Radiation properties of industrial waste

The problem of obtaining environmentally safe materials is especially important when using waste products that concentrate in themselves natural radionuclides (NR), which pose a danger to human health and the environment. Similar concentrators of NR include waste from the coal mining and power engineering industries. The aim of the work was to determine the radionuclide composition of fractions of coal mining waste and fuel ash-slag and their compliance with the radiation safety standards of Ukraine and international radiological indicators. NR: ²²⁶Ra, ²³²Th, and ⁴⁰K were found in the composition of fuel ash-slags and slag from coal mining. The content of radionuclides varies by fraction of the waste. The main contribution to the value of the effective specific activity  of waste is made by ²²⁶Ra and ²³²Th. The largest variation in specific activities by fractions of fuel ash-slags and dump rock of coal mining is characteristic of ²²⁶Ra. All investigated wastes belong to the I class of radiation hazard (Bq/kg) and can be used in construction without restrictions. According to international radiological indicators, the value of the activity utilization index is exceeded for almost all of the investigated wastes. The gamma radiation of the burnt dump rocks of the Olkhovatskaya mine (fraction <0.63 mm) exceeds the recommended limits in terms of the value of the internal hazard index and gamma index. The values of radium equivalent activity Ra_eq 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 dose equivalent 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 cancer risk is higher than the world average value of 0.29^.10^–3, but below the 0.05 limit established by the ICRP.