Contaminated Land Site Investigations and Reports
South of the UK
What is a contaminated land site investigation? Why is it needed? What is involved?
These are all questions we have been asked many times. Based in Bristol, our dedicated team works with businesses and organisations in the South and across the UK, and we have the expertise to make the process as painless as possible and to advise you every step of the way.
A site investigation should be viewed as a process. It is essential that any site investigation or walkover survey for contaminated land is carried out in the correct manner and should follow the appropriate UK Guidelines, such as CLR11, in the case of contaminated land. Reports that do not follow this guidance will not be accepted by the regulators.
This guidance states that all contaminated land site investigations must be carried out in a phased manner.
This means that all site investigations carried out by our Bristol-based team should initially begin with a desktop study, also known as a phase 1 investigation. This will use existing data and possibly information gained from a visual site inspection (walkover survey) to allow a preliminary risk assessment to be carried out. If there is no risk from contamination in soils to site users or the wider environment, then no further action should be required.
Should a potential risk be identified during the desktop study of the site, then an intrusive investigation (or phase 2 investigation) will be required to establish the likelihood and extent of the risk.This can use a number of different methods from hand sampling through to drilling of boreholes with wells installed and must be based on the scope identified in the desktop study. It enables soils (and sometimes rocks) to be sampled and submitted for analysis and is what the layman thinks of as soil contamination testing. This is the stage that is generally thought of when people think of contaminated land site investigations and may be referred to as soil sampling, a soil survey, soil testing etc. This may also be combined with a geotechnical investigation of the land that allows data to be gathered on soil strength parameters to enable foundation design. The data gathered will be used to refine the conceptual model and risk assessment to establish whether a risk is present.
Should a risk be identified, then the next phase will be to carry out remediation. This may use a number of different techniques to mitigate the risks. We can guide you on this aspect too and find the most cost effective, appropriate way to deal with risks on your site.
So why is a site investigation of contaminated land necessary?
Soils across the UK have become contaminated from a number of different uses. Consequently, they may pose a risk to site users and to the wider environment if they are not dealt with appropriately. These sources are not just restricted to soils in industrial areas. Agricultural land use may have introduced contaminants into soils including old orchards where lead and arsenic were used as a pesticide. There may also be a risk from ground gas arising from landfill sites or filled ground – this may migrate over quite large distances and has been known to cause explosions destroying domestic properties if not dealt with adequately.
