Natural radioactivity in waters and sediments from a Spanish mining river

In this work we present results of a study concerning the distribution and behaviour of several natural radionuclides (U, Th-isotopes, Po-210 and gamm a-emitters) in a mining river located in the southwest of Spain. Enhancemen ts of U concentrations relative to other analysed isotopes within the U ser ies have been observed, being due to co-precipitation of U with heavy metal s in accord with increases in pH along the river. The U excess can be trace d to uranium dissolution in waters that have been used as a part of a miner al treatment process within the mine, the water subsequently being released into the river, (C) 2001 Elsevier Science Ltd. All rights reserved.