Lined Tailings Facilities - Consequential Risks Require Better Understanding

Lined Tailings Facilities - Consequential Risks Require Better Understanding

Publication: Mining Review Africa
Issue: October 2018

The mining industry in South Africa – which extends back more than a century – is grappling with historical legacies that have been put under the spotlight as the world becomes more environmentally conscious and responsible. Tailings management in particular, an area neglected in the past, is now a priority. While lining have become the preferred option to reduce possible environmental impact of tailings material they pose their own set of risks which urgently need to be monitored and addressed, Knight Piésold technical director for mining Andrew Copeland tells Laura Cornish.

Up until a few years ago, the mining industry in South Africa took a reactive approach to environmental impacts caused by mining activities. Unfortunately, tailings-related impacts are severe – and can result in loss of life, long-term damage to the environment and ground water pollution.

“The combination of legislation covered by the National Environmental Management: Waste Act, 2008, and Government Notice 332, May 2014 in which residue deposits were deemed as a waste unless de-classified or exempted by the minister, has seen the mining industry’s determination to make amends by complying. Together with government, consultants such as ourselves are working closely with the sector to improve our environmental image,” Copeland starts.

The mines have subsequently turned primarily to linings as a means to ensure seepage from tailings deposits does not come into contact with the natural environment. The government has also shown favour for this route as it considers it a proactive and trusted mechanism which guarantees protection of the environment.

“It is commendable that our industry is embracing the need to reduce its impact on the environment and we are undoubtedly heading in the right direction but few are aware that the solution we are now deploying has its own potential risks,” Copeland reveals.

The incorporation of linings for example is not a finite solution. Like most plastic-based products, they degrade over time (20–100 years possibly, depending on the quality of the lining and the material it houses) and will leak. This means they cannot be considered a long-term option on their own, and may only function well during the operational life of the tailings facility.

But there is a far greater risk at play, Copeland highlights. “The incorporation of a lining, be it traditional synthetic material the clean-up), there is the cost of having to prematurely build new facilities, an equally disastrous reality for the industry. “Considering that South Africa’s lined tailings facilities are <5 years in age, we are in a period of beginning to understand whether such designs are sustainable and if/when we reach the crossroad of having to build new tailings facilities to replace unsafe ones.”

 

Download the full article.

Download

Recent Insights

June 2024
Estimating Shear Stress within a Clay Foundation Using the Burgers-Creep Model
May 2024
Knight Piésold: Ensuring African Excellence in the DRC
May 2024
Wild Coast N2 Highway Project Taking Shape
April 2024
Risk Mitigation through Design Optimization Utilizing Seasonal Effects under Arctic Conditions at the Amaruq Mine
April 2024
Synthetic Rock Mass Modeling of Progressive Unravelling and Overall Slope Stability Using the Discrete Element Method
April 2024
Operational Slope Stability Risk Management for Large Open Pits at the Mount Milligan Mine – A Case Study
April 2024
Risk and Informed Approach to TSF Design and Operation
February 2024
Empowerment and Resilience
January 2024
Balancing Act: Water Usage Management Vital for a Sustainable Future
January 2024
A Difficult Balance Between Engineering, Environmental, Social and Economic Aspects
November 2023
Knight Piésold Commences with the ESIA for Haib Copper
November 2023
Insights from the Compilation and Critical Assessment of Breach and Runout Characteristics from Historical Tailings Dam Failures: Implications for Numerical Modelling
November 2023
Earthquake-induced Deformation Analysis of a TSF Undergoing Tailings Reprocessing
November 2023
Case Study: Approach to Determining the Risk Mitigation Priority of a Historic TSF in North America
October 2023
Data Management and Insights for Effective Tailings Storage Facility Management
October 2023
The Role of Sensitivity Analysis in Selecting Dam Breach Parameters
October 2023
Influence of Increased Confining Stress on Undrained Behavior of Tailings: A Case History at the Candelaria Mine
October 2023
The Re-use of Existing Bituminous Stabilised Materials for the Rehabilitation of National Route 7 - Case Study
September 2023
Transición energética para gerentes de mina
August 2023
Interview: Guillermo Barreda, Gerente General, Knight Piésold Perú