Authors: K. Viveros, P.A. Guerra, S. Gonzalez
Procemin 2009, Santiago, Chile
Abstract
Water scarcity is one of the main challenges that the mining industry in Northern Chile has to address whether for an existing mine, a mine expansion, or a new mine. Most of the mining operations in Northern Chile are located in a desert climate, regions that lack moisture, especially due to insufficient rainfall. These regions are typically located at elevations of 600 meters or more above sea level, where the main local water supply is from groundwater sources which are limited in water quantity and quality. The quality of the groundwater is typically brackish and may require treatment. Most of the mining activities can outlast the local water reserves, and therefore many projects have considered, and continue to develop, the use of seawater or desalinated water to supply their operations.
Water supply projects in Chile face other engineering challenges. A number of significant issues must be considered in order to provide the best overall solution, such as local geography, community relations, environmental impacts, and energy requirements, for the implementation of large seawater treatment and conveyance systems. These issues limit the number of alternative designs that can be considered for these types of coastal infrastructure projects. In order to achieve significant savings in CAPEX and OPEX costs, the design of these water supply projects must also involve the development of an accurate water balance so that the seawater treatment plants, pipelines, and pumping stations, are not over (or under) designed. Project logistics must also reflect progressive change in the water demand and may need to consider modular, expandable design.
The high energy consumption of conveyance and the availability of an power sources represent a significant challenge. Previous design experience is fundamental in developing and delivering successful water supply projects, considering the large number of issues, various aspects and interactions encountered during design that must be taken into account.
The objective of this paper is to present an approach towards these types of projects, identifying key issues that will impact the feasibility and costs of the project. A planning strategy has been developed, orientated to optimizing the design of the water supply project, which is based on Hatch work experience of water supply projects in Chile.
