Contaminated land: the suitably qualified person test

Councils expect land contamination reports to be prepared in accordance with BS 10175 by suitably qualified and experienced persons, and that phrase carries more weight than it looks. It is the reason a Phase 1 desk study written by a generalist gets returned, the reason a contamination condition stays undischarged while a sale falls through, and the reason the Land Contamination Phase 1 and Phase 2 reports are two of the report types where a qualified professional is legally expected rather than merely preferred.

For anyone converting a former workshop, garage forecourt, print works or light industrial unit into flats, the competence of the author is the part of the process most worth getting right first time.

What national policy expects of the author

The National Planning Policy Framework places responsibility for securing a safe development on the developer and the landowner. The planning system's job is to be satisfied that the site is suitable for its proposed use, taking account of ground conditions, including contamination, and of any risks to health, property and the water environment.

That produces a specific evidential burden. The authority has to be satisfied, on the information before it, that the site can be made suitable. An author who cannot demonstrate the competence to reach the conclusions in the report gives the authority no basis to be satisfied, whatever the report says.

The environmental regulator's land contamination risk management guidance sets out the process the authority expects to see followed: risk assessment, options appraisal, then remediation and verification, each stage building on the conceptual site model. The guidance assumes competent people at each stage.

Note that the planning route is separate from the contaminated land regime under Part IIA of the Environmental Protection Act 1990. Part IIA deals with land already determined as contaminated and is triggered rarely. Almost everything a landlord or converter meets will run through planning conditions.

What BS 10175 assumes about competence

BS 10175, the code of practice for the investigation of potentially contaminated sites, is written on the assumption that the work is carried out by or under the direction of suitably qualified and experienced persons. It does not set out a single qualification, and that is the source of the confusion.

In practice competence is demonstrated by a combination of three things.

• A relevant chartered status, for example chartered geologist, chartered environmentalist, chartered scientist or chartered engineer, held by the individual who directs the work and signs the report.
• Membership of a recognised competence register for land condition, or accreditation as a suitably qualified person under the national quality mark arrangements for land contamination reports.
• Demonstrable project experience on sites with comparable former uses, contaminants and receptors.

Ask for all three. A firm with a strong reputation and no named individual carrying competence for your site type is a risk, because it is the individual who signs and the individual whose judgement the officer is relying on.

Laboratory competence is a separate question and is often overlooked. Analysis should be by a laboratory holding accreditation for the specific determinands in the specific matrix, and the report should say so. A Phase 2 with unaccredited analysis of soils will be queried.

Who does what at each stage

The stages are not interchangeable, and neither are the people.

1. Phase 1 desk study and preliminary risk assessment. Historical map regression, regulatory enquiries, a walkover and a conceptual site model setting out sources, pathways and receptors. Directed by an experienced contaminated land specialist. This is the stage most often written badly, usually by someone who has produced a data pack rather than a risk assessment.
2. Phase 2 intrusive investigation. Designed by the specialist to test the hypotheses in the conceptual site model, with a sampling strategy, health and safety planning, accredited analysis and generic or detailed quantitative risk assessment.
3. Options appraisal and remediation strategy. Chosen by someone who understands both the risk and the buildability of the options, working with the ground engineer and the designer.
4. Implementation and verification. Supervised on site, with sampling as the works proceed rather than afterwards.

A contaminated land assessment drafted with AI assistance can give you the structure, the conceptual site model headings and the regulatory framework. It is a starting point for the qualified specialist who directs the investigation and signs the conclusions, and nothing in it substitutes for their judgement or for intrusive work on the ground.

Signing a verification report

The verification report is the document that closes the condition, and the signature on it matters more than on any other stage. It has to show what was found, what was done, and that what was done achieved the remediation objectives.

The person signing should be the one who directed the verification sampling, hold the competence described above, and be independent enough to be credible. Where the remediation contractor also writes the verification report, expect the authority to look harder, and expect a purchaser's solicitor to do the same. Some authorities will not accept it at all.

Materials that are re-used on site rather than sent to landfill need their own documentary trail, prepared under a recognised code of practice for the definition of waste, and that trail belongs in the verification pack rather than in a contractor's file.

Evidence a council asks for

Contaminated land officers and environmental health officers ask for a consistent set of things. Have them ready.

The author's name, qualifications and role, stated in the report rather than in a covering email. The competence basis, whether that is chartered status, register membership or scheme accreditation. The laboratory's accreditation schedule for the determinands reported. The conceptual site model, updated at each stage rather than copied from Phase 1. Raw laboratory certificates as an appendix, not just summary tables. The assessment criteria used and their source, with the reasoning where site-specific values have been derived.

Two habits save weeks. Submit the Phase 1 with the application rather than relying on a condition, because a desk study that identifies a plausible pollutant linkage changes the wording of the condition and sometimes the layout. And ask the officer, before the intrusive work, whether the proposed sampling strategy is acceptable in principle.

Our note on writing a brief for a specialist report covers how to set the scope so that the output answers the condition rather than a general question.

Where an unqualified report stalls a condition

The commercial damage comes from sequencing. A typical contamination condition has four limbs: site investigation, remediation scheme, implementation and verification, and reporting of unexpected contamination. The first three are commonly pre-commencement, and verification is usually tied to occupation.

An inadequate Phase 1 means the authority cannot agree the investigation scope, which delays the intrusive work, which delays the remediation scheme, which delays commencement. A verification report the officer will not accept sits between practical completion and lawful occupation, which is the worst place for a delay to land. Lenders and purchasers' solicitors will not complete against an undischarged contamination condition on a residential conversion, and the argument is rarely worth having.

If you have inherited a report you did not commission, have it reviewed before you rely on it. Our note on reviewing a specialist report you did not commission sets out what to check.

The professional review route matters here too. A draft that has been reviewed and signed off by an appropriately qualified reviewer through the professional directory is a different proposition from an unsigned document, both for the case officer and for the person buying the flat in three years.

Records the next owner will need

Keep the whole chain: Phase 1, Phase 2 with laboratory certificates, the remediation strategy, the verification report, the materials documentation, the discharge of conditions decision notice and the correspondence agreeing the approach. Scan it, keep it in one place, and hand it over on sale.

The reason is practical. A future purchaser's environmental search will flag the former use whatever you have done. The verification pack is the answer to that flag. Without it, the next buyer commissions their own desk study, discovers a historical use with no evidence of remediation, and reprices.

This is general guidance, not legal advice. Land contamination reports must be prepared by suitably qualified and experienced persons, and for specialist technical reports qualified professional input may be required. Check the position with your local planning authority before relying on anything here. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.

Browse all 66 PlanScope report types to see where the contamination reports sit in a conversion pack.