Land remediation
Completion of an appropriate site investigation will enable the formulation of a robust Conceptual Site Model, which considers plausible pollutant linkages. Where plausible pathways between actual contaminant sources and potential receptors are identified, remediation will be required, either treatment/removal of the source, or “breakage” of the pathway.
- Isolation beneath cover
- Ex-situ bioremediation
- Soil washing
- Solidification or stabilisation
- Recovery of coarse fraction
- Soil vapour extraction
- Excavation & disposal
In addition, Lithos also consider the need for ground improvement, and\or the earthworks necessary to create a platform on which development can commence. Choice of the most appropriate remediation option(s) is influenced by:
(a) The Conceptual Ground Model, including:
- Geology, hydrogeology, proximity to watercourses etc
- Volume and distribution of soil requiring remediation
- Nature (eg gravely or clayey) of soil requiring remediation
- Nature of the contaminants – the “mixture”, mobility, volatility, and resistance to degradation
(b) Classification of the soil for the purposes of disposal to landfill:
- Site’s size – area available for remediation activities
- Site’s location – consideration of odour, dust and noise associated with remediation activities
- Redevelopment proposals
- Estimated costs and timescale associated with the proposed remediation technique
- Degree of confidence/certainty in proposed remediation technique
- Views of the Local Authority
Remediation options for contaminated soils include:
- Isolation beneath cover
- Ex-situ bioremediation
- Soil washing
- Solidification or stabilisation
- Recovery of coarse fraction
- Soil vapour extraction
- Excavation & disposal
And for contaminated groundwaters include:
- Pump & treat
- Chemical oxidation
- Dual-Phase Vacuum Extraction (DVE)
- Bioremediation
- Attenuation monitoring
Once a specific development scheme has been decided, we can prepare a Remediation Strategy Report, for submission to the Local Planning Authority.
A Remediation Strategy outlines the remediation objectives necessary to protect environmental receptors, and render a site suitable for the proposed end use.
The Remediation Strategy will include site-specific clean-up criteria for contaminants of concern; the latter such criteria are usually derived by Quantitative Risk Assessment (QRA).
Lithos can supervise remediation works, and on satisfactory completion will prepare a Verification Report to stand as certification that works have been carried out in accordance with the approved Strategy. The Verification Report also provides recommendations with respect to:
- Foundation solution(s)
- Gas measures
- Placement of soil cover
- Handling and management of excavation arisings generated during construction
