My Crew Discovered Soil Contamination. Now What?

On what was supposed to be a routine project, a construction crew broke ground and quickly discovered something was wrong. 

 

Instead of finding the stable soil they expected, they encountered unusual odors and strange discolorations. The discovery of potential soil contamination halted their progress and left the future of the project in question.

 

Faced with this unexpected challenge, the crew needed to assess the situation, but that required expertise to help them figure out exactly what they were dealing with and how to remediate the problem. 

 

No site developer wants to experience this scenario, yet soil contamination is a significant environmental concern in the United States, affecting many areas due to industrial activities, agricultural practices and improper waste disposal. 

 

If you’re a site developer, construction manager or property owner, and you either discover or suspect contaminated soil is present in the area you are working, it’s important to work with experienced site clean-up and remediation services that can ensure the safety and viability of your project.

 

How Does Soil Contamination Happen?

 

 

Soil contamination can occur in a number of ways, from urban runoff to industrial activities. A recent news report detailed the concerns of residents in Lincoln, Calif., who say they fear ground contamination left behind from a former U.S. military missile site remains and is moving toward their homes. 

 

Some additional examples of how soil can be contaminated include:

 

• Industrial Activities: Factories and industrial plants can release pollutants into the environment through emissions, spills and improper disposal of waste. Common contaminants from industrial activities include heavy metals, solvents and chemicals used in manufacturing processes.
• Agricultural Practices: The use of pesticides, herbicides and fertilizers in agriculture can lead to the accumulation of harmful chemicals in the soil. Over time, these substances can seep into the ground and contaminate the soil and groundwater.
• Mining Operations: Mining activities can expose and spread heavy metals and other toxic substances that were previously trapped in rocks. Acid mine drainage, a process where sulfuric acid and dissolved iron leach from mines, can severely contaminate soil and water sources.
• Waste Disposal: Improper disposal of household, industrial and hazardous waste can lead to soil contamination. Landfills, especially older ones without proper lining and leachate collection systems, can leak contaminants into the surrounding soil.
• Oil Spills and Leaks: Accidental spills or leaks from storage tanks, pipelines and drilling activities can release petroleum products into the soil. These hydrocarbons can persist in the environment and cause long-term contamination.
• Urban Runoff: Runoff from urban areas can carry pollutants such as heavy metals, oils, pesticides and other chemicals from roads, parking lots and buildings into the soil.
• Atmospheric Deposition: Pollutants released into the air from industrial activities, vehicle emissions, and other sources can settle on the soil surface. These contaminants can include heavy metals, particulate matter and various organic compounds.
• Improper Use of Wastewater: Using untreated or inadequately treated wastewater for irrigation can introduce pathogens, heavy metals and other contaminants into the soil.
• Accidental Releases and Spills: Chemical spills can result in localized soil contamination, such as during transportation or storage. These incidents can occur in industrial sites, agricultural areas or residential settings.

 

While many of these contamination scenarios point to human activities, soil contamination can be naturally occurring as well. In fact, events like floods, hurricanes and earthquakes can spread contaminants from one area to another. For example, flooding can wash pollutants from industrial sites or landfills into surrounding soils.

 

As wildfires rage in the Western United States, scientists worry that surface soils set ablaze could be spreading chromium-6, a toxic compound known as the “Erin Brockovich chemical,” after the legal aid discovered it was contaminating drinking water in Hinkley, Calif. Many soils and plants are rich in naturally-occurring trivalent chromium, also known as chromium-3. Through the heating of the soil, chromium-6 could form rapidly from chromium-3, creating a toxic environment.

 

Types Of Soil Contaminants

 

 

There are several types of contaminants that pose a risk to human health when they come in contact with soil. These contaminants can go beyond polluting soil, impacting groundwater, the food chain and human health. 

 

Eight common types of soil contaminants that you may discover include:

 

