The Dangers of Contaminated Soil: What You Need to Know

August 8, 2023

Last updated: February 2026

Introduction

Contaminated soil is a serious issue that affects the health and well-being of both humans and the environment. It is defined as soil that has been polluted with harmful chemicals, pollutants, or other hazardous materials, such as asbestos and different types of fuel (petrol and diesel).

In this article, we will explore the dangers of contaminated soil, the causes of soil contamination, and the effects it has on community health and the environment. We will also discuss remediation and prevention techniques, as well as the role of government and industry in addressing this problem.

In Australia, contaminated soil is commonly identified during property transactions, development applications, infrastructure projects, and construction works, where contaminated land management is often required to address health, environmental, and regulatory risks.

What are the causes of soil contamination?

Industrial and commercial sources

Industrial pollution is one of the major causes of contaminated soil. Factories and industrial plants can release a wide range of pollutants into the air and water sources (groundwater and surface water), which can then settle onto the ground and contaminate the soil. These pollutants can include heavy metals, chemicals, and pesticides.

Agricultural practices

Agricultural practices, such as the use of pesticides and fertilisers, can also contribute to soil contamination. The overuse of these chemicals can lead to a buildup of harmful substances in the soil, which can be harmful to both community health and the environment.

Improper waste disposal and dumping

Improper disposal of hazardous waste, such as chemical waste or medical waste, can also lead to soil pollution. Landfills and illegal dumping sites are common sources of soil contamination. If these materials are not properly managed, they can leach into the soil and contaminate it.

Leakage from underground storage tanks, such as petroleum, diesel and oil tanks, can also be a source of soil contamination. These tanks can corrode over time and release harmful chemicals into the soil.

Common indicators of potential contamination

Common indicators that soil contamination may be present include:

Historical industrial or commercial land use
Evidence of dumping or fill of unknown origin
Former or existing service stations or workshops nearby
Legacy asbestos-containing materials
Underground petroleum or fuel storage systems
Sites impacted by spills, leaks, or fires

These indicators are often used to determine whether further investigation is required.

Concerned about potential soil contamination? Request a scope and quote to assess your site.

What are the effects of contaminated soil on community health?

Exposure pathways

Exposure to contaminated soil can have a significant impact on community health. The exposure routes to contaminated soil can include inhalation, ingestion, or skin contact.

Short-term health effects

Short-term health effects from exposure to contaminated soil can include respiratory problems, skin irritation, and headaches. These symptoms can be temporary and may go away once the person is no longer exposed to the contaminated soil.

Long-term health risks

Long-term exposure to contaminated soil can lead to more serious health problems, such as different types of cancer and neurological disorders. These effects can be particularly severe for vulnerable populations, such as children and the elderly, who are at a higher risk of health problems.

How exposure commonly occurs

Exposure to contaminated soil may occur through:
‍

Breathing in contaminated dust or fibres
Hand-to-mouth contact, particularly in children
Direct skin contact during excavation or construction works
Tracking contaminated material into vehicles, buildings, or homes
‍

Understanding these pathways helps inform appropriate site management and control measures.

For development and construction projects, identifying contamination early allows appropriate controls, investigations, and remediation strategies to be implemented before works commence.

What are the effects of contaminated soil on the environment?

Impacts on ecosystems and biodiversity

Contaminated soil can also have a significant impact on the environment. It can damage ecosystems and harm wildlife and plant life. For example, contaminated soil can lead to the death of plants and animals and can make it difficult for new life to take hold in the area.

Impacts on water resources

Contaminated soil can also lead to the corruption of water sources, which can have a ripple effect on the entire ecosystem. For example, if a water source is contaminated with harmful chemicals, it can be harmful to the fish and other aquatic life that depend on it.

Long-term environmental consequences

Environmental impacts of contaminated soil may include:
‍

Reduced soil fertility and loss of vegetation
Bioaccumulation of contaminants in plants and animals
Migration of contaminants into groundwater and surface water
Long-term ecosystem degradation beyond the original site boundary
‍

These impacts can extend well beyond the source area if contamination is not identified and managed appropriately.

