Radon problems in mining and post-mining areas in Upper Silesia region, Poland

The new basic safety standards (BSS) Directive 2013/59/Euratom [1] puts EU member states under an obligation to establish, amongst others, national radon action plans. In order to address the issue of long-term risks from radon exposures, it is important to identify areas where elevated levels of radon can be expected. One of the types of areas affected by an increased migration of radon and by the penetration of radon into buildings are areas in which industrial activity, for example, the exploitation of mineral resources, causes changes in the geological environment. The Upper Silesian Coal Basin (USCB) in Poland is one of the examples. The results of studies conducted in the past have shown that the levels of indoor concentration of radon, to a large extent, depend on the geological structure of the subsurface layers. One of the main factors influencing the migratory abilities of radon are the mining-induced changes of a rock body. We estimate that in specific radon-prone zones, the levels of radon may exceed 300 Bq/m³ in approximately 2% of the dwellings. Another problem that may appear in post-mining areas is linked to the reclamation of radioactively contaminated areas. The complex geology of the strata in USCB, the mining activity that can be observed in the region and, additionally, the discharge of radium-bearing waters into the environment are the most significant factors affecting radon potential and hazard in dwellings in this region. In this paper, problems linked to the detection of radon in the mining area of USCB are presented.