The Equity Silver Mine operated between 1980 and 1994, producing silver, gold, and copper from three open pits and a small underground operation. Mine components include a flooded tailings impoundment constructed from till and waste and quarried rock. This paper describes the initial design and subsequent performance of the flooded tailings impoundment. Materials disposed in the tailings impoundment include tailings, lime treatment sludge, cyanide and acidic drainage.