The majority of modern environmental legislation in the UK is derived from EU law, either from directives that have been implemented by UK domestic legislation or from regulations that apply directly in EU member states such as the UK. With the advent of the UK’s withdrawal from the EU following the referendum held last June, the question has arisen as to the effect of “Brexit” on UK environmental law. There is little clarity on this question now, as the UK government has yet to unveil its strategy on how and when it will implement Brexit. It remains unclear whether the UK government will seek to adopt an already-established model of being outside of but closely linked to the EU – for example, that of non-EU states that are part of the European Economic Area (EEA) such as Iceland, Liechtenstein and Norway, or that of European Free Trade Association (EFTA) states that are not EU or EEA members but gain market access to the EU primarily through bilateral agreements, such as Switzerland – or a wholly bespoke arrangement. In practice, any approach that is bilateral – and a complete severance of ties seems unlikely – will also require the consent of, and therefore be shaped by, EU member states. Perhaps because of this and also to some extent because of geographic proximity and common trans-boundary concerns, it seems likely that EU environmental law will remain relevant to the development of UK environmental law and policy.

As a starting point, the referendum itself has no legal effect on the laws of the UK or EU. The UK will remain a member of the EU until there is either an agreement to exit or expiration of a two-year period after a formal notice of exit is issued by the UK government. This notice, when served, triggers a negotiation period of up to two years during which time the current EU laws continue to apply in the UK. The UK government has not yet issued this notice.

During the transitional period that ensues, the UK government will need to conduct a complex review of what existing environmental legislation derived from the EU should continue to apply, including where the legislation is directly set out in EU text, taking the necessary steps to adopt domestic legislation for its implementation. Such a review will naturally be guided by the broader thinking on the UK-EU relationship after Brexit is implemented. If the UK opts to remain in the EEA as a non-EU state, “Norwegian” style, it will be required to formally continue to adopt most EU environmental legislation, including in areas such as environmental permitting, air and water quality, greenhouse gas emissions, waste, electrical and electronic equipment and chemicals registration.

Under a bilateral agreement model or bespoke arrangement, more freedom would be afforded to the UK to set its own course regarding operational environmental controls within its own borders. For example, Switzerland is not required to comply with EU environmental legislation by virtue of its EFTA membership only. In practice, Switzerland has put in place bilateral agreements with the EU to gain access to the EU single market, which in turn have resulted in the country harmonizing much of its environmental legislation with that of the EU.

As with any country outside European institutions altogether, the UK would still be required to meet EU environmental and safety standards regarding products being placed onto the EU market. For example, the sweeping EU law governing the registration and safety analysis of chemicals, known by its acronym REACH, requires chemical manufacturers in the rest of the world wishing to sell their products into the EU to appoint an “EU Only” Representative that ensures REACH compliance. In addition, certain environmental laws govern inherently trans-border or regional concerns, such as those dealing with global greenhouse gas emissions reduction and control (Kyoto Protocol) or marine pollution (the OSPAR Convention). There is no indication that the UK government would push back strongly on its existing commitments under these laws.

Over the last 25 years, the UK has been at the forefront of certain environmental protection legislation, and some prominent UK domestic legislation does not derive from the EU. Two notable examples are the UK’s contaminated land regime, which established in the UK a “polluter pays” principle for cleanup of soil and groundwater contamination before similar legislation was introduced at EU level, and the Climate Change Act of 2008, which established very ambitious targets to reduce greenhouse gas emissions domestically by 80% from 1990 levels by 2050. It is not likely that Brexit would trigger major changes in these areas.