Decommissioned Uranium Mines in Uzbekistan - Impact on Environment and Health

Uzbekistan (as well as some other Central Asian Republics) was in the past and is in the present an important producer of uranium. After 1996 only ISL uranium mines remained operational. All conventional 'hard rock' mines were decommissioned leaving behind sizable volumes of mine wastes and mill tailings and contaminated sites. For the preparation of the remediation of these legacy wastes and sites it is very important to first create a reliable data base on which the preparation of the remedial strategy could be based. The problem of the legacy sites is complicated by the fact that the former uranium mining sites are located in the mountainous part of the country and close to rivers that are used by the local population as a source of water. The situation is further complicated by the geo-morphology of the sites, which makes the mine wastes prone to be dislocated by mudflows. To obtain a first appraisal of the radiological situation at the uranium mining legacy sites, the Uzbekistan Academy of Sciences went on investigating two sites: Yangiabad and Charkesar. A great number of measurements of the gamma radiation, radon concentration and analysis of radionuclides content in various media on the sites were carried out. The effective radiation doses due to exposure to radon were also determined. The radionuclide content in the foodstuff produced on the sites and in the vicinity was analysed and the exposure via ingestion appraised. The collected data and information provides important background information for prioritization of the remedial actions and for development of a more focused investigation program for the sites. (author)