Site investigation
Approved document C, Site preparation and resistance to contaminants and moisture, suggests that the extent and level of site investigations needs to be tailored to the type of development and the previous use of land.
The approved document suggests that site investigations should consist of four well-defined stages:
- Planning stage: Setting clear objectives for the site investigation, including scope and requirements, which enable it to be planned and carried out efficiently and provide the required information.
- Desk study: Reviewing historical, geological and environmental information about the site.
- Site reconnaissance (a walkover survey): Identifying actual and potential hazards and the design of the main investigation.
- Main investigation and reporting: Including intrusive and non-intrusive sampling and testing to provide soil parameters for design and construction.
Site investigations should include:
- Susceptibility to groundwater levels and flow.
- Underlying geology, and ground and hydro-geological properties.
- Identification of physical hazards.
- Identification of methane and other gases.
- Determining an appropriate design.
- Providing soil parameters for design and construction.
Where a site may be affected by contaminants, a combined geotechnical and geo-environmental investigation should be considered and remediation maybe necessary.
It may also be necessary to notify findings to regulatory authorities, for example:
- Where contaminants are found that had not been previously known about.
- In planning applications.
- In relation to waste management and the protection of water quality and resources.
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