'Contaminated land' is used in general terms to describe land polluted by:
- heavy metals, eg arsenic, cadmium and lead
- oils and tars
- chemical substances and preparations, eg solvents
- radioactive substances
Contaminated land is defined legally as land where substances could cause:
- significant harm to people or protected species
- significant pollution of surface waters or groundwater
This definition refers to contamination caused by past uses of sites such as:
- former factories
Land is defined as radioactive when a person could be harmed by spending time on land where radioactivity is present.
Some types of contaminated land are classed as special sites. This includes land that:
- seriously affects drinking waters, surface waters (for example lakes and rivers) and important groundwater sources
- has been, or is being, used for certain industrial activities, such as oil refining or making explosives
- is being or has been regulated using a permit issued under the integrated pollution control or pollution prevention and control regimes
- has been used to get rid of waste acid tars
- is owned or occupied by the Ministry of Defence
- is contaminated by radioactivity
- is a nuclear site
The Environment Agency has technical guidance on special sites.
Once a local council has decided that an area is a special site, it is regulated by the Scottish Environment Protection Agency (SEPA).