A Remediation Strategy sets out the measures needed to address unacceptable risks identified during the Phase 2 Contaminated Land Risk Assessment. If the site investigation confirms source–pathway–receptor linkages that could present a risk to human health, controlled waters or property, suitable mitigation measures must be designed and documented.
Local planning authorities and environmental health officers require a Remediation Strategy before development can proceed. The document outlines the recommended remediation methods, how they will be implemented and the criteria that must be met for final regulatory approval.
Clean Cover Systems
For risks to human health in areas of soft landscaping, private gardens or public open space, a clean cover system is commonly used. This typically involves up to 600 mm of certified clean topsoil and subsoil, sometimes installed over a geotextile layer. The clean cover breaks the exposure pathway between contaminants in the underlying soil and future site users.
Ground Gas Protection
Ground gas mitigation measures are designed in line with British Standards. Depending on the risk classification, protection may include:
These measures must be validated as correctly installed by a competent and independent specialist.
IGE specialise in the design and verification of ground gas protection measures.
Controlled Waters Remediation
If risks to controlled waters are identified, several options may be considered:
More complex engineered systems are only required on a minority of sites, as many contaminants naturally break down before reaching sensitive receptors.
Once remedial measures have been installed, they must be independently verified before the site can be occupied. This is required by the Local Authority Environmental Health Officer and, where applicable, the NHBC.
A Validation Report confirms that:
This report is usually the final document required before full regulatory sign‑off and pre‑occupation approval.
