Together Against Sizewell C Limited, R (on the application of) v Secretary of State for Energy Security and Net Zero

In deciding whether development is one “project” for environmental assessment, the decision-maker may weigh functional interdependence, ownership, the scope of the application, the timing of related statutory processes and whether each element is standalone. The judgment is reviewable only on Wednesbury principles. Separate projects may have their cumulative effects assessed at a later consent stage where their details are not yet known, provided the approach does not evade environmental assessment through salami-slicing.

Under regulation 64(1) of the Conservation of Habitats and Species Regulations 2017, alternative solutions must meet genuine and critical core policy objectives. An option is not excluded merely because it meets those objectives less fully. Expert consultees may be disagreed with where reasons are adequate in context. Ministers may rely on accurate summaries, and future technical risks may be managed through adaptive design and regulation.

Together Against Sizewell C Limited sought judicial review under section 118(1) of the Planning Act 2008 of the Secretary of State’s decision to make the Sizewell C (Nuclear Generating Station) Order 2022. The Order granted development consent for a nuclear power station.

The examining Panel had considered that the case for consent was not made out because no permanent potable water supply had been identified. The Secretary of State concluded that the supply was a separate project, that its environmental effects would be assessed through later regulatory processes, and that consent could be granted.

The claimant advanced seven grounds concerning project scope, cumulative effects, reasons for departing from Natural England’s advice, alternative solutions, greenhouse-gas benefits, radioactive waste and operational emissions. The central issues were whether the permanent water supply formed part of the project or had to be assessed cumulatively before consent was granted, and whether the Secretary of State’s conclusions were irrational or inadequately reasoned.

1. Disposition. All seven grounds were rejected. Grounds 1 and 2 were unarguable. Grounds 3 to 7 were totally without merit. Permission to apply for judicial review was refused and the application was dismissed.
2. Project scope and cumulative effects. Neither the Habitats Regulations nor the EIA Regulations defined “project”. Its scope was a matter for the Secretary of State’s judgment, reviewable only on Wednesbury principles. Relevant factors included ownership, simultaneous determination, functional interdependence and whether development was standalone. The factors were non-exhaustive and their weight depended on the circumstances. The court had to guard against salami-slicing, but separate projects could properly be brought forward at different times. Their cumulative effects could be assessed at a later stage where the later project was inchoate and its details were unknown.
3. The Secretary of State was entitled to treat Sizewell C and the permanent water supply as separate projects. Northumbrian Water Limited had an independent statutory duty to prepare its water resources management plan, the processes had separate ownership and were asynchronous, and no particular permanent supply had been identified. The claimant had produced no evidence establishing functional interdependence in the relevant sense. A later environmental assessment was not invalid merely because the power station depended on some future supply. A hypothetical permanent desalination plant did not require assessment as part of the present application.
4. The decision to defer assessment of unknown cumulative effects to the water-resources process was rational. A future assessment under the Habitats Regulations would have to apply the IROPI test without distortion. The earlier grant of consent created no presumption that later consent would follow, and the benefits and harms of the projects would both have to be considered.
5. Natural England and reasons. The Secretary of State could disagree with Natural England. The level of explanation required depended on whether the advice was reasoned and supported by evidence, as well as on the subject matter. Natural England’s advice that the water supply was integral and that effects might be missed or downplayed consisted of bare assertions. The decision letter adequately explained the disagreement when read as a whole.
6. Alternative solutions. Regulation 64(1) required consideration of alternatives meeting the genuine and critical objectives of the relevant policy. The objectives included low-carbon generation, diversity of energy sources and security of supply. Alternative technologies were not alternative solutions merely because they could generate comparatively clean electricity. The Secretary of State was entitled to rely on the Government’s policy objectives without treating the NPSs as conclusive.
7. Future risks and emissions. An enhanced margin of appreciation applied to scientific, technical and predictive assessments. The Secretary of State could rely on the proposed adaptive coastal-defence design, monitoring, and the regulatory roles of the ONR and Environment Agency. The assumption that spent fuel would be removed by 2140 was not irrational. The evidence was also sufficient to support the expected contribution to electricity generation and emissions reduction by 2035. There was no inconsistency between deferring assessment of an unknown water supply and relying on the reasonable confidence that a compliant supply would be delivered. The Secretary of State could rely on departmental summaries of the quantitative emissions evidence.

This was a first-instance judicial review claim. On 19 October 2022 Kerr J refused permission on the papers. On 14 December 2022 Holgate J refused permission to add ground 8 and directed that the renewed application on grounds 1 to 7 proceed to a rolled-up hearing. Ground 8 was withdrawn on 10 January 2023. Following the rolled-up hearing, permission was refused and the application dismissed.