Asbestos in Soil: What You Need to Know

How asbestos gets into soil

Asbestos in soil is more common than many people realise, particularly in areas with a history of industrial activity, demolition, or fly-tipping. The most frequent sources of soil contamination in the UK are:

• Demolition and construction waste: When asbestos-containing buildings are demolished — particularly before the 1980s, when asbestos regulation was limited — rubble, cement sheets, and lagging were sometimes buried on site or used as hardcore fill. This is the most common source of asbestos in residential gardens and development sites.
• Fly-tipping: Asbestos-containing materials are frequently fly-tipped in rural areas, on brownfield land, and in gardens. Corrugated cement sheets, pipe lagging, and insulation boards are the most commonly tipped materials.
• Industrial contamination: Former industrial sites — particularly those associated with shipbuilding, power generation, textiles, and manufacturing — may have widespread asbestos contamination in the ground from decades of use and inadequate disposal.
• Natural occurrence: In some parts of the world, asbestos occurs naturally in rock formations and can be present in soil as a result of geological processes. This is rare in the UK but has been recorded in parts of Cornwall and Scotland.
• Previous asbestos removal works: Poorly conducted asbestos removal — particularly historical removals carried out before modern regulations — can leave residual fibre contamination in soil around a building.

Health risks of asbestos in soil

The health risk from asbestos in soil depends primarily on whether the asbestos is in a form that can release airborne fibres. Asbestos that is fully encapsulated within cement or other binding materials — such as intact corrugated sheets — presents a relatively low risk when undisturbed. The risk increases significantly when:

Identifying asbestos in soil

Asbestos in soil is not always visually obvious. Large fragments of corrugated cement sheet or pipe lagging are relatively easy to identify, but smaller fragments, fibrous material, and heavily degraded ACMs can be difficult to distinguish from ordinary rubble or organic matter.

Common visual indicators of asbestos contamination in soil include:

• Grey or white fibrous material in or on the soil surface
• Fragments of corrugated sheet material (grey or grey-green)
• Pipe lagging — white or grey insulation material around pipe fragments
• Flat board fragments with a layered or laminated appearance
• White or grey granular material mixed into the soil

Visual identification is not sufficient to confirm the presence of asbestos. Laboratory analysis of soil samples is required for a definitive result. Never handle suspected asbestos material with bare hands — if you need to move it, use gloves and a sealed bag.

Asbestos in soil assessment

A formal asbestos in soil assessment follows a structured methodology designed to characterise the extent and nature of contamination. The process typically involves:

Regulations and legal duties

Asbestos in soil is regulated under several overlapping legislative frameworks in the UK:

Remediation options

The appropriate remediation strategy depends on the extent and nature of contamination, the planned use of the site, and the risk assessment findings. The principal options are:

Asbestos in garden soil

Finding asbestos in a residential garden is a relatively common occurrence in properties built before 1985, particularly where garages, sheds, or outbuildings have been demolished. The most frequently encountered materials are fragments of corrugated asbestos cement sheet and pipe lagging.

If you discover suspected asbestos in your garden, the recommended steps are:

• Stop any digging or gardening work in the affected area immediately.
• Keep children and pets away from the area.
• Do not attempt to pick up or bag the material yourself without appropriate PPE and training.
• Dampen the area lightly with water to suppress any loose fibres — do not use a hose at pressure.
• Contact a licensed asbestos contractor for a site assessment and quotation.
• If the material is clearly identifiable as asbestos cement sheet and is in a small, discrete area, some contractors can collect it as part of a waste collection service.

For small quantities of intact asbestos cement fragments in a garden, the risk is relatively low provided the material is not disturbed. However, professional assessment and removal is always the safest course of action. See our Asbestos in Soil Assessment service for more information.

Asbestos on development sites

Developers and contractors working on brownfield land or former industrial sites have a legal duty under CDM 2015 to identify and manage asbestos risks in the ground before work commences. Failure to do so can result in enforcement action by the HSE, significant remediation costs, and project delays.

A pre-construction asbestos in soil assessment should be commissioned as part of the site investigation process for any development on land with a history of industrial use, demolition, or unknown fill. The assessment should be carried out by a competent specialist and the findings incorporated into the Construction Phase Plan.

Where asbestos is found during groundworks, all work in the affected area must stop immediately. The site must be secured, the HSE notified if appropriate, and a licensed asbestos contractor engaged to assess and remediate the contamination before works can resume.

Assessment and remediation costs

Costs vary considerably depending on the size of the site, the extent of contamination, and the remediation method required. The following table provides indicative ranges for the most common scenarios.

All costs are indicative. Contact Pro Asbestos Removal for a precise quotation based on your specific site and requirements.