Environmental Geology

Environmental geology is an applied scientific discipline concerned with the practical use of geological principles to understand, mitigate, and resolve environmental problems generated by human activities. It draws upon knowledge of the lithosphere, hydrosphere, biosphere, and atmosphere to examine how human societies interact with their geological surroundings. Closely aligned with hydrogeology and engineering geology, and with links to environmental geography, the field has gained increasing prominence as population growth, industrialisation, and resource depletion intensify pressure on the Earth’s natural systems. By applying geological insight, environmental geology seeks to minimise degradation, manage resources sustainably, and ensure that development decisions are aligned with the long-term health of the environment.

Environmental Geology and Related Disciplines

Environmental geology is inherently multidisciplinary and intersects with several other earth and environmental sciences. Its scope includes the study of natural systems, the assessment of anthropogenic impacts, and the identification of solutions that balance environmental protection with human needs. Specialists rely on geological mapping, geophysical surveys, ground investigations, geomorphological analysis, hydrological modelling, and ecosystem assessment to diagnose and address environmental issues.

Hydrogeology

Hydrogeology focuses on the movement, distribution, and quality of groundwater within soils and rock formations in the Earth’s crust. Environmental geology plays a vital role in this field because human activities such as mining, agriculture, industrial processing, and urban development can contaminate aquifers. Groundwater pollution may result from chemicals, bacteria, or thermal alterations, with common sources including agricultural fertilisers, leaking sewer systems, polluted surface waters, and mining wastes.
Environmental geology provides a structured approach to monitoring groundwater contamination. Key objectives typically include:

• determining the extent, nature, and severity of contamination
• analysing hydrological parameters and propagation mechanisms
• detecting pollutant migration towards sensitive or critical areas
• assessing the efficacy of immediate remediation actions
• recording long-term data to ensure compliance with environmental standards
• conducting research to refine and validate hydrogeological models

Through these applications, environmental geology supports the development of effective countermeasures, informed remediation, and sustainable groundwater management.

Soil Science

Soil science examines soils as natural resources and concerns itself with soil formation, classification, fertility, and conservation. Environmental geology contributes to this field by addressing challenges posed by land degradation, declining arable land, population growth, and rising demand for food production. Soil surveys are among the principal tools used to evaluate land capability and to guide agricultural and urban planning.
Such surveys offer insights into:

• soil erosion rates
• depth and profile of soil horizons
• slope steepness and stability
• shrink–swell potential
• presence of rock outcrops
• risks of salinisation
• crop responses to fertilisers
• suitability for specific cropping systems

The information supports decisions about land-use allocation, soil management, forestry planning, and the mitigation of environmental impacts from improperly managed land.

Key Focus Areas of Environmental Geology

Environmental geology encompasses a wide range of tasks associated with natural resource management, hazard mitigation, and pollution control. Its major areas of focus include:

• management of geological and hydrogeological resources, including fossil fuels, minerals, surface water, and groundwater
• geomorphological and edaphological assessments of Earth’s surface processes
• identification and mitigation of natural hazards such as landslides, earthquakes, coastal erosion, and floods
• waste management for industrial and domestic sectors
• reduction or prevention of pollution through monitoring and remediation
• provision of expert assessments for litigation and regulatory compliance

These areas place environmental geology at the centre of contemporary environmental challenges, including population expansion, diminishing natural resources, and global land-use change.

Mining and Environmental Impact

Mining has been an essential human activity since prehistoric times and remains central to modern economies. However, it is constrained by local geology: extraction is only feasible where mineral deposits are present and economically viable. Once a deposit is exhausted, mining operations must cease, and the resulting disturbances can be substantial.
Environmental impacts associated with mining commonly include:

• landscape defacement
• release of chemically active waste materials
• production of dust and fine particulates capable of contaminating surface waters
• long-term geochemical changes that can affect ecosystems

Environmental geology plays a critical role in reducing these impacts by assessing geological conditions prior to mining, guiding land-use decisions, and contributing to environmental management plans. In jurisdictions such as Brazil and Australia, rehabilitation of mined land is mandated by law, requiring site restoration after extraction ends. Geologists also provide key evidence in litigation associated with pollution events and ensure that mining operations incorporate best-practice mitigation strategies.

Recycling and Resource Sustainability

Environmental geology is central to debates about the depletion of non-renewable resources such as fossil fuels and metals. These finite materials are foundational to energy systems, transport, manufacturing, and infrastructure, yet they are consumed at accelerating rates. To address these pressures, the field promotes recycling and reuse as methods of extending resource life and reducing the environmental burdens associated with extraction and waste disposal.
Recycling involves collecting, sorting, and reprocessing consumer and industrial goods into raw materials for new products. Reuse and recycling occur at both individual and industrial scales and include practices such as:

• composting of organic waste to produce soil conditioners
• freecycling, in which goods are exchanged to avoid new purchases
• dismantling and repurposing large manufactured items
• improving material quality through processing to create higher-value products

These practices reduce waste volumes, minimise pollution, and contribute to sustainable material management by closing resource loops.

Land Use Planning

Effective land use planning is essential to reduce the exposure of populations and infrastructure to natural hazards and to limit negative human impacts on the environment. Environmental geology informs these decisions by analysing how water, materials, energy, and land systems respond to human settlement and industrial activity. New sites for industrial development, mining, and waste disposal must be carefully selected to ensure that pollutants cannot easily migrate into surrounding ecosystems.
Site investigations typically occur in two phases:
Orientating investigations, which rely on:

• topographic maps and remote-sensing data
• information on vegetation, settlement patterns, and transportation routes
• climatic data (precipitation, temperature, evapotranspiration, wind conditions)
• hydrological conditions including streams, lakes, springs, and groundwater quality
• geological structures, stratigraphy, and soil types
• ecological considerations such as protected areas and water conservation zones

Detailed investigations, which include:

• field reconnaissance
• assessment of geological units, their thicknesses, and lateral extent
• analysis of lithology, homogeneity, bedding conditions, fractures, and tectonic features
• evaluation of weathering impacts, groundwater dynamics, and soil stability