TA6 Contaminated Land: What to Declare

If you are selling a property in England or Wales that sits on or near land with an industrial, commercial, or agricultural history, the contaminated land questions on the TA6 Property Information Form deserve careful attention. Section 7 of the TA6 deals with environmental matters, and the answers you give about contamination become part of the legal transaction.

Getting these answers right protects you from post-completion claims. Getting them wrong — or leaving them incomplete — can expose you to a misrepresentation claim and create exactly the kind of delay that causes sales to collapse.

This guide explains what the TA6 asks about contaminated land, how to answer each question, what evidence to gather, and how to handle the situation if contamination is flagged during your buyer's searches.

What the TA6 asks about contaminated land

Section 7 of the TA6 (Environmental Matters) contains several sub-questions that relate directly to contaminated land. While the exact wording varies slightly between editions, the core questions are:

• Is the property or any nearby land affected by contamination? — This covers land that has been formally determined as contaminated under Part 2A of the Environmental Protection Act 1990, as well as land you suspect may be contaminated based on its previous use.
• Have you received any notice or correspondence from the local authority about contaminated land? — This includes letters about Part 2A investigations, remediation notices, and consultation on nearby contaminated sites.
• Are there any environmental problems that affect the property or nearby land? — A broader question that catches issues not covered by the specific contamination question, such as odour from a nearby industrial process or polluted watercourses.

The form also asks about flooding, Japanese knotweed, radon, and energy performance in the same section, but it is the contamination questions that cause sellers the most difficulty. For guidance on the full Section 7, see our guide on TA6 Section 7: Environmental Matters.

What counts as contaminated land

Under Part 2A of the Environmental Protection Act 1990, land is legally contaminated if substances in, on, or under the land are causing, or have a significant possibility of causing, significant harm to human health, property, or controlled waters. The statutory definition requires a pollutant linkage — a source of contamination, a pathway through which it can reach a receptor, and a receptor (such as residents or a watercourse) that is being or could be harmed.

For the purposes of the TA6, however, you do not need to apply this legal test yourself. You simply need to disclose what you know. Common situations where contaminated land questions become relevant include:

• Properties built on former industrial sites — factories, gasworks, chemical plants, metalworks, tanneries
• Properties near or on former petrol stations, dry cleaners, or vehicle repair workshops
• Homes built on infilled land — former quarries, gravel pits, or ponds filled with unknown material
• Properties close to current or former landfill sites
• Land in former mining areas where spoil heaps or mine tailings may have left heavy metals in the soil
• Properties on converted agricultural land where persistent pesticides, herbicides, or fuel storage may have left residues

If any of these apply to your property, you should say so on the TA6. For a full overview of how contaminated land affects a sale, see our guide on selling a house on contaminated land.

How to answer the contamination questions

The golden rule is to be honest and specific. Vague answers create suspicion, blank answers trigger enquiries, and inaccurate answers expose you to legal claims. Here is how to approach each scenario:

If you know the land was previously used for industrial purposes

State what the previous use was, when it ceased (if you know), and whether any remediation was carried out. If you have reports, certificates, or correspondence relating to the contamination or clean-up, provide copies to your solicitor. A typical answer might read: "The property was built on the site of a former engineering works that operated until 1985. The land was remediated by [developer name] before residential development in 1998. A validation report was produced; a copy is attached."

If you have received a notice from the local authority

Disclose the notice in full. Provide a copy and explain its current status. If the notice relates to a Part 2A investigation that is ongoing, say so. If a remediation notice has been served and complied with, attach evidence of compliance. Do not attempt to downplay a formal notice — the buyer's solicitor will discover it through the local authority search (CON29R) in any event.

If you suspect contamination but have no confirmation

If you have reasonable grounds to suspect contamination — for example, you have seen old maps showing a former factory on the site, or neighbours have mentioned historical industrial use — say so. Phrase your answer honestly: "I am aware from historical Ordnance Survey maps that the site was occupied by [use] prior to residential development. I have no information about any contamination assessment or remediation." Using "Not known" is appropriate where you have no information at all, but if you have partial knowledge, share it.

If you are genuinely unaware of any contamination

Answer "No" or "Not to my knowledge." You are not expected to commission investigations to answer the TA6. The obligation is to disclose what you know or ought reasonably to know, not to guarantee the land is clean. However, if you have lived in the area for many years and are aware of its industrial history, the "ought reasonably to know" standard means you should mention it.

