Groundwater Dewatering is often required for excavation projects, where the impact of partial or total dewatering of the material is critical for a dry and safe working environment, as well as improving wall stabilities. Typically, this would include open and underground mining or large scale construction workings. Dewatering in the mining industry is frequently used for processing water, while out-of-mine dewatering can prevent contamination of Groundwater.
GCS provides comprehensive services in terms of feasibility evaluations as well as detailed design, management and monitoring of dewatering systems.
The success of Dewatering Studies is heavily reliant on the accurate and comprehensive quantification of aquifer characteristics through aquifer (pump) testing, packer tests or tracer tests.
A comprehensive geophysical investigation of the area is usually performed to identify preferential groundwater flow paths that will be targeted when installing the dewatering points.
Numerical groundwater flow modelling is applied to determine the optimal dewatering approach. Several options are evaluated and the optimal approach from in-pit, out-of-pit, or a combination of both is assessed and the best option identified.
Various dewatering point designs are evaluated, including vertical and inclined boreholes and horizontal drains. Well field spatial layout, borehole depths, and borehole equipment are evaluated and designed.
Dewatering lead times and depths are calculated to allow for comprehensive dewatering of the soil and rock material prior to excavation. Monitoring and continual management are also critical to the success of the dewatering operations.