Management of Sulfide-Bearing Waste, a Challenge for the Mining Industry

Björn Öhlander,Terrence Chatwin,Lena Alakangas

doi:10.3390/min2010001

Björn Öhlander, Terrence Chatwin + Show 1 more

Open Access

https://doi.org/10.3390/min2010001

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Journal: Minerals	Publication Date: Feb 8, 2012
Citations: 24	License type: CC BY 3.0

Affiliation: Luleå University of Technology

Abstract

Oxidation of iron sulfides in waste rock dumps and tailings deposits may result in formation of acid rock drainage (ARD), which often is a challenging problem at mine sites. Therefore, integrating an ARD management plan into the actual mine operations in the early phases of exploration, continuing through the mine life until final closure might be successful and decrease the environmental impact. A thorough characterization of ore and waste should be performed at an early stage. A detailed knowledge of mineralogical composition, chemical composition and physical properties such as grain size, porosity and hydraulic conductivity of the different waste types is necessary for reliable predictions of ARD formation and efficiency of mitigation measures. Different approaches to prevent and mitigate ARD are discussed. Another key element of successfully planning to prevent ARD and to close a mining operation sustainably is to engage the mine stakeholders (regulators, community and government leaders, non-governmental organization (NGOs) and lenders) in helping develop and implement the ARD management plan.

Highlights

There has been a tremendous development of reducing the environmental footprint of mining the last several decades, but mining operations may still have detrimental effects on soil, water and biota.Mining operations generally require large areas of land, and associated conflicts arise that are primarily related to competing land uses
The primary approach to the prevention and mitigation of acid rock drainage (ARD) is to minimize the supply of the primary reactants for sulfide oxidation, and/or maximize the amount and availability of acid-neutralizing reactants
In the case of water minimization, does it control the formation of ARD, but it limits ARD and leached metals from being transported from the mine waste

Summary

Introduction

There has been a tremendous development of reducing the environmental footprint of mining the last several decades, but mining operations may still have detrimental effects on soil, water and biota. The major potential long-term environmental effect of mining is formation of acid rock drainage (ARD) in sulfide-bearing mine waste, which can last for hundreds or even thousands of years (e.g., [1,2]). The oxidation rate depends on several factors including oxygen availability, temperature, pH, bacterial activity and surface area of pyrite grains [6,7,8] This acidification enhances the mobility of heavy metals and other elements occurring in the mining wastes The costs carried by many mining companies to cover current liabilities are a clear indication of the gravity of the problem To address these problems the International Network for Acid Prevention (INAP) has developed the GARD Guide, an internet-based best practices guide to prevent and mitigate the formation of acid, neutral and saline drainages from mining operations [2]. We will describe proven practices that prevent and mitigate ARD in mining and other excavations, mainly based on the GARD Guide [2], and the Swedish MiMi-programme [1]

Results and Discussion—Prevention and Mitigation of ARD

ARD Prevention and Mitigation Best Practices

Engaging Stakeholders

Historical Mine Waste

Conclusions

20. Best Practice Guideline—H2