WDE conducts all Risk Assessments and Remedial Strategies in line with current UK guidance issued by DEFRA and the Environment Agency. In particular, the CLR-11 report provides a methodology and framework to be adopted during the assessment and management of contaminated land.
Risk Assessments include the following stages:
- Preliminary Risk Assessment (initial site conceptual model)
- Generic Risk Assessment (comparison with published guideline values)
- Detailed Quantitative Risk Assessment (generation of site specific risk based values)
Even when pollutant linkages are identified, judgements based on the context of the risk need to be made to determine whether the level of risk justifies undertaking remedial actions. Factors such as the site setting, current and proposed site use and the building design need to be included so that the model targets derived are specific to the site being assessed.
Remedial Strategies will build on the Risk Assessment to clarify what actions are required to make the site suitable for the intended land use. As such they comprise the following:
- Remedial Criteria (based on Risk Assessment)
- Remedial Options Appraisal
- Selection of Remedial Methods/Pathway Control Methods
- Verification Plan and Closure