissions, are phosphates industry, ceramic industry and energy production activities, in particular thermal coal power plants. Over the past few decades there has been some discussion about the elevated natural background radiation in the area near coal-fired power plants. Since the publication of the article "Radiological Impact of Airborne Effluents of Coal and Nuclear
Plants" [1] it is well known that background elevation originated from coal-fired power plants is greatly higher than the elevation originated by nuclear power plants, due to high uranium and thorium content present in coal. Their radioactive decay products are also released such as radium, radon, polonium, bismuth and lead. Also there is a significant release of 40K. Since radioactive elements from coal power plants emissions are not obligatory measure parameters, there is no measure data or concentration estimative for the radioactive elements released. Consequently, predicting dispersion and mobility of these elements in the environment, after their release, is based on limited data and the radiological impact from the exposure to these radioactive elements is unknown.
The main objectives of this research project is to assess the dispersion of radioactive elements present in coal power plant emissions to assess the radiological risk induced by natural background elevation in the its vicinity. This proposal will focus on the development of a specific dispersion environmental model to this particular situation which is highly dependent of local meteorological conditions in which the thermal power plant is implemented. In addition, beside radioactive elements, a high quantity of other elements is released such as Al, Fe e S, and metals such as As, Cd, Cr, Pb, Zn, Hg and V. We intend to assess the resulting risk from exposure to these materials released and accumulated in the vicinity of the Sines power plant.
The final purpose is to apply the developed model and calibrate the model to the Sines Thermal Power Plant. First, collection and compilation of the local meteorological characteristics (wind pattern, rainfall and temperature) will be
developed. Second, It will be implemented a continuous monitoring system for aerosols or airborne particles for one year period.
After this period time, airborne concentrations will be assessed per area unit and per time unit. Simultaneously, during this period radioactive element sampling will be done as well as metals assessment in the influence area.
Heavy metals measurements will be performed with a portable analytical X-Ray dispersive energy fluorescence spectrometer, in two campaigns (end of the summer and beginning of the spring) in a grid sampling dependent on the influence area defined.
Radionuclides measurements at locations of the coal-fired power plant will be conducted also in the same campaign: one in the end of the summer (September) and the other one at the spring (March) with a portable radionuclide identifier, by gamma radiations measurement, with energy discrimination. The sampling point won't be necessary coincident with the metals sampling points.
Collected data from spatial distribution will be analyzed by statistical and geostatistic techniques with the integration of the data in a Geographical information system; it is our intention to develop a phenomenological model for metal and radioactive elements release and dispersion in the context of background enhance to assess inhalation and ingestion dose. Finally, this information will be support to perform the respective risk assessment represented by thematic risk mapping. |