The problem of obtaining environmentally safe materials is particularly relevant when using waste that concentrates natural radionuclides which are dangerous to human health and the environment.
Such radionuclide concentrators include waste from the coal mining and heat power industries. The aim of the work is to determine the radionuclide composition of fractions of coal mining waste and fuel ash-slag and their compliance with the radiation safety standards of the Russian Federation and international radiological indicators. Natural radionuclides 226Ra, 232Th, and 40K were found in the composition of fuel ash-slags and the slag from the coal mining. The content of radionuclides varies by fraction of the waste. The main contribution to the effective specific activity of the waste is made by 226Ra and 232Th.
The largest variation in specific activities by fractions of fuel ash and burnt coal is characteristic of 226Ra. All the investigated wastes belong to the I class of radiation hazard (Cef < 370 Bq/kg) and can be used in construction without limitation. According to the international radiological indicators, the value of the activity utilization index is exceeded for almost all the investigated wastes. The gamma radiation of the burnt dump rocks of the Olkhovatskaya mine (fraction less than 0.63 mm) exceeds the recommended limits in terms of the values of the internal hazard index and gamma index. The values of radium equivalent activity of 226Ra and the alpha index indicate that the investigated ash-slag and dump rock do not pose a danger of increased emanation of radon and daughter products of its decay into the room air. The concentration of radon entering the room air does not exceed 200 Bq/m3 . The air-absorbed dose rate for the investigated wastes and the annual effective equivalent dose are higher than the world average, respectively: 58 nGy/h and 0.07 mSv, but lower than the value recommended by the IAEA for the population, 1 mSv/y. The excess lifetime carcinogenic risk is higher than the global average: 0.29·10–3 , but below the limit of 0.05 established by the International Commission on Radiation Protection