Geoscientist Online

Charlene Knox FGS, Senior Engineer at Card Geotechnics Ltd., reviews the recently reviewed Statutory Guidance on Contaminated Land under Part 2A of the Environmental Protection Act 1990.

Geoscientist Online 12 June 2012

We hear that the UK is currently in recession - its second since 2008. While it has struck business leaders and government officials alike that growth must be firmly on the agenda, ‘deficit reduction’ and ‘austerity’ are still playing major parts in government policies worldwide.

For the past four years, there has been no escaping the ‘belt-tightening’ and the contaminated land industry is no exception. We have had ‘the cull of the QUANGOs’, restructuring of environmental organisations, and budget cuts for local authorities; and significantly, the withdrawal and overhaul of guidance documents that have been integral to the industry. While there has been no change to the fundamental contaminated land legislation, one such recent change has been to the Statutory Guidance on Contaminated Land under Part 2A of the Environmental Protection Act 1990.

The consultation and revisions of the 2006 guidance, led by Defra, led to the revised document being presented to Parliament in February. It has been in force as statutory guidance since April this year. The main motivation for the revision was to address inconsistencies and ambiguities in the original document. Those of us working in the industry know that these have led to unnecessary remediation of certain sites, causing a financial ‘domino-effect’, from developers to the construction industry and ultimately, the UK economy.

UNACCEPTABLE CONTAMINATION

The intention behind the update was to make the guidance more usable; to clarify when land may legally be defined as ‘contaminated’ and, hence, whether it requires remediation. The best way to achieve this was to be more explicit about what actually constitutes ‘unacceptable contamination’. Therefore, a new four-point test has been introduced to determine the contamination status of sites, and to clarify the standing of screening values, such as the Environment Agency’s Soil Guideline Values (SGVs) and industry-determined Generic Assessment Criteria (GACs). In the past, these have commonly been misused as ‘clean up’ standards; but they are actually below the threshold for planning (a much more rigorous test) and therefore, are far more conservative than any remediation criteria. The updated guidance is very useful in addressing the fact that many sites are ‘low risk’ in reality, and few will meet the legal definition of ‘contaminated land’.

SPOSH

Naturally occurring background concentrations of potential ‘contaminants’ have also been recognised - an important step in avoiding needless and costly remediation. In addition, Defra is now developing Category 4 Screening Levels (the new generic assessment ‘numbers’) to help Local Authorities recognise sites that definitely do not present a Significant Possibility of Significant Harm (SPOSH). It is hoped that this will help to reduce uncertainty and bring a more holistic and pragmatic approach to ensuring that sites nationwide are dealt with in a consistent way.

So it could well be that we finally have a set of documents that provides clear and unequivocal guidance as to when land is ‘contaminated’ and so gives a clear steer as to when remediation may be required. More work is necessary to flesh out the guidance, providing Category 4 Screening Levels and establishing background concentrations of potential contaminants. However, this first step in the right direction should be welcomed for reducing the burden on the land development industry and helping to prevent the unnecessary remediation of marginal land.

• Read previous opinion piece on the shortcomings of SPOSH 
• Card Geotechnics Ltd

Charlene Knox FGS is a Senior Engineer with Card Geotechnics Limited.