More than just green

Restoring contaminated sites can pose risks to human health and the environment. Remediation specialists Rick Parkman and Richard Bewley discuss how sustainable remediation looks at the bigger picture to balance the risks of clean-up with the wider benefits to society.

Sustainability is one of the biggest concerns of our time. Climate change, urbanisation and the increasing pressure on world resources mean reducing our impact on the planet has become important in almost every facet of life, with environmental restoration no exception.

With this in mind, all remediation should be sustainable — the benefits of a clean-up programme should be greater than its impact on the environment and the communities around it. If it’s not, the remediation shouldn’t happen. However, all too often, organisations and their remediation consultants rush into massive clean-up programmes, often creating a huge carbon footprint with little thought of the long-term use of the site or benefits to the wider community.

Managing risk

Remediation best practice addresses these issues by asking — what are the contaminants? What are the receptors? And what are the pathways between them?

Only after understanding these should discussion take place between the client, landowner, consultant and regulator around what the risks are and the level of clean-up required.

Sustainable remediation is part of our strategy to bring a risk management based approach to clean-up, enabling efficiency throughout the entire contaminated land management cycle. For example, on a clay-based site that’s far from rivers and aquifers, there may be much less risk from groundwater contamination than a site on porous ground near a river system, even if the contaminants are similar in both cases.

With sustainable remediation, different levels of clean-up could take place at the two sites. In contrast, a more traditional solution may force both sites to be cleaned to a particular value, even though there is minimal risk of contamination in the former case. By understanding the ‘big picture’ — the overarching objectives of the remediation up‑front — remediators can put an appropriate framework in place.

A balancing act

A sustainable approach brings a range of benefits to a remediation project. In the short term, it helps eliminate unnecessary works by focusing only on the issues driving risk and selecting remedial technologies where the benefits of remediation are greater than its impact. By not having to clean up to unnecessarily onerous targets, remediation can be more efficient and cost-effective. It promotes positive relationships with the stakeholders on a project through engagement with local authorities, neighbours, end users and regulators to gain agreement for the proposed strategy in a robust and transparent procedure that ensures the end result meets all of their requirements.

Community engagement

This takes into account the views of local people and communities living in proximity to the proposed clean-up. For example, nuisance issues relating to noise, dust and odour are factored into the decision-making process with regard to which remedial approach to select, and are addressed during the actual implementation of the remedial works. It also aims to help restore the natural environment to the best possible condition, while minimising the carbon footprint of the works.

Tools for the job

To help optimise sustainable remediation projects, AECOM developed an Excel-based tool that enables our teams to balance economic, social and environmental sustainability criteria and agree a way forward that’s right for each particular site.

The tool recognises that all sites are different. For example, at one site, economic criteria — getting the land back into use — may be the most important driver, justifying extensive removal of contaminated soil. Another site may have similar criteria, but may be close to a residential area. Reducing the impact on that community may be of critical importance, so a less intrusive clean-up may be required. As part of the process, we can determine the relative performance of each option against these key criteria so that the clean-up decisions are supported by sound technical information.

Regulation and negotiation

Sustainable remediation will always be an area of debate. Some commentators may feel that it lets polluters get away with doing the least amount of work possible, shifting responsibility for the clean-up onto the regulator’s shoulders. However, unacceptable risks should always be removed in a sustainable way.

There are precedents in the European Union (EU) in particular, where a range of legislation has come into force to uphold sustainable remediation principles and techniques. In fact, the complexity of the EU’s regulatory regime around sustainability brings its own issues. Clients or even local government teams may be unaware of certain legislation, which may impact discussions that promote sustainability and hamper agreements on an appropriate remedial strategy.

In the long term

At its heart, sustainable remediation is about delivering the best value to landowners, developers, regulators and communities. Our involvement with industry bodies such as the Sustainable Remediation Forum and Network for Industry Contaminated Land in Europe helps us grow and share this knowledge base to deliver efficient, compliant remediation that brings the best long-term benefit to site owners and communities.

Uncomplicating clean-up legislation

The legislative framework for remediation in the UK and EU requires sustainable principles to be included in remediation projects. However, the regulations are often not appreciated or understood by local regulators.

To address this, we worked with oil company Shell and several industry groups to create a user-friendly guide that brings together all of the relevant legislation available to regulators, site owners and consultants, to help make the case for a sustainable remediation approach.

The Shell-funded report correlates all the various clauses within UK and EU policy documents that support sustainable remediation, so that they can be readily brought to bear in discussions or negotiations. It also sets out a number of potential scenarios in which sustainable remediation may be either necessary or desirable and identifies relevant legislation.

The report is designed to aid discussions with our clients and regulatory authorities, helping reassure in-country regulators that they are in compliance, that the client and consultant understand the nature of the problem and that they are managing it sustainably.

The report — A review of the legal and regulatory basis for sustainable remediation in the European Union and the United Kingdom — is available from CL:AIRE, the leading independent research body into soil and groundwater contamination in the UK.