Design criteria for upstream raised tailings storage facilities

For more than 100 years upstreaming has been the dominant raising method for tailings storage facilities in Southern Africa. However, there is a growing view worldwide that upstreaming is inherently less safe than centreline or downstream raising of tailings storage facilities. Considering that more than 90% of the 250 plus operational tailings storing facilities in Southern Africa are upstream raised and cannot economically be converted to, or replaced by, downstream raised facilities, the arguments for and against upstreaming were examined in this study. It was found that no compelling reason exists to ban upstreaming in Southern Africa, provided that failure mechanisms are thoroughly considered to prevent serious design omissions. The ALARP (as low as reasonably practicable) approach is introduced as a practical method to deal with the risk of failure, and its hierarchical application is illustrated.