The framework uses a four-lines-of-defense model: • First line of defense: A site team that actively manages the facilities and includes the General Manager; a Responsible Tailings Facility Engineer/ Person (RTFE/P), who is accountable for the integrity of the site’s TSFs and oversees their design, construction and monitoring; and a dedicated Engineer of Record (EoR), who provides technical expertise and assurance that the TSF is safely designed, constructed and operated.