Investigating Radon Exhalation Parallels between waste-rock dumps and mountain screes

Abstract:

Ventilation is a well-established method for mitigating high radon concentrations indoors. However, its effectiveness relies on the assumption of naturally low atmospheric radon levels. Yet, there are instances where elevated radon concentrations can challenge this assumption. Our investigation focuses on a specific scenario: a specific waste-rock dump near Pribram (Czechia) contains residual uranium ore and is a notable radon source, exhibiting pronounced seasonal and diurnal fluctuations caused by changing airflow regimes within the dump. Particularly during summer nights, the dump releases air with an increased radon concentration, which travels over considerable distances while preserving a high radon concentration (more than 10 000 Bq/m3 detected 100 m away from the foot of the slope). This behaviour finds a parallel in the dynamics of airflow within naturally occurring mountain screes. By studying these natural scree airflows, we can better understand the mechanisms driving the observed radon emission patterns. This analysis enhances our understanding of radon exhalation from waste-rock dumps, helping us to describe the waste-rock dump as a radon source and further aiding in the study of radon behaviour in the vicinity of similar locations.