Read our new report, researched and written by Steven Emerman.
The Riotinto Mine is an open-pit copper mine operated by Atalaya Mining in the province of Huelva, Autonomous Community of Andalusia, southern Spain. The mine currently processes 9.5 million metric tons of ore per year with plans to expand to 15 million metric tons per year (Atalaya Mining, 2019a). Given that the grade of the ore is 0.41% copper and that the mine produces a copper concentrate with 22 percent copper (Ore Reserves Engineering, 2018), each year of current production results in over 9.3 million metric tons of waste. These waste materials that remain after processing of the ore are called mine tailings and are stored in the Cobre and Aguzadera tailings reservoirs (also called tailings ponds or tailings storage facilities or tailings management facilities. Another type of waste (called mine waste rock) is the rock that must be removed to arrive at the ore body. The storage of mine waste rock will not be discussed in this report. The Cobre and Aguzadera reservoirs are each confined by a tailings dam, although the two reservoirs also share a common dam wall. Excess water from the tailings reservoirs is pumped behind a third dam into the Gossan reservoir. Since the Cobre reservoir is upstream from the Aguzadera reservoir and the Gossan reservoir is upstream from both tailings reservoirs, the three dams could fail in a chain reaction.