Spatial and seasonal variation of radionuclides in soils and waters near a coal-fired power plant of Northern Greece: environmental dose assessment

The determination of the radionuclides of U- and Th-series as well as of K-40 and Cs-137 in soils and waters in a lignite mining area was performed. The measurements in the soils were undertaken by gamma-ray spectrometry while the concentrations of U-234 and U-238 in waters and the isotopic ratio U-234/U-238 were determined by alpha-ray spectrometry. Slight seasonal variation of the radioactivity was observed with high values in summer and low in winter. The estimated annual radiation dose from soil was lower than the worldwide average whereas in the case of water only one location showed increment in the internal radiation about 18 % of the worldwide average.