On 20 March 2012, SEPA published the new edition of Water Pollution Arising from Land Containing Chemical Contaminants. Commonly known as the Brown Booklet, this is SEPA's guidance on how they assess whether significant pollution of the water environment in Scotland is being caused, or there is a significant possibility of such pollution being caused. It replaces the previous edition, published in 2001, and Interim Advice on the Measures of Significant Pollution, published in 2006.
The Brown Booklet will primarily be of assistance in the contaminated land regime under Part IIA of the Environmental Protection Act 1990 (the 1990 Act) and the planning regime but will also be useful for other regimes which place controls on contaminated land, such as the PPC permit regime and the CAR licence regime.
It will also play a part in achieving aims of the Water Framework Directive to prevent deterioration and protect and enhance the status of aquatic ecosystems and to reduce pollution. These aims are to be achieved through the River Basin Management Planning process which will seek to achieve these environmental objectives through existing regulatory regimes.
There will be three stages to SEPA's assessment of water pollution:
SEPA considers pollution to be significant where contamination is entering or is likely to enter the water environment at a level in excess of an assessment limit at an appropriate assessment point. However, SEPA accepts that specific sites may present anomalies and emphasises the importance of local authorities obtaining site specific advice. Where the stage 3 assessment demonstrates that there is not, or will not be, a breach of, or failure to meet, an assessment limit for a receptor, SEPA suggests that it is not then possible that the pollution would be assessed as significant.
When determining the seriousness of the pollution and the level of remediation required, consideration will be given to the impacts of the pollution on legitimate uses of the water environment. The ultimate aim of any remediation should be to ensure that significant pollution of the water environment is no longer occurring, or is not likely to occur, and to remedy any effects of pollution that have already occurred. However, the Brown Booklet acknowledges other controls which may limit the remediation that can be required.
Under Part IIA of the 1990 Act, the standard of remediation that can be required will depend on what is reasonable, having regard to factors such as likely cost, the benefits that would be achieved and the seriousness of the pollution. Additionally, although Article 6 of the Groundwater Directive (2006/118/EC) contains a general requirement to ensure that all measures necessary are taken to prevent inputs into groundwater of any hazardous substances, there are a number of exceptions to this general requirement, e.g. where the input is incapable, for technical reasons, of being prevented or limited without using disproportionately costly measures or measures that would increase risks to human health or the quality of the environment as a whole.