Comprehensive review of the effectiveness of mine rock management and decommissioning practices

Decommissioning practices for waste rock are based on the characteristics of the waste rock, the associated 'environmental drivers' for COC release, the nature and magnitude of transport pathways, and exposure and risk to human or ecosystems as a function of time. Safety assessments for decommissioning practices are used to estimate release rates from the waste rock, determine if any potentially significant quantities of COCs are anticipated, and to determine if or how the loadings may be modified before discharge to the receiver. In general, the largest uncertainties with safety assessments are associated with the estimates of release rates. Much of the effort related to mine rock safety assessments have focused on methods and procedures to determine mine rock reactivity, and the potential to release metals and other chemicals and radionuclides of concern, including acid. This paper represents a summary of a review (Stantec, 2003) that was initiated by the Canadian Nuclear Safety Commission on the assessment and effectiveness of waste rock management and decommissioning practices. (author)