Tailings dams are designed to meet specifications to withstand very low probability events, such as floods and earthquakes.
Dam break analysis and inundation studies are primarily used to inform the emergency preparedness and response planning and the dam classification. The dam classification is then used to inform the design specifications.
They are based on hypothetical scenarios not connected to probability of occurrence. Any imaginable cause of failure, which has a probability greater than zero, is considered.
TSFs are regulated in BC by the Ministry of Energy & Mines under the Mines Act and the Health, Safety and Reclamation Code for Mines in British Columbia (HSRC). The HRSC includes the requirement to use the Canadian Dam Association Dam Safety Guidelines.
Tailings, ground up rock (uneconomical ore after processing) plus water, are contained in the TSF. The composition of the tailings will vary depending on the composition of the rock in the surrounding environment and the process of mineral extraction used at each mine.
Tailings storage facilities are similar to conventional dams and they are subject to similar technical guidelines but serve different purposes. They are also regulated by different government agencies and under separate pieces of legislation.
A tailings storage facility (TSF) is a structure made up of (one or more dams) built for the purposes of storing the uneconomical ore (ground up rock, sand and silt) and water from the milling process.