REVIEW OF EXPERIENCES WITH FLOW FAILURES OF TAILINGS DAMS AND WASTE IMPOUNDMENTS

Flow failures of the mine waste impoundments have caused considerable damage to life, property and the environment over distances as great as 75 miles downstream. In the past decade there has been a dramatic increase in the size of mine waste impoundments and in the quanity of waste produced. In 1980 it was estimated that over 3 billion tons of mine waste was produced in the United States.; Case histories of flow failures of tailings dams and waste impoundments were collected and evaluated as means of developing procedures for estimating the consequences of possible tailings flow failures. In most of the cases studied, data on the post failure geometry was available. Information on the material properties, construction techniques and events leading up to failure were available in a few of the cases studied.; The study shows some liquefied tailings have appreciable values of residual strength after liquefaction, and they will come to rest at slopes of one to four degrees. A procedure is presented by which the distance liquefied tailings may flow can be estimated.