Potentially contaminated sites resulting from former development and historical land-uses are increasingly being considered for redevelopment across the UK. To allow for the successful redevelopment of these sites, the risks to human health and environmental liability need to be considered in terms of Source – Pathway – Receptor pollutant linkages.
When considering the redevelopment of potentially contaminated sites, the Source – Pathway – Receptor model is a commonly adopted approach for assessing the hazards and risks associated with the site. The model forms the basis for Part IIA contaminated land assessments. As outlined in CLR11, there are three essential elements to risk in relation to contaminated land and pollutant linkages:
- A contaminant source: a substance that is in, on, or under the land and has the potential to cause harm or to cause pollution of controlled waters;
- A receptor: in general terms, something that could be adversely affected by a contaminant, such as people, an ecological system, property, or a water body; and
- A pathway: a route or means by which a receptor can be exposed to, or affected by, a contaminant.
All three elements can exist independently however, where a connection is identified, the combination of the three results in a pollutant linkage. Developing a comprehensive Conceptual Site Model is a fundamental stage in understanding the potential for a pollutant linkage between any specified source, pathway and receptor, and subsequently what steps are required to reduce or mitigate risk.
Developing an understanding of the pollutant linkages forms the basis for targeted remediation strategies and efficient management of the risks. Understanding potential geo-hazards at a brownfield site at an early stage to avoid negative future financial impacts.
Examples of ESP experience: