Environmental Impact Assessment

Particularly outline planning applications have been the subject of much EIA case law in recent years and the lessons from these cases have been applied to this EIA. The "Tew" and "Milne" cases (also known as the "Rochdale" cases) have provided some clarification, particularly on the level of information required to describe the proposed development. The key conclusions are that outline applications with only illustrative details of the development are unlikely to comply with the EIA Regulations 1999 and that a clear link (usually by condition) must be drawn between the consent and information supplied. This does not mean that there is no flexibility, but development must be within the remit of the outline permission.

In 2006, the House of Lords and the European Court of Justice (ECJ) ruled that the UK had failed to transpose the EIA Directive correctly, because the regulations implementing the EIA Directive allowed only for EIA before the grant of outline planning permission and not at the later stage when reserved matters were approved. The ECJ ruled that where development cannot be carried out until details relating to reserved matters are approved by a local planning authority, the decisions to grant outline planning permission and to approve the reserved matters must be considered to constitute, as a whole, a multi-stage development consent for the purposes of the EIA Directive. If it became apparent during the course of the second stage that the project was likely to have significant effects on the environment (for example, where those effects were not identifiable until then) then an environmental impact assessment was required. Since the regulations then in force did not allow for EIA to be required at that stage, they did not fully implement the EIA Directive. The EIA regulations were amended in 2008 to address this non-compliance.

By attaching planning condition to the permission for outline planning applications that reflect the development as assessed through the EIA process, planning authorities can ensure an understanding of the significance of the effects that will arise and how these should be mitigated. When a reserved matter applications departs from the established position, a planning authority can decide whether this materially affects the findings of the EIA and, therefore, whether supplementary environmental information, possibly even another EIA (see the "Barker" case), is required.