A Case Study of the Radon Hazard at the Boundary of a Coal Minefield

The main purpose of this study is to assess the radon hazard in areas near the boundary of a coal mine. Our assessment included an analysis of the soil’s radon volume activity (VAR) and radon flux density (RFD), as well as their spatial characteristics and correlations with other factors. The soil VAR varies in the range from 3477.7 to 17,520 Bq/m3 (mean value 9786.9 ± 474.9 Bq/m3), and RFD from 10 to 160 mBq·m−2·s−1 with a mean value of 59.76 ± 2.45 mBq·m−2·s−1. The RFD parameter is spatially clustered (p ≤ 0.01). No significant differences between RFD and soil VAR were found, both inside and outside the minefield areas (p ≥ 0.05). However, we suggest considering the entire studied space of the minefield boundaries and surroundings to be radon-hazardous. This contributes to the understanding of the radon hazard of coal mines for ground structures both in the mine area and in its surroundings.