Working for Developers, Planning Professionals
& their Clients

Environmental Reporting Services

WPA provides a range of data reports with interpretation for use by solicitors, conveyancing firms, estate agents, building societies, banks and private individuals. They also form the basis, together with other searches and site reconnaissance action for informing desktop studies relating to Phase 1 site investigation described in the UK Government guidance document CLR11, Model Procedures for the Management of Land Contamination.

Risk Assessment and Site Investigation

Risk Assessment

Risk Assessment follows a tiered approach aimed at determining a point at which a clear decision can be made as to land use options using a protocol that considers contaminant linkages (source-pathway-receptor scenarios) in a site specific conceptual model.

WPA provides risk assessment in the areas of human health, risks to controlled waters and risks from ground-gases such as methane, carbon dioxide, hydrogen sulphide, and volatile organic compounds. Generic assessment criteria have been sourced to match UK technical guidance and site specific assessment criteria are generated using approved computer modelling techniques.

An invasive site investigation is part of the phased approach to considering land contamination described in the UK Government guidance document CLR11, Model Procedures for the Management of Land Contamination. It is informed by the phase one desktop investigation and involves the sampling of soils, water and ground-gas in a targeted manner taking account of the Geology, Hydrogeology, Hydrology, Topography, ground cover, land-uses and pollution events the site has experienced over recorded time.

WPA provides a complete service that includes the use of Geo-physics where appropriate, trial pitting and borehole installation with window sampling, groundwater sampling and monitoring for bulk gases and/or trace gases as necessary. Geotechnical investigation can also be provided by WPA to inform decisions concerning land stability and foundation design.


Risk assessment may identify potential and/or actual risks as requiring some form of mitigation to either manage or break the contaminant linkages of concern. A remediation scheme, or strategic approach to such mitigation, can be designed by WPA who have extensive in-house expertise. The challenge is to manage the issues without unnecessary recourse to digging out the contamination and transferring the problem to a landfill site.

WPA works with several innovative technologies deployed by a panel of approved contractors. We also provide a verification service to assist in the finalising of documentary material as evidence that contamination on a site has been appropriately dealt with - so that the site can be considered suitable for a particular use.