MARKETS

Using modelling to understand water flow

THE application of computer modelling to understanding what effect mining may have on water flow is becoming a tool to be used with increasing confidence, according to Winton Gale, managing director, SCT.

Staff Reporter
Using modelling to understand water flow

Gale described developments in using the approach at the recent subsidence management conference organised by The Mine Subsidence Technological Society (MSTS).

The two-dimensional model was developed for longwall caving but was applicable to model ground subsidence, overburden damage and induced hydraulic conductivity, or water flow, Gale said. Though further research and verification needs to be completed yet.

Hydraulic conductivity, or water flow, can be estimated using the modeling method. This allows a picture to be built of the impact on aquifers and water bodies. The approach aims to provide a better understanding of the fracture distributions and their impact on conductivity.

Stress distribution around longwall panels, caving and subsidence create a fracture network of bedding, shear and tension fracture planes. This fracture network can extend outside the mined panel. For instance near surface bedding planes can be mobilized as a result of large scale stress redistributions rather than induced subsidence.

Modelling can be used to provide additional information about the fracture networks around panels. This can be fed into the mine plan to evaluate the effect on aquifers and surface features.

“Modelling is viewed as a powerful tool to be used in conjunction with other approaches,” Gale said, “however ongoing monitoring and validation is an essential part of the process to ensure the ground behaviour is being simulated in a realistic manner.”

Where the approach has been applied to sites, the modeled behaviour is consistent with the monitored behaviour of aquifers and inflows.

Gale said the modeling has been shown to provide a good understanding of fracture networks created and an estimation of the conductivitiy within the overburden.

Current ACARP research has involved modeling water flow at a super critical shallow operation in the Bowen Basin and a deep single, sub critical panel in the Bulli Seam. Research is continuing to investigate ways to calculate permeability better.

TOPICS:

A growing series of reports, each focused on a key discussion point for the mining sector, brought to you by the Mining Monthly Intelligence team.

A growing series of reports, each focused on a key discussion point for the mining sector, brought to you by the Mining Monthly Intelligence team.

editions

Mining Magazine Intelligence Exploration Report 2024 (feat. Opaxe data)

A comprehensive review of exploration trends and technologies, highlighting the best intercepts and discoveries and the latest initial resource estimates.

editions

Mining Magazine Intelligence Future Fleets Report 2024

The report paints a picture of the equipment landscape and includes detailed profiles of mines that are employing these fleets

editions

Mining Magazine Intelligence Digitalisation Report 2023

An in-depth review of operations that use digitalisation technology to drive improvements across all areas of mining production

editions

Mining Magazine Intelligence Automation Report 2023

An in-depth review of operations using autonomous solutions in every region and sector, including analysis of the factors driving investment decisions