Unicoin (Dartford) Ltd, R (on the application of) v Secretary of State for Communities and Local Government & Anor

The claimant sought judicial review under section 288 of the Town and Country Planning Act 1990 of an Inspector's decision dismissing an appeal for planning permission for residential development near a hazardous installation. The key legal principles were that the court's remit is limited to the grounds in section 288 and to considering the case as it was presented to the Inspector, and that Circular 04/00 and HSE's PADHI methodology guide assessment of residual risk from hazardous substances. The court rejected the claimant's argument that the Inspector was bound to apply a separate "tolerability" test from paragraph 41 of Circular 04/00 and also rejected the contention that the Inspector was required to base her assessment on the operator's Regulation 6 COMAH notification rather than the envelope approach used by HSE to reflect deemed hazardous substances consents. The court held that the Inspector lawfully weighed the HSE's PADHI-based evidence, properly considered the COMAH controls and their limits, and gave adequate reasons for concluding that the proposal would unacceptably increase the number of people exposed to residual risk. The application was dismissed.

The claimant owned land formerly part of an effluent treatment works and sought permission to build 96 dwellings; the local planning authority refused on a single ground: that a substantial part of the site lay in the HSE's Inner Consultation Zone around a neighbouring GlaxoSmithKline hazardous installation and the development would expose more people to residual risk. The claimant appealed; the Inspector, relying on HSE evidence using its PADHI land-use planning methodology and the envelope of risk derived from broad deemed hazardous substances consents, dismissed the appeal.

The claimant sought judicial review under s.288 alleging (i) that the Inspector failed to apply the correct test (arguing that the "tolerability" test in paragraph 41 of Circular 04/00 should apply), (ii) that the Inspector should have based risk assessment on the specific inventories notified under Regulation 6 of the COMAH Regulations rather than the exemplar/envelope approach, (iii) that the Inspector undervalued COMAH and Health and Safety at Work Act controls and failed to assume compliance with reasonably practicable measures, and (iv) that the Inspector erred in concluding additional residents could not be tolerated where existing residents were accepted as tolerable.

The court analysed Circular 04/00, the PADHI approach, the COMAH Regulations (including Regulations 6 and 7 and Schedules 3 and 4) and the evidence before the Inspector. It concluded: the tolerability test in paragraph 41 applies to hazardous substances consent decisions and could not be read across to development control in the way the claimant urged; the Inspector was entitled to rely on HSE's envelope approach when the hazardous substances consent was expressed in broad terms; the Inspector lawfully considered COMAH controls but reasonably gave them limited weight in assessing residual off-site risk; and the Inspector provided adequate reasons for concluding the proposed development would unacceptably increase the number of people exposed to residual risk. The application was dismissed, costs were awarded to the Secretary of State, and permission to appeal was refused but time to seek permission in the Court of Appeal was extended to 14 days after release of the transcript.

The application is dismissed. The court held that the Inspector lawfully and rationally applied Circular 04/00 and HSE's PADHI methodology, was entitled to base her assessment on the envelope of risk arising from broad hazardous substances consents rather than solely on a single Regulation 6 notification, properly assessed the limited weight to be given to COMAH controls in relation to residual off-site risk, and gave adequate reasons for concluding the proposed development would unacceptably increase the number of people exposed to residual risk.