‍

How do you remediate & prevent contaminated soil?

Common remediation techniques

Remediation and prevention are critical in addressing the problem of contaminated soil. There are several techniques that can be used to clean up contaminated soil, including:
‍

Physical removal of contaminated soil: This technique involves digging up the contaminated soil and hauling it away to a properly managed landfill or other disposal site.
In situ treatment methods: This technique involves treating the contaminated soil on-site, rather than removing it. This can include techniques such as soil stabilisation, solidification and encapsulation.
Bioremediation: This technique involves using microorganisms to break down harmful chemicals in the soil.
Phytoremediation: This technique involves using plants to extract harmful chemicals from the soil.
‍

Remediation is often part of a broader contaminated land management process that considers site conditions, regulatory requirements, and the intended land use.

Prevention and best practice management

Best practices for preventing soil contamination include proper waste management, sustainable agricultural practices, and regular monitoring of industrial and agricultural activities. Governments and industries play a critical role in regulating and enforcing these best practices to prevent and clean up contaminated soil.

Proper waste management is an important aspect of preventing soil contamination. This includes properly disposing of hazardous waste and ensuring that landfills and waste disposal sites are properly managed.

Sustainable agricultural practices, such as reducing the use of pesticides and fertilisers, can also help to prevent soil contamination. Additionally, farmers can implement practices such as crop rotation and soil conservation to help protect the soil from contamination.

Regular monitoring of industrial and agricultural activities is also important in preventing soil contamination. This can include monitoring for leaks and spills, as well as regular testing of soil and water to ensure that they are not contaminated.

Remediation planning for development projects

For development and construction projects, remediation planning often involves:
‍

Confirming contamination extent through investigation
Determining appropriate remediation strategies
Managing contaminated soil during excavation
Classifying soil and waste for transport and disposal
Validation sampling to demonstrate the site is suitable for its intended use
‍

Early planning helps reduce delays and unexpected costs during construction.

Conclusion

Contaminated soil is a serious issue that affects the health and well-being of both humans and the environment. It is caused by industrial pollution, agricultural practices, improper disposal of hazardous waste, and leakage from underground storage tanks. The effects on human health and the environment can be severe. Remediation and prevention techniques, as well as the role of government and industry, are crucial in addressing this problem.

It is important that we take action to prevent and clean up contaminated soil to protect the health and well-being of future generations. Individuals, industry, and government must work together to ensure the safety of our soil for the benefit of all.

Need clarity before you build, buy, or develop? Request a scope and quote for your project.

Frequently Asked Questions

How do I know if my site might have contaminated soil?

Common indicators include historical industrial or commercial land use, unknown or imported fill, nearby service stations, evidence of dumping, legacy asbestos materials, or underground fuel storage systems.

What contaminants are commonly assessed in Australia?

This depends on site history, but commonly assessed contaminants include hydrocarbons (fuel and oils), heavy metals, pesticides, asbestos, and in some cases PFAS where relevant.

Can contaminated soil delay construction or development?

Yes. If contamination is identified, investigation, waste classification, remediation, and validation may be required before earthworks or construction can proceed, potentially affecting timelines and approvals.

Is contaminated soil always required to be removed?

Not always. Depending on the type and extent of contamination, soil may be managed on site using containment or treatment methods, or removed and disposed of at an approved facility.

Who is responsible for managing contaminated soil on a project?

Responsibility typically sits with the property owner or developer, with investigations and remediation managed by suitably qualified environmental consultants in line with regulatory requirements.



Apr 8, 2026

Site Investigation Explained: Boreholes, Sampling, Lab Testing, and Reporting





Apr 2, 2026

Geotechnical Services: When You Need Them and What to Expect





Mar 24, 2026

Environmental Drilling in Constrained Urban Sites

