Reclamation of Mine-impacted Land for Ecosystem Recovery

Nimisha Tripathi, Raj S. Singh, Colin D. Hills

• Publisher: Wiley-Blackwell
• Year: 2016
• Print ISBN: 9781119057901
• eBook ISBN: 9781119057932
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Civil Engineering
• Index: Technology & Engineering

Mining activities significantly impact the environment; they generate huge quantities of spoil, promote deforestation and the loss of agricultural production, as well as releasing contaminants that result in the loss of valuable soil resources. These negative impacts are now being recognized and this book shows how corrective action can be taken.

The introduction of sustainable mining requires mitigation strategies that start during the mine planning stage and extend to after mineral extraction has ceased, and post-closure activities are being executed.

Reclamation of Mine-impacted Land for Ecosystem Recovery covers: methods of rejuvenation of mine wasteland including different practices of physical, chemical and ecological engineering methods; benefits of rejuvenation: stabilization of land surfaces; pollution control; aesthetic improvement; general amenity; plant productivity; and carbon sequestration as well as restoring biodiversity and ecosystem function; best management practices and feasible solutions to the impacts of mining which will reduce the pollution load by reducing the discharge rate and the pollutant concentration; reduce erosion and sedimentation problems, and result in improved abandoned mine lands; and ecosystem development.

The authors explain how mining impacts on soil properties and how soil carbon reserves/soil fertility can be restored when mining has ceased. Restoration involves a coordinated approach that recognizes the importance of key soil properties to enable re-vegetation to take place rapidly and ecosystems to be established in a low cost and sustainable way. 

This book's unique combination of the methods for reclamation technologies with policies and best practice worldwide will provide the background and the guidance needed by scientists, researchers and engineers engaged in land reclamation, as well as by industry managers.

1
Introduction

1.1 Background and purpose

Since Palaeolithic times (ca. 450 000 years ago), mining has been an integral part of the human existence (Hartman, 1987). Mining is fundamental to technological development and there is evidence of subsurface mining dating back to 15 000 BC (Kennedy, 1990).

Throughout the world, the most common form of mineral extraction is surface or open-pit mining. Minerals with a low stripping ratio generate large amounts of overburden or spoil, which are discarded on adjacent land surface.

The discarded overburden is disposed of in surface dumps, which significantly impact upon both flora and fauna. Spoil dumps occupy large areas of productive land and contaminate surface and subsurface water resources, upon impacting ecological pools and biological processes (Tripathi et al., 2012). The loss of key components of an ecosystem directly results in land degradation.

Surface mining disrupts the environment by disturbing the landscape, despoiling agricultural land and through deforestation. The consequence of mining is a loss of plant biomass and land productivity. The environmental impacts caused by mining, based on Richards (2002), are:

• Ecosystem disturbance and degradation
• Habitat destruction
• Adverse chemical impacts (from improperly treated wastes); and
• Loss of soil-bound carbon (to the atmosphere)

The management of mine spoil/degraded land is a major issue throughout the world. The ecological and environmental impacts of mining warrant a corrective action supported by appropriate post-closure management strategies. By managing environmental impacts, the long-term viability of mining operations can be secured.

The practice of ecological restoration of disturbed and degraded land is a primary action in ecosystem recovery. This is achieved by ensuring a nutrient cycling is re-established, which in turn fosters increasing biodiversity.

The introduction of a progressive post-mining plan, which considers the ecological condition of the land (to be mined) and the suitability of native plants for reclamation activities is an important step as this:

• Minimizes the overall impact of mining at a site
• Ensures an appropriate post-mining closure design is implemented
• Reduces overall cost
• Enhances environmental protection and restoration of soil-based carbon
• Reduces the time frame for completing the reclamation strategy

Post-closure reclamation actions can be implemented immediately after the cessation of mining and should utilize the best available technology options available.

Thus, by using appropriate management strategies, such as mulches and organic matter-based additions, re-vegetation can be effectively carried out post mine closure. Reclamation will re-establish the soil carbon reserve lost during mining that is essential for the correct functioning of vegetation. The reintroduction of soil organic matter is achieved via the removal of CO₂ from the atmosphere into root mass and leaf litter. The growth of biomass reduces the amount of CO₂ in the atmosphere, and...

Table of contents

• Cover
• Title Page
• Table of Contents
• Preface
• About the authors
• Acknowledgements
• 1 Introduction
• 2 Mining and ecological degradation
• 3 Regulation of reclamation
• 4 Development processes in disturbed ecosystems
• 5 Benefits of reclamation
• 6 Best practice reclamation of mine spoil
• 7 Carbon uptake into mine spoil in dry tropical ecosystems
• References
• Index
• End User License Agreement