Ground Contamination and Brownfield Land, What Buyers Need to Check

What is Ground Contamination?

Ground contamination refers to the presence of hazardous substances, such as heavy metals, petroleum hydrocarbons, solvents, asbestos, or other chemicals, in the soil or groundwater beneath or adjacent to a property. Contamination typically arises from former industrial uses: gasworks, factories, petrol stations, dry cleaners, landfill sites, tanneries, and similar activities that historically handled hazardous materials.

Properties on or near former industrial land are described as brownfield sites. The government has actively encouraged the development of brownfield land to reduce pressure on greenfield sites, meaning new-build homes on former industrial land are increasingly common.

The Regulatory Framework

Ground contamination in England and Wales is principally regulated under Part IIA of the Environmental Protection Act 1990. Under this framework, local authorities are responsible for identifying and inspecting land within their area that may be contaminated, and for serving remediation notices on those responsible.

The Environment Agency takes enforcement action on the most serious contamination cases, particularly where there is a risk to controlled waters (rivers, aquifers, and groundwater).

Homes England, which oversees regeneration of brownfield sites, typically requires remediation of any significant contamination as a condition of development consent for new-build schemes.

Categories of Contamination Risk

The Phase 1 and Phase 2 Survey Process

**Phase 1, Desk Study:** A desktop review of historical maps, records, and environmental data to identify any former industrial or commercial uses of a site and neighbouring land. This produces a conceptual site model and a risk assessment. Phase 1 studies are commonly carried out on new-build sites before development and the report should be available from the developer.

**Phase 2, Ground Investigation:** Where Phase 1 identifies a potential risk, a Phase 2 investigation involves physical sampling and testing of soil and groundwater. Results are assessed against Environment Agency screening values to determine whether remediation is required.

Who is Liable for Contaminated Land?

Under Part IIA, liability falls primarily on the person who caused or knowingly permitted the contamination (the "polluter"). If the original polluter cannot be found, liability may pass to the current owner or occupier of the land. This is known as the "owner/occupier" fallback.

For property buyers, this means it is possible, in limited circumstances, to become liable for cleaning up contamination caused by a previous owner or industrial occupier of the site. This underlines the importance of due diligence before purchase.

What Buyers Should Do

• Commission an environmental search (available from specialist providers) as part of the conveyancing process, your solicitor should arrange this routinely
• For properties on known former industrial land, request copies of any Phase 1 or Phase 2 reports from the developer or seller
• Ask your solicitor whether any Part IIA designation, remediation notice, or monitoring agreement affects the title
• For high-value purchases or sites with uncertain history, consider commissioning an independent Phase 1 desk study

Property Passport UK displays land use history and environmental risk flags for properties in its index, including information sourced from the Environment Agency, to help buyers identify whether a property warrants closer environmental scrutiny before proceeding.