Common mistakes sellers make

Contamination questions on the TA6 trip sellers up for several recurring reasons. Understanding these common TA6 mistakes helps you avoid them:

1. Leaving Section 7 blank. An unanswered question forces the buyer's solicitor to raise an additional enquiry, adding days or weeks to the timeline. It also signals that you may be avoiding the question, which erodes trust. Always write something — even "Not known" with a brief explanation.
2. Answering "No" when the correct answer is "Not known." There is a significant legal difference. "No" means you are positively stating there is no contamination. "Not known" means you have no information one way or the other. If you have not investigated and have no specific knowledge, "Not known" is the safer and more accurate response.
3. Failing to disclose known previous industrial use. Even if you believe the land was remediated before your property was built, you should disclose the former use if you are aware of it. The buyer's environmental search will reveal historical land use through Ordnance Survey maps dating back to the 1840s, so any discrepancy between your TA6 and the search results will be noticed immediately.
4. Not providing supporting documents. If you have contamination reports, remediation certificates, environmental insurance policies, or correspondence with the local authority, attach them. Bare answers without evidence prompt follow-up enquiries. Complete answers with documentation resolve questions in a single round.
5. Confusing the TA6 with a technical contamination assessment. You are not being asked to carry out a scientific investigation. You are being asked to state what you know. Answer in plain English, provide documents where available, and let the experts interpret the technical details.

Your legal duty of disclosure

The information you provide on the TA6 is legally significant. Under the Misrepresentation Act 1967, if a buyer relies on a false or misleading statement in the TA6 and suffers a loss as a result, they can bring a claim against you for damages or seek to have the sale rescinded. There are three categories of misrepresentation:

• Fraudulent misrepresentation — You deliberately lied or concealed information. The buyer can claim all consequential losses.
• Negligent misrepresentation — You were careless with your answers and failed to take reasonable steps to check accuracy. Damages are available under the 1967 Act.
• Innocent misrepresentation — You genuinely believed your answer was correct. The buyer may still be able to rescind the contract.

The Consumer Protection from Unfair Trading Regulations 2008 (CPRs) add a further layer. While they primarily target estate agents and property professionals, they reinforce the principle that material information must not be concealed from buyers. For more detail on your obligations, see our guide on the seller's duty of disclosure.

The practical takeaway is straightforward: honest disclosure on the TA6 is your best legal protection. If a buyer later discovers contamination that you knew about and failed to mention, the costs of defending or settling a misrepresentation claim will far exceed any short-term benefit of concealment.

What happens when contamination is flagged during the sale

Even if your TA6 answers are thorough, contamination may be flagged independently by the buyer's searches. This typically happens through two routes:

The environmental search

The buyer's solicitor will order an environmental search from a provider such as Landmark Information Group or Groundsure. This search checks the property against databases held by the Environment Agency, the British Geological Survey, and other bodies. It flags historical industrial use, proximity to landfill sites, pollution incidents, and whether the land appears on the contaminated land register. A "fail" or "further action" result on the contaminated land category will trigger enquiries directed at you.

The local authority search

The CON29R local authority search includes questions about whether the property has been formally determined as contaminated under Part 2A, whether a remediation notice has been served, and whether the land is on the public contaminated land register. If the local authority has investigated the land or is consulting on potential contamination, this will appear in the search results.

How the process unfolds

When contamination is flagged, the buyer's solicitor will raise additional enquiries. You will typically be asked to:

• Confirm or clarify what you disclosed on the TA6
• Provide any contamination reports, remediation certificates, or correspondence you hold
• Explain what, if any, remediation has been carried out and by whom
• Confirm whether you have environmental insurance in place

If your TA6 was completed honestly and your answers are consistent with the search findings, these enquiries can often be resolved in a single exchange. If your TA6 contradicts the search results, the buyer's solicitor will probe further, the buyer will lose confidence, and the sale may be at risk.

Gathering evidence before you list

The most effective way to manage contaminated land questions is to gather your evidence before you market the property. This avoids the reactive scramble that delays so many sales. Consider the following steps:

1. Check historical maps. Review Ordnance Survey historical maps through the National Library of Scotland's map viewer (maps.nls.uk), which covers England and Wales and shows land use from the 1840s onwards. This tells you what was on your site before it became residential.
2. Contact your local authority. Ask the environmental health or environmental protection team whether your property appears on the contaminated land register or has been the subject of any Part 2A investigation. This is public information.
3. Locate existing reports. If the property was developed on a brownfield site, the developer may have commissioned contamination assessments and carried out remediation. Check your purchase file for reports, validation certificates, or references to environmental conditions in your transfer deed.
4. Commission a Phase 1 desk study if appropriate. If historical maps or local knowledge suggest a contaminating former use, a Phase 1 report from a qualified environmental consultant provides an independent risk assessment. This costs between £500 and £1,500 and can pre-empt many of the enquiries the buyer's solicitor would raise. Having the report ready shows you are being transparent and proactive.
5. Consider environmental insurance. Where contamination has been identified but full remediation is impractical or disproportionately expensive, environmental insurance can cover the cost of future remediation and third-party claims. Many mortgage lenders accept such insurance as sufficient protection. Premiums are typically a one-off payment of £500 to £5,000 depending on the risk level.

