Land pollution

Contaminated land is defined 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:

• Significant harm is being caused or there is a significant possibility of such harm being caused.
• Pollution of controlled waters is being, or is likely to be, caused'.

For any piece of land to be considered as contaminated, a pollutant linkage must exist.  This means there should be a source of contamination (such as oil or heavy metals within the soil), a receptor (such as a person, groundwater or protected ecosystem) and a pathway, which links the two together.  A pathway may be exposed soil, which allows people to come into contact with the contaminant or permeable geology, which allows contaminants to move (migrate) to underlying groundwater or a nearby ecosystem.  The relationship can be shown as the following diagram:

Contaminant                            +                    Pathway                      +       Receptor
(methane at a landfill site)                 (gas permeable rock strata)           (houses)

What are the issues?

In the past, industrial activities have allowed land to become contaminated in various ways over many years. This land includes industrial, mining and waste disposal sites. Landfilling of waste sometimes took place without adequate precautions against leaching or the escape of landfill gases.

Land in this condition, if not dealt with adequately, can pose a serious threat to health or the environment, including pollution of the water environment. Land contamination can cause economic and financial damage. Uncertainties about remediation requirements and liability for them can cause blight, deterring development of land and adding to pressures on greenfield sites, and affecting urban regeneration.

Role of environmental protection

Environmental Protection has three primary roles:

• To undertake the implementation of Part IIA of the Environmental Act 1990 within the city.
• To provide advice on contaminated land issues to the planning department in relation to planning applications.
• To provide advice relating to contaminated land issues to the City Council and the public.

History of the city and implications for contaminated land

Coventry has a long and varied industrial heritage. Many of these activities have resulted in land becoming contaminated, or left containing substances, which could become an issue in the future.

Coventry is thought to have originated as an Anglo Saxon settlement. In the 14th century walls were built around the City, which limited expansion, and Coventry became a dirty and densely built town surrounded by pastures and parkland, the majority of which could not be built on. With an ever-increasing industrial population and limited space much development was forced to take place in the lanes, yards and gardens, creating city slums.

In 1845 an Act was passed that released a substantial area of land for development. Hence, during the 19th century the city began its industrial expansion. This was particularly rapid in the north-east where the canal and railway attracted the building of factories. This is where the ribbon industry concentrated, while to the South and West watch making became the dominant industry. Much of the industrial development in the decade before World War I centred upon Radford and Foleshill with the construction of the Courtaulds and Daimler works.

Between the wars the pattern of Coventry's growth was heavily influenced by the location of important factories, which were built or enlarged on the outskirts. These were mostly connected with the motor trade and included the Humber works at Pinley and the Standard works at Whoberley, the Armstrong Siddeley Aircraft works (later belonging to General Electric Company) and the Dunlop works at Whitmore Park.

During the industrial rehabilitation of Coventry in the late 19th century, former weaving factories and workshops were taken over by cycle and light engineering firms. The central area of the city had become a jumble of cramped industrial premises, public buildings and housing.

The importance of Coventry as a centre of war production made it a target of German air raids, and 21 important factories were badly damaged along with much of the city centre. In 1957, a Statutory Development Plan was approved, and the location of industrial development was restricted. The area within the inner Ring Road was zoned for light industry. On the outskirts of the city most of the large factories continued to increase in size.

Coal mining has historically been a dominant industry in the Coventry area, with several working collieries. By 1941 Coventry colliery was the largest colliery in the region, producing an excess of 850,00 tonnes/year, however, production ceased in 1991 after 74 years of operation. Hawkesbury colliery ceased production in 1946 and Exhall ceased production in 1948.

The historical development of the city means that the type of industries that could potentially give rise to contaminated land have been sporadically distributed and continually changing.

Undeveloped and greenfield sites are now recognized as being a finite and extremely valuable resource. The benefits of this approach will include reduced pressures on greenfield sites and rural areas as well as the restoration of contaminated land to a more productive use. The Government has set a national target of achieving sixty percent new dwellings on previously developed land by 2008.