Caserones — Option of Tailings Classifying to Improve Water Reclamation

Abstract

One of the areas with the most mining projects in Chile is located in the Region III. This region lies in the south end of the Atacama Desert, one of the most arid areas in the world. Besides mining, this area has a significant agricultural activity (mostly fruit related) in one of the two main valleys, which implies a strong competition for the scarce water. The Caserones project is located in the Andes mountains at an elevation of 4,000 m a.s.l. on a creek — dry most of time — tributary to the river Ramadillas, which flows into the river Copiapo. The topography of the plant area does not create favourable conditions for a tailings impoundment with the exception of the river Ramadillas valley, which implies intercepting the river and designing diversion works. The interception of permanent water courses encounters strong opposition from the authorities and the dams construction in natural water courses has been questioned in the past by the community. As a consequenc, several options oriented at designing a tailings deposition scheme were analysed that would not affect the water natural course and simultaneously would reduce the water losses to maximise water reclamation at an appropriate cost to the project. This paper presents the methodology applied to design a tailings deposition scheme that would resolve the field limitations and maximise the water reclamation throughout operations. The paper provides a description of the solution adopted and, finally, the application of this solution to other topographical conditions is analysed.