Taking these steps before listing means that when the buyer's solicitor raises contamination enquiries, your solicitor can respond immediately with a complete information pack rather than chasing documents while the clock ticks. For more on preparing your legal paperwork early, see our property information form tips.

Contamination and mortgage lenders

The buyer's mortgage lender will assess contaminated land risk as part of its lending decision. Properties flagged on the environmental search or the contaminated land register receive additional scrutiny from the lender's valuer and risk team. Common outcomes include:

As the seller, you cannot control which lender the buyer uses, but you can make it easier for them to secure approval by providing a complete, transparent picture of the contamination position. A buyer who can hand their lender a Phase 1 report and environmental insurance policy alongside their mortgage application is far more likely to receive a timely offer.

Liability under Part 2A: what sellers need to know

Part 2A of the Environmental Protection Act 1990 follows the polluter pays principle. When a local authority determines that land is contaminated, it must identify the "appropriate person" responsible for remediation:

• Class A — The person who caused or knowingly permitted the contamination. This is the primary liability category. If you operated the polluting activity, you remain liable even after selling.
• Class B — The current owner or occupier. This fallback category applies only when no Class A person can be found. If you are an innocent owner, your Class B liability typically passes to the buyer on completion of the sale.

Selling a contaminated property does not automatically extinguish your liability. If you caused the contamination, you may remain a Class A appropriate person even after the sale. The statutory guidance (DEFRA, 2012) includes exclusion tests that can remove parties from liability in certain circumstances — for example, where the seller disclosed the contamination and sold at a reduced price. These tests are highly fact-specific, and your solicitor should advise on your individual position.

Honest disclosure on the TA6 is directly relevant to these exclusion tests. A seller who fully disclosed the contamination issue, provided reports, and sold at a price reflecting the risk is in a much stronger position to argue for exclusion from liability than one who concealed the problem.

Practical examples

To illustrate how these principles work in practice, here are three common scenarios:

Scenario 1: Property built on a former factory site

You purchased a house built in 2002 on the site of a former engineering works. The developer carried out remediation before construction and a validation report was produced. On your TA6, you should state the previous use, confirm that remediation was carried out, and attach the validation report. If you no longer have the report, contact the developer or your local authority's building control department, who may hold a copy.

Scenario 2: Property near a closed landfill

Your property is within 250 metres of a former landfill that closed in the 1990s. You have not experienced any problems, but you are aware of the landfill from local knowledge. On the TA6, note that you are aware of the nearby closed landfill and state that you have not experienced any related issues (odour, ground gas, water contamination). The environmental search will flag the landfill independently, so consistency between your answer and the search results is important.

Scenario 3: No known contamination history

You live in a suburban area with no obvious industrial history and have never received any notice from the local authority about contamination. You can answer "No" or "Not to my knowledge" to the contamination questions. This is straightforward, but check historical maps as a precaution —many suburban areas were built on land that had previous uses you might not be aware of.

Getting ahead with Pine

Contamination questions on the TA6 cause the most difficulty when sellers are forced to deal with them reactively — answering enquiries under time pressure after the buyer's searches have flagged an issue. By then, every day of delay increases the risk of the sale falling through.

Pine helps sellers complete their TA6 Property Information Form before listing, with built-in guidance on how to answer each section, including the environmental matters questions in Section 7. By gathering evidence, commissioning reports where necessary, and preparing honest, thorough answers before your buyer arrives, you create a legal pack that builds confidence and keeps the conveyancing process moving.

Sources

• Law Society of England and Wales — Property Information Form (TA6), 4th edition, 2020
• Environmental Protection Act 1990, Part 2A (sections 78A–78YC)— legislation.gov.uk
• DEFRA — Contaminated Land Statutory Guidance, April 2012 — gov.uk/government/publications/contaminated-land-statutory-guidance
• Environment Agency — Land contamination: risk management — gov.uk/guidance/land-contamination-how-to-manage-the-risks
• Misrepresentation Act 1967 — legislation.gov.uk
• Consumer Protection from Unfair Trading Regulations 2008 — legislation.gov.uk
• RICS — Contamination, the Environment and Sustainability, 3rd edition — rics.org
• HM Government — Contaminated land guidance for local authorities — gov.uk/guidance/contaminated-land
• National Library of Scotland — Historical Ordnance Survey maps— maps.nls.uk

Related guides

• TA6 Japanese Knotweed: What to Disclose

Frequently asked questions