Soil is a mixture of various components, including minerals and microorganisms1. It is a vital resource that we rely on, directly or indirectly, every day. Due to its physical composition, soil can absorb and harbour various elements. This quality can be beneficial when it boosts nutrient content, but it can also be dangerous when it absorbs contaminants.
Pollutants from various sources can seep into soil over time2. The extent of contamination depends on the source of the pollutant and the environment the organic matter is in. In this post, we’ll explore all things soil contamination, including treatment methods.
Table of Contents
- What is Soil Contamination?
- How Does Soil Contamination Occur?
- How Does Soil Contamination Affect the Environment?
- How Does Soil Contamination Affect Human Health?
- How to Test Soil for Contaminants
- Where Does Contaminated Soil Go?
- Where is Soil Contamination the Worst?
- How is Contaminated Soil Treated?
What is Soil Contamination?
Also known as soil pollution, soil contamination impacts the dirt or organic matter of an area of land. Soil contamination affects the environment and is often caused by humans and our activities. Once soil has been contaminated, only extended periods of time or decontamination processes can return it to a natural state.
How Does Soil Contamination Occur?
Soil may become contaminated due to various circumstances. From the surface, agricultural practices, particularly those that use chemicals, can cause soil contamination, as can improper handling of waste. Other concerns may come from below the soil and be caused by the leakage of buried pipes or tanks. Occasionally, groundwater or rainwater may be to blame, or dust contaminants being carried through the air.
How Does Soil Contamination Affect the Environment?
Once a pollutant is leaked into the soil, it alters the composition of this organic matter. Contaminants can reduce the biodiversity of the soil and, thus, the number of nutrients present in it3. This change could impact nearby plants and the animals that eat them. Soil contamination may further harm the environment by causing air pollution or leaking into nearby water sources.
How Does Soil Contamination Affect Human Health?
Depending on the extent of the exposure and the level of contamination, polluted soil can have various impacts on human health. Absorption through the skin can lead to multiple irritations, such as hives, and can trigger allergies. If you ingest food that has come into contact with contaminated soil, the pollutants could be absorbed into your circulatory system and cause severe health changes4. Even simply inhaling contaminated soil can be cause for concern5.
How to Test Soil for Contaminants
If you suspect an area where you are building is affected by contaminated soil, the first step is to get it tested. You can contact a private laboratory or local soil testing facility, such as a university, to do so. While methods may differ, these tests look for various compounds within the soil to determine the extent of the contamination. Once complete, they will inform you of the best course of action regarding your contaminated soil treatment method.
Soil Acidity
The pH of the soil is crucial to understanding whether it will need a contaminated soil treatment. It detects how many hydrogen ions are present in the dirt and may further determine the pollutants causing the soil to be more acidic or basic.
Nutrient Analysis
Clean soil will have a healthy amount of nutrients to support the ecosystem around it. Contaminated soil may lack certain nutrients or have an overabundance of others.
Heavy Metals
Chromium, arsenic, cadmium, and lead are some metals that can be present in soil. These elements can cause significant concerns and negatively impact the environment by affecting plant lifecycles.
Where Does Contaminated Soil Go?
Once testing has been completed, the recommended method of cleaning the contaminated soil might be to remove it from the site. Excavation can occur if the sample area is minimal or treatment is required off-site. Contaminated soil can be moved to a landfill or disposal centre, where treatment will be performed to ensure it does not cause further harm.
The safe remediation of contaminated soil is best left to professionals who understand the contaminants they are working with and the proper methods used to ensure individuals are left with clean soil. At Inflector Environmental Services, our processes meet the highest standards for soil remediation. If you’ve completed testing and need support regarding contaminated soil treatment methods, reach out to us. We’re here to help.
Where is Soil Contamination the Worst?
Areas and locations where contaminated soil is more prominent tend to be urban settings. However, former industrial sites can also be heightened places where this type of soil is found. There might be a few reasons for this, but the overarching theme is human activity. Land development, industrial dumping, and waste disposal are all more likely in these areas.
How is Contaminated Soil Treated?
Since many different contaminants might impact soil, there are a few different treatment methods (such as excavation, mentioned above) used depending on the type of pollutant present. These methods may be used singularly or in combination to return the soil to a clean state.
Biological Treatment
Also known as bioremediation, this method of cleaning contaminated soil is used for various contaminants, including heavy metals and non-chlorinated pesticides or herbicides. Microorganisms, such as bacteria or fungi, are released into the ground and consume the contaminant as a food source6.
Chemical Oxidation
This contaminated soil treatment method uses reactive chemical oxidants to destroy present pollutants. It’s considered a versatile solution and useful for sites with extreme soil depths or areas underneath buildings. Chemical oxidation cleans soil that has been contaminated by various hydrocarbons.
Soil Stabilization
During soil stabilization, contaminants are trapped or stabilized in the soil so they cannot cause potential harm to the environment or human health. This treatment can be accomplished by modifying the pollutant to a less dangerous state or immobilizing it in place so it doesn’t seep into other areas.
Soil Washing
A similar process to the name, soil washing separates finer dirt and earth, like silt and clay, from coarse aggregates like sand and gravel. Both silt and clay are more likely to bind to contaminants due to their physical makeup. However, this method does not remove pollutants, just the soil layers they cling to, so the contaminated soil must be taken to a facility for further extraction.
Work with the Experts
If your site requires soil remediation, trust the hazardous materials abatement pros at Inflector, where we live by our motto: jobs done safe, jobs done right. Our soil remediation services are uniquely tailored to each project we take on. Our team provides unique and advanced solutions in order to expedite timelines and exceed our clients’ needs.
Want to see our work in action? Visit our Projects page to see some of the impressive soil remediation projects (like this one) that our team has completed for our clients.
Interested in learning more about the Inflector difference? Contact us today, our team is always eager to help.
Sources:
- Canada, Natural Resources. 2011. “Soil.” www.nrcan.gc.ca. September 14, 2011. https://www.nrcan.gc.ca/our-natural-resources/forests/sustainable-forest-management/conservation-and-protection-canadas-forests/soil/13205.
- Environmental pollution Centers. 2017. “What Is Soil Pollution | Environmental Pollution Centers.” environmentalpollutioncenters.org. 2017. https://www.environmentalpollutioncenters.org/soil/.
- Perrino, E. V., G. Brunetti, and K. Farrag. 2014. “Plant Communities in Multi-Metal Contaminated Soils: A Case Study in the National Park of Alta Murgia (Apulia Region – Southern Italy).” International Journal of Phytoremediation 16 (9): 871–88. https://doi.org/10.1080/15226514.2013.798626.
- Soil Science Society of America. n.d. “Soil Contaminants | Soil Science Society of America.” www.soils.org. https://www.soils.org/about-soils/contaminants/.
- Sheehan, P. J., D. M. Meyer, M. M. Sauer, and D. J. Paustenbach. 1991. “Assessment of the Human Health Risks Posed by Exposure to Chromium‐Contaminated Soils.” Journal of Toxicology and Environmental Health 32 (2): 161–201. https://doi.org/10.1080/15287399109531476.
- Martín Moreno, Carmen, Aldo González Becerra, and María José Blanco Santos. 2004. “[Biological Treatments for Contaminated Soils: Hydrocarbon Contamination. Fungal Applications in Bioremediation Treatment].” Revista Iberoamericana de Micologia 21 (3): 103–20. https://pubmed.ncbi.nlm.nih.gov/15709784/.