ALC - earthenviro

Comprehensive Contaminated Land & Site Investigations

Written by John Macintyre | Oct 14, 2024, 4:58:37 PM

Comprehensive Contaminated Land & Site Investigations

Environmental Remediation

Expert Site Investigations for Contaminated Land

Why Site Investigations Are Essential for Contaminated Land

Contaminated Land & Site Investigations. Site investigations are a critical first step when developing land that may be contaminated. The process involves a detailed assessment of the soil and groundwater conditions to identify the presence of harmful substances such as heavy metals, chemicals, or industrial by-products. Contaminated land can pose significant risks to public health, the environment, and the structural integrity of any development built on the site.

Earth Environmental & Geotechnical Ltd. (EEG) specialises in conducting thorough contaminated land assessments to ensure that sites are safe for future use. Our team of experienced geotechnical engineers offers a comprehensive range of site investigation services, tailored to meet regulatory standards and client-specific needs.

Our Contaminated Land Investigation Services

At Earth Environmental & Geotechnical Ltd., we provide a wide variety of site investigation services to help identify and manage contamination issues, ensuring full compliance with environmental and safety standards. Our services include:

Each stage of the process is designed to provide clients with a clear understanding of any potential contamination risks and the steps necessary to mitigate these risks.



Common Contaminants Found in Site Investigations

Heavy Metals and Industrial By-products

Contaminated land often contains hazardous materials such as heavy metals (lead, arsenic, mercury), hydrocarbons, and asbestos from former industrial activities.

During site investigations, identifying and assessing contaminants is crucial to ensure the safety of the environment and public health. Contaminants vary based on the history and use of the site, but several types are frequently encountered in soil, groundwater, and other environmental media.

  1. Petroleum Hydrocarbons
    Petroleum-based contaminants, such as gasoline, diesel, and oil, are common in areas with a history of industrial or commercial activities like gas stations and vehicle maintenance facilities. These substances can leach into the soil and groundwater, leading to long-term environmental damage if not properly managed.
  2. Heavy Metals
    Heavy metals, including lead, mercury, cadmium, and arsenic, are frequently found at sites that were once industrial operations or older manufacturing plants. These metals are persistent in the environment and pose significant health risks, including neurological and organ damage.
  3. Volatile Organic Compounds (VOCs)
    VOCs are chemicals that easily evaporate into the air and are often found at industrial and commercial sites. Common VOCs include benzene, toluene, and trichloroethylene (TCE). These contaminants can affect air quality and pose risks to human health through inhalation or groundwater contamination.
  4. Polychlorinated Biphenyls (PCBs)
    PCBs were widely used in electrical equipment and other industrial applications until they were banned in the late 20th century. Despite the ban, they persist in many older sites and are highly toxic, with significant environmental and health risks.
  5. Pesticides
    In agricultural areas or locations previously used for farming, pesticides like DDT, aldrin, and dieldrin are common contaminants. These chemicals, designed to kill pests, can have long-lasting effects on soil and water quality, as well as human and animal health.
  6. PFAS – perfluoroalkyl substances are also known as forever chemicals and are ubiquitous.PFAS are a group of manufactured chemicals that have been used in industry and consumer products since the 1940s because of their useful properties.

Understanding these common contaminants helps guide proper remediation strategies, ensuring safer land reuse and reducing potential hazards.

One such material commonly found in historical industrial sites is galligu, a by-product of the 19th-century soap manufacturing process. Galligu is a significant contaminant due to its high levels of arsenic and heavy metals.







Case Study: Site Investigation of Contaminated Land in St. Helens, North West England



Interesting Find in a Window Sampling Borehole

Earth Environmental & Geotechnical Ltd. conducted a site investigation in St. Helens, North West England, as part of a land development project. The investigation uncovered galligu, a hazardous by-product of the soap manufacturing LeBlanc process, used in the 19th century to produce soda ash from sodium carbonate.

What Is Galligu?

Galligu is primarily composed of calcium sulphate (anhydrite), and it often contains elevated levels of arsenic and other heavy metals. While dry, galligu has a silty sand-like texture, but when exposed to water, it softens, becoming thixotropic, resembling toothpaste in consistency. When hydrated under anaerobic conditions, such as exposure to rainwater, galligu produces hydrogen sulphide, which emits a strong “rotten egg” odor.

Galligu is not only hazardous due to its chemical properties but also because of its highly alkaline pH, which can damage construction materials and affect the stability of any structure built on contaminated land. The discovery of galligu necessitated a specialized remediation plan to safely manage and mitigate its impact on the site’s future use.

How Earth Environmental & Geotechnical Ltd. Can Help with Contaminated Land

With years of expertise in contaminated land investigations, Earth Environmental & Geotechnical Ltd. ensures that all site assessments are handled with precision and professionalism. We collaborate closely with regulatory bodies, local authorities, and clients to ensure safe and effective solutions for even the most challenging contaminated sites.

Our team has experience working on various sites across the UK, including industrial, residential, and commercial developments. By conducting thorough investigations, we can help developers make informed decisions, safeguard public health, and ensure compliance with all environmental regulations.

Contact us today to discuss how we can assist with your contaminated land and site investigation needs.

At Earth Environmental & Geotechnical Ltd. we work with our clients to ensure there is a detailed understanding and risk assessment of all development sites. Consideration of Contaminants should be included at the earliest point of site investigation and included in the Phase 1 Desk Study
View full post