Environmental Monitoring Data Review of a Uranium Ore Processing Facility in Argentina

A former uranium ore processing facility in Argentina is currently undergoing the last steps of environmental restoration. The operator has been performing post-closure environmental monitoring, while the Argentine Nuclear Regulatory Authority (ARN) has been carrying out its own independent radiological environmental monitoring for verification purposes. A detailed revision of ARN´s monitoring plan for uranium mining and milling facilities has been undergoing since 2013, starting with this particular site. Results obtained from long-time sampling locations (some of them currently unused) have created datasets with outliers and below detection-limit values which need to be analysed in order to decide if these sampling-points are useful, or new ones should be proposed. In this paper, the methodology and statistical tests used for analysing and comparing these datasets is presented, and conclusions are drawn for keeping or discarding sampling-points in future monitoring plans. (author)