Contaminated Land can occur for a number of reasons. These include past land uses, current land uses and incidents such as spills of chemicals or oil, etc. Unfortunately in the past, legal controls and standards over industrial and waste disposal were not sufficient to prevent land from being contaminated.
Contaminated land is defined within section 78A(2) of the Environmental Protection Act 1990 as:
'any land which appears to the local authority in whose area it is situated to be in such a condition, by reason of substances in, on or under the land, that:
a) significant harm is being caused or there is a significant possibility of such harm being caused
b) pollution of controlled waters is being, or is likely to be, caused'.
The definition includes pollutants that are naturally occurring, such as Arsenic which can be found in some areas of the UK at relatively high levels.
The associated Statutory Guidance expands on this definition and introduces the requirement for a pollutant linkage requiring a "contaminant, a receptor and a pathway" to exist.
For a site to be contaminated, a 'significant pollutant linkage' must always exist. The three components listed below must always be present to create a pollutant linkage:
Source - the contamination in, on or under the land
Pathway - route by which contamination reaches the receptor
Receptor - broadly defined as living organisms, ecological systems or property.
If there is a break in this pollutant linkage (i.e. there is a source and a receptor, but no pathway) the site cannot be defined as 'contaminated land'.
Types of current or historic contaminative uses
Generation, storage and distribution of power including gas works, electricity transformers and sub-stations.
Chemical industries including timber treatment works, engineering works, road vehicle fuelling, service and repair, sewage works.
Military activities including engineering works, vehicle depots, aircraft manufacturing, armament activities, radioactive materials use and storage.
Current and disused railways, sidings and goods yards.
Agricultural uses including chemical storage (pesticides / fertilisers), farm machinery storage, maintenance and repair, fuel storage, unlicensed waste disposal including burning and/or burial.