Description: Presented by: Matthew Fuller, Tierra Group International Ltd. The presentation explains in simple, layperson’s terms, what an upstream tailings dam is, and why they are susceptible to dam failures. Using recent dam failures in Brazil as precedent for the impacts associated with the upstream tailings dam construction method, the presentation explains the upstream construction methods, historical development and broad use, inherent liquefaction potential and dam failure risk, and the unfortunate consequences thereof. The presentation was originally presented at the 2019 SME MPD Conference where it received the Conference’s annual Lou Cope Award for Best Presentation.