1. Heavy Metals: Metals such as lead, mercury, cadmium, arsenic and chromium can accumulate in soil through industrial activities, mining, and improper waste disposal. These metals can persist in the environment for long periods and pose serious health risks to humans and ecosystems.
2. Petroleum Hydrocarbons: Petroleum products, including gasoline, diesel and crude oil, contain hydrocarbons that can contaminate soil through spills, leaks, and improper disposal. 
3. Pesticides and Herbicides: Chemicals used in agriculture, such as insecticides, fungicides and herbicides, can leach into the soil and contaminate groundwater. Persistent organic pollutants (POPs), such as DDT and PCBs, can accumulate in soil and pose long-term risks to human health and wildlife.
4. Volatile Organic Compounds (VOCs): VOCs are organic chemicals that can evaporate into the air and migrate through soil, contaminating groundwater. Common VOCs found in soil include benzene, toluene, ethylbenzene and xylene, which are associated with health effects including cancer and neurological disorders.
5. Polycyclic Aromatic Hydrocarbons (PAHs): PAHs are organic compounds formed during the incomplete combustion of organic materials, such as coal, oil and wood. They can contaminate soil through vehicle emissions, industrial activities and urban runoff.
6. Chlorinated Solvents: Chlorinated solvents, such as trichloroethylene (TCE) and perchloroethylene (PCE), are industrial chemicals used in cleaning and degreasing operations. These contaminants can persist in soil and groundwater for long periods, with human exposure linked to cancer and neurological effects.
7. Acidic and Alkaline Compounds: Soil acidity or alkalinity can be altered by the presence of acidic or alkaline compounds, such as sulfuric acid or caustic soda. These compounds can affect soil fertility, microbial activity and plant growth. When plants are exposed to these contaminants, it can lead to ecological imbalances and degradation.
8. Radioactive Materials: Radioactive contaminants, such as uranium, radium and cesium, can occur naturally or be released into the environment through nuclear accidents, mining and industrial processes. Contaminated sites pose serious health risks, including radiation exposure and long-term health effects.

 

Understanding the types of contaminants present in soil is essential for effective remediation and management strategies. Let’s take a look at who can help.

 

How Can Remediation Services Help?

 

 

When faced with the daunting discovery of soil pollution, remediation services play a crucial role in assessing, managing and restoring the affected land to ensure safety and environmental health.

 

Yet it’s critical to work with a company that has the experience and resources available to handle site remediation. The best cleanup companies will perform a site assessment, put together a proposal and discuss your options with you. 

 

Services you may need include:

 

• Sampling and laboratory analysis
• Storage tank removal
• Decontamination and decommissioning of equipment
• Site remediation that may include asbestos disposal or mercury cleanup
• Phase I and Phase II site assessments
• Remediation-specialized engineered shoring excavations
• Weatherization to further protect your site from more contamination
• Hazardous waste transportation
• Hazardous waste disposal

 

A partner experienced in handling contaminated soil can also walk you through your options and answer questions you have about what happens next. 

 

How Soil Contamination Is Addressed

 

 

Depending on the nature of your contaminated soil, different remediation options may be available to effectively address and mitigate the specific contaminants present.

 

For example, crews may excavate and physically remove the contaminated soil from the site using the appropriate equipment. This step is often necessary for heavily contaminated areas. Hazardous waste disposal companies will then transport the contaminated soil to a designated treatment or disposal facility using secure containers.

 

Another option is using treatment or containment methods, including the following:

 

• On-Site Treatment (In-Situ): Treat the contaminated soil directly at the site using methods such as bioremediation (using microbes to degrade contaminants), soil vapor extraction, or chemical oxidation.
• Off-Site Treatment (Ex-Situ): Transport the contaminated soil to an off-site facility for treatment. Methods include soil washing, thermal desorption (heating the soil to remove contaminants) and incineration.
• Capping: Cover the contaminated soil with an impermeable barrier, such as a layer of clay or synthetic material, to prevent exposure and limit the spread of contaminants.
• Containment Walls: Construct barriers around the contaminated area to isolate it and prevent the spread of contaminants to surrounding soil and groundwater.

 

Other options include restoration and reclamation, in which experts add clean soil, organic matter and nutrients to restore soil health and support plant growth. Planting vegetation can also help stabilize the soil, prevent erosion and promote ecological recovery.

 

You will likely have to continue monitoring the site after remediation to ensure that the contaminants have been effectively removed or contained. This may involve regular soil and groundwater testing. 

 

 

Why A Hazardous Waste Transporter Is Key To The Process

 

 

Hazardous waste disposal companies handle the crucial task of transporting contaminated soil from the site to designated treatment or disposal facilities, ensuring safety, compliance and efficiency throughout the remediation process.

 

By partnering with a company that offers both remediation services and waste transport, you can ensure seamless coordination between soil removal and transportation.

 

Transporting contaminated soil also involves navigating a complex web of environmental regulations and permitting requirements at the local, state and federal levels. Hazardous waste transporters have the knowledge and experience to ensure full compliance with these regulations, minimizing the risk of legal and regulatory issues.

 

Remediators and transporters are typically equipped with specialized vehicles, containers and safety gear designed specifically for handling hazardous materials. They follow strict safety protocols to prevent spills, leaks and exposure to harmful contaminants during transportation.

 

They will also assist with the required documenting and reporting process, including manifests, permits and tracking records. Their expertise, compliance with regulations, safety measures and efficient transportation services are invaluable in achieving successful soil remediation outcomes.