Among industrial wastes containing radioactive elements, excluding those generated by nuclear technology, of particular concern are fly ashes originating from coal-fired thermalelectric power stations, and phosphogypsum. Both wastes are produced in amounts of the order of a few million tons in a year, thus posing serious problems with their utilization and/or safe disposal. Lanfilling of these materials within large urban areas may be hazardous to residents by way of ingestion, consumption of foods from contaminated areas and drinking water containing toxic elements.
This contribution presents results of investigations on the behaviour of uranium, radium and polonium in fly ash under the influence of a variety of extractants as well as the impact of a phosphogypsum dump, located at Wislinka, on the environment. It has been found that both alkaline and neutral solutions leach out less than one per cent of the nuclides, whereas under the action of acid solutions (0.1-1 M HCl), as much as 12% of radium and 31% of uranium are released. Under the influence of atmospheric precipitation, phosphogypsum has been found to produce solutions of mass radioactivities ranging from 0.3 to 1.8 Bq/l. The Ra-226 levels in groundwater supplies surrounding the dump site are by 2-3 orders of magnitude lower and do not reach a limiting value of 0.1 Bq/l recommended by the WHO guidelines for drinking water.