Environmental Impacts of Mining

Monitoring, Restoration, and Control, Second Edition

Mritunjoy Sengupta

• Publisher: CRC Press
• Year: 2021
• ISBN:
  9781000374506
• Edition: 2
• Topic: Scienze biologiche
• Subtopic: Scienze ambientali

This second edition examines the problems facing the mining industry, and offers practical case studies, as well as new solutions for environmental restoration and remediation. New topics include bioremediation technology, mountaintop surface coal mining, reclamation procedures, environmental impacts of gold mining, mining in different countries worldwide, and the resulting environmental problems. The book is considered a "must have" book for environmental engineers and professionals in the mining industry, geologists, hydrologists, hazardous waste professionals, and academics.

1 Mining and the Environment

1.1 Introduction

Mining operations have been seen by environmentalists and conservationists alike as causing problems. Undoubtedly, the operations of metal and coal producers have caused varying degrees of environmental damage in mining areas, which are often located in remote regions. In the urban, suburban, and rural settings of agricultural communities, the operators of rock quarries, gravel pits, and certain industrial mines have been considered the more visible and significant offenders. Much of the concern has been focused on the concurrent and subsequent physical and aesthetic effects that their operations have had on the land—as a basic resource. Mining is only a temporary occupier of the land surface and, hence, is of a transient nature. Although active mines at any particular time are not as widespread as other land uses, they dramatically change the landscape and tend to leave evidence of their past use. Thus, the results of abandonment or closure become most conspicuous to the public. There have been continuous confrontations between citizen groups, governmental agencies, and members of the mining industry. The degree of conflict and its nature usually depended on the current land use and the estimated consequences of proposed disturbances. The conflicts centred on the following issues:

• Destruction of the landscape
• Degradation of the visual environment
• Disturbance of watercourses
• Destruction of agricultural and forest lands
• Damage to recreational lands
• Noise pollution
• Dust
• Truck traffic
• Sedimentation and erosion
• Land subsidence
• Vibration from blasting and air blasts

Environmental conscience has developed dramatically and led to widespread public opinion that governments at all levels should be able to control the depletion of natural resources and excessive environmental damage.

1.2 Uniqueness of Mining

Mineral deposits have fixed locations, so mining activities, unlike renewable resource activities (such as fishing, agriculture, and forestry), are not subject to rational selection or advanced planning. Due to unique physical conditions associated with their location, there is no choice about the characteristics of their ecological setting, the biological and chemical characteristics, mineral composition, or grade of ore in question. All of these factors influence the ultimate design, layout, and size of the operation, as well as the basic environmental problems and the potential longer range of regional impacts. The nature of the ecological setting also determines other land uses or activities that would be affected by the proposed mining.

Mines have a finite life. Because of the non-renewable nature of mineral deposits, mining is only a temporary land user. However, in some situations, ore reserves are so great that mining activities appear to be permanent fixtures in the life of the regional inhabitants.

Mines are usually located in a setting of relatively unspoiled nature. The contrast between the mine itself, its dump, mill, and newly constructed tower and the wooded valley or otherwise unscarred mountainside is always there for all to see. A generation ago, this isolated outpost of industry, winning wealth from untapped nature, was looked on as a symbol of man’s ingenuity and as a proud demonstration of progress towards an ever-expanding better future. Now it is looked on by some, perhaps by an increasing number, as a forerunner of the destruction of the environment which supports us and of which we are a part.

In many instances, the original mine is the very reason for the existence of a town. Other means of economic support are generated. Often, because of the isolated nature of these mining towns in forested and lake regions, alternative activities grow in forestry, recreation, and tourism. The latter two usually rely on increased access by a travelling public whose desire for a relatively clear, unspoiled environment contributes to changing viewpoints and increased opposition to mining activities.

The major difference between alternative land uses and mining in isolated forest, barren tundra, or alpine areas is that most alternative land uses are related to renewable resources perceived as less damaging than mining. Mining activities are also related to coal, sand, gravel, stone, and potash deposits underlying prime agricultural lands or bordering expanding urban centres. In these instances, the problem of land allocation is further compounded by political, social, economic, and environmental considerations.

How can the mineral deposits be extracted in the short term without permanently altering the land values for post-mining uses? Alternative land uses with a measurable economic value can present considerable competition for mineral-rich lands or can lead to conflicts. In some cases, no matter how economically valuable a mineral deposit is, the socio-political and environmental factors in opposition are so strong that no new mine development will take place.

Another important aspect of mine development is the time lag. After the initial discovery and evaluation of a potential mine, years of development and construction pass before a mine begins production. Time can have an important effect on the ultimate impact of...