Brownfield regeneration can and should play an important part in climate change adaption and resilience. Regeneration should include preparation for, and response to, the challenge of climate change, and climate-related risks must be considered. Risk assessment is a fundamentally important component of a multi-disciplinary approach to successful brownfield regeneration and therefore the adoption and integration of climate change considerations in brownfield risk assessment is critical. We need to adjust our approach to brownfield risk assessment to account for actual or anticipated climate change and its effects on contaminant sources, pathways and receptors. This is why SoBRA is tackling the practical application of climate change in risk assessment head on at its 2022 Summer Conference and Workshop.

The re-use of brownfield land provides two key benefits in relation to climate change:

• It can help preserve our natural resources by reducing development on greenfield land.  This lack of greenfield development can then permit natural climate resilient activities, like infiltration, flood attenuation, and carbon sequestration, to occur on that undeveloped land that can help limit future climate impact.
• It can reduce the environmental impact of development. It can reduce the requirement for new transport infrastructure, improve the use of land in existing areas of development, can permit the re-use of existing buildings, and provides opportunities for centralised heat / power distribution.

Risk assessment is embedded in our regulatory approach to brownfield remediation and redevelopment in relation to soil and water contamination and potential risks to human health and the environment. The UK Government’s wider approach to the management of the environment, and climate change, should be no exception, with risk assessment fundamental to ongoing adaptation to climate change.

The key pillars of risk assessment – robust evidence, identification of hazards, consequences and their probabilities, and dealing with uncertainties and limitations – should also apply to our approach to climate change during brownfield regeneration. We should not be leaving the challenges of climate change solely to future generations; uncertainty over future impacts means a precautionary principle should be adopted in our risk assessments and approach to remediation of contaminated land. We should not be designing remediation schemes and brownfield redevelopment schemes that will not endure future climate change events. Key requirements of remediation schemes are effectiveness and durability – will they work throughout the timeframe required? A key requirement of risk assessment is the provision of robust evidence to inform risk management decisions on what risks might exist now and in the future.

All of this is rooted in a robust conceptual model of ground and contaminant conditions and how that might change with time. We cannot prevent climate change and adapting to future changes must be taken into consideration during our decision making.

We cannot adapt efficiently and effectively to climate change without robust risk assessment. One of the key challenges is the uncertainty in what climate change means in practice for a particular site – what might the impacts be and when might they be realised? We would argue that as an industry, we can evaluate, and manage, those uncertainties along with all the other uncertainties that we invariably must consider within conceptual models for brownfield sites. Existing approaches to assessing uncertainty can be used in many cases and expanding our sources of information and/or widening our collaboration with other disciplines such as flood risk will provide cross-industry knowledge transfer to enhance all our approaches.

Our industry is already developing ideas and approaches to how to tackle this additional consideration in brownfield risk assessment. Collaborative initiatives are already in play, and this is great to see. Climate change should be a consideration (even if it is ruled out early) in every investigation of a potentially contaminated site. The Environment Agency LCRM guidance does already recommend the incorporation of climate change considerations into land contamination risk assessment and the options appraisal process to ensure site works and any long-term remediation are sustainably robust.

The SoBRA sub-groups will be discussing the potential implications of climate change for their area of specialism at the 2022 Summer Conference and Workshop, alongside the practical application and incorporation of climate change into existing risk assessment methodologies. With SoBRA and other organisations initiatives due to be published later this year maybe as an industry we will have some consensus and direction on a way forward for brownfield risk assessment sooner than we might think.