Thomas v Carmarthenshire Council

A planning authority must decide whether a proposal falls within the environmental impact assessment regime and, where appropriate, undertake screening. The relevant question is whether the project is likely to have significant effects on the environment. A precautionary approach is required, but remedial or ameliorative measures may be taken into account where their effectiveness can reasonably be predicted. A planning condition should not create uncertainty or appear to bypass the statutory process for a material change of use. An unlawful or unnecessary part of a condition may be severed without invalidating the whole permission. A legitimate expectation normally requires the authority to take objections into account; it does not necessarily require adoption of a particular drainage solution.

The claimant, the owner and occupier of land adjoining a former colliery site, challenged retrospective planning permission granted by Carmarthenshire Council to Davis Coaches Ltd for a coach depot and associated buildings. The challenge concerned environmental impact assessment, enforcement, the lawfulness of planning conditions, consultation, and an alleged legitimate expectation concerning surface-water drainage.

The enforcement ground was abandoned. The central questions were whether an environmental impact assessment screening decision was required, whether the conditions unlawfully bypassed the planning process or required prior consultation, and whether the drainage condition frustrated a legally enforceable legitimate expectation.

1. Environmental impact assessment. The authority was entitled to treat the permitted Area 6 as no more than 0.46 hectares, below the 0.5-hectare threshold applicable to the relevant Schedule 2 categories. The wider colliery site was relevant to the separate question of an extension under paragraph 13 of Schedule 2.
2. Area 6 was properly regarded as an extension of development already authorised or executed on the wider site. The authority nevertheless lawfully concluded that the development, considered with the conditions and section 106 agreement, was not likely to have significant adverse environmental effects. The authority could take account of drainage improvements and other ameliorative measures. Its decision was reviewable on Wednesbury principles, subject to the precautionary principle and the degree of uncertainty at the decision date.
3. Consultation. No additional duty to consult the claimant before imposing landscaping, petrol-interceptor and surface-water conditions was established by the Aarhus Convention. The claimant’s objections had been considered, the Environment Agency had been involved, and further consultation would not have given her a veto.
4. Condition 3(ii). A condition prohibiting any extension or intensification without the authority’s written approval risked uncertainty and could appear to permit evasion of the statutory process required for a material change of use. Following the approach in Mid Counties Cooperative Ltd v Wyre Forest DC and Warley v Wealden DC, the court severed the condition by deleting it. The remainder of the permission remained valid.
5. Legitimate expectation. The claimant’s expectation was limited to her complaints and objections being taken into account and lawful steps being adopted. The authority was entitled to require monitoring and to make further works conditional upon the monitoring results. Condition 3(vi) was therefore neither unlawful nor unreasonable.
6. The application was refused save for the excision of condition 3(ii). The defendant’s costs were capped at £5,000; the judgment’s costs discussion concerning the interested party was left incomplete.

The judgment records an earlier enforcement appeal before a planning inspector. The appeal succeeded only to the extent of extending the compliance period, and the enforcement notice was upheld. Retrospective planning permission was subsequently granted and was challenged in this judicial review.