Contaminated Land
Our team have a wealth of experience on Contaminated Land assessments across UK and Ireland.
Our senior consultants have experience in providing Contaminated Land assessment services for high profile development and infrastructure projects across the UK.
In the UK the adopted risk assessment approach to contaminated, or potentially contaminated, land are the Model Procedures for the management of land contamination known as CLR11. The guidance follows a conceptual model process whereby sources, pathways and receptors are looked at on a site-specific basis and in consideration to the surrounding site environment.
Risk assessments are required to determine potential risks to on and off-site environmental receptors which may be affected by development, and to assess the potential risks to human health due to occupancy and work over contaminated sites.
The model procedure and risk assessment process may range from a straightforward desktop study, or to a more complex quantitative assessment which may include site specific measurements, ground investigation information, and the monitoring of ground gases and groundwater beneath the site.
Following the CLR11 model procedures, the risk assessment process should always start with a Phase 1 Preliminary Risk Assessment (PRA). The PRA seeks to establish if there are any potentially complete pollutant linkages and any unacceptable risks.
An initial conceptual site model is produced to outline the possible relationships between sources-pathway-receptors. Should any complete pollutant linkages be identified and uncertainties be uncovered at the PRA stage which identify unacceptable risks further actions are required which, following CLR11 model procedure process involves a Generic Quantitative Risk Assessment (GQRA or Phase 2) which requires an intrusive investigation.
If a Phase 1 PRA identifies unacceptable human health and / or environmental risk, then regulators will require that the site is further assessed with site specific data.
This is achieved by way of an intrusive investigation, which typically includes the collection of soil and groundwater samples, though may also include vapour, ground gas and surface water.
The information obtained from these investigations is then assessed against generic assessment criteria (QGRA).
If the GQRA identifies unacceptable pollutant linkages further action will be required, through an options appraisal process. This may be in the form of a Remediation Strategy, which when implemented would break the complete pollutant linkage, for example by removal the source or eliminating the pathway, or elimination of the pathway by installation of an impermeable membrane.
A Remedial Validation Report would then be required to confirm the Remediation Strategy has been correctly incorporated into the final development.
Our senior environmental consultants have extensive experience in the design and supervision of ground investigations in line with current Codes of Practice such as BS10175 and Eurocode 7/BS5930.
We also have experience in designing appropriate ground gas and groundwater monitoring wells and monitoring regimes in line with current British Standards and CIRIA guidance.
We can complete Remedial Action Plans and Validation/Verification reports for submission and agreement with Local Authority, to enable contaminated land conditions to be discharged on residential sites; in addition to completing Land Contamination Statements to support Planning Applications.
