Screening and Mitigation Measures – Environmental Impact Assessment

A recent decision of the Court of Justice of the European Union (CJEU) will have implications for all nationally significant infrastructure and other projects that could affect protected environmental sites with the special EU level of protection known collectively as Natura 2000 sites, or sometimes by some of their sub-types, Special Protection Areas and Special Areas of Conservation. 

The case, known as ‘People Over Wind v Coillte Teoranta’, concerned an electricity cable to connect a wind farm, and its potential to affect two SACs, one of which contains a species of mussel (the Nore pearl mussel) that is at risk of becoming extinct. 

By way of a quick precis, the mussels need clear water and so the deposit of any sediment would be an issue. The developers obtained a screening opinion that this would not be a problem if specified ‘protective measures’ were implemented, set out in a Construction Environmental Management Plan (CEMP). The screening meant that the project did not need to go further along the process of analysing effects on the SPAs known as ‘appropriate assessment’.

The High Court of Ireland referred the following question to the CJEU: “Whether, or in what circumstances, mitigation measures can be considered when carrying out screening for appropriate assessment under Article 6(3) of the Habitats Directive?”

The CJEU answered bluntly that “in order to determine whether it is necessary to carry out, subsequently, an appropriate assessment of the implications, for a site concerned, of a plan or project, it is not appropriate, at the screening stage, to take account of the measures intended to avoid or reduce the harmful effects of the plan or project on that site.”

The main reason given was that a full and precise analysis of the measures capable of avoiding or reducing any significant effects on the site concerned must be carried out not at the screening stage, but specifically at the stage of the appropriate assessment. 

This decision is at odds with a 2008 English case Hart v Secretary of State for Communities and Local Government, where Mr Justice Sullivan said that “I am satisfied that there is no legal requirement that a screening assessment under Regulation 48(1) must be carried out in the absence of any mitigation measures that form part of a plan or project.”

So where does that leave us? Although it doesn’t necessarily mean projects being more likely to be refused, it does mean they may have to go further along the appropriate assessment flowchart before they can get consent

A copy of the judgment can be found here