Case Study: Bawtry Gas Works
There are a large number of sites formerly used for the production of town gas. One such site is in Bawtry, Yorkshire. It began operating in the First World War (1915) and belonged to the Bawtry and District Gas Company from 1912 to 1931. It was transferred to South Yorkshire and Derbyshire Gas Company (in 1931). After the Second World War it was transferred again as part of a nationalisation programme under the Gas Act 1948. It was run by the East Midlands Gas Board but production of gas at the site ceased around 1952. After that it was used as a depot. As with many former gas works in the 1960s it became redundant with the shift to natural gas and was sold, in 1965, to a firm of house builders.
Because the production of town gas involves burning coal in an oxygen starved environment, this process produced tars which were heavily contaminated, especially with heavy metals. A small housing estate was soon built on the site by the developer but the pits containing tars and certain other underground storage tanks were never removed. It was only in 2001 when a resident of the housing estate was digging in the garden that a tar pit was discovered. This led to the determination that the land on which 11 houses (all with gardens) stood constituted contaminated land.
Where land contamination causes or may cause water pollution, the site may be labelled a 'special site' so that enforcement of the Act passes from the local authority to the Environment Agency. This was the case in Bawtry. Although tar pits in gardens presented an obvious threat of significant harm to human health, since coal tar is a carcinogen (can cause cancer) in this instance the tar pits were also leaking into underground water. A major aquifer (water source) underneath the site was used for water abstraction, and the contamination from the tar pits was causing pollution of this groundwater.
The determination of contaminated land can lead to the service of a remediation notice requiring appropriate persons to clean up the site. Usually the appropriate persons would be those companies that caused the pollution to be there such as the gas companies. But the East Midlands Gas Board was wound up when the gas industry was privatised. British Gas took over from East Midlands Gas Board in 1986 when Margaret Thatcher privatised the gas industry. But British Gas and later companies such as Transco had never occupied the site. The Court found they could not be held responsible for a site sold some years before.
It is also possible to demand that someone who fails to clear up a site when able to do so, where they knew of the pollution on the site, should clean it up. This could mean that the house builders who failed to remove the tars from the site might have been held responsible. But the company that built the houses had been wound up some years before. The Court found that no-one could be made to clean up the estate.
Nonetheless because people were living in the houses and because of the water pollution, clean up was a matter of urgency. The Environment Agency could have tried to make the house owners pay for the work that was done, but the cost for the clean-up work for the eleven properties was £695,782, averaging £63,253 per property. The Agency decided this would cause hardship to the residents and that it would be unfair to make them pay.
The clean-up was funded at public expense. There was a fuller site survey to locate any remaining underground structures. All structures were removed together with any contaminated materials. This included all contaminated soils to a depth of at least 0.6m, and a separator was installed at 0.6m below ground to prevent contact by residents with residual contamination at any lower depth. The soil dug out was replaced with new fill of a type suitable for domestic gardens and there was full restoration of levels of the land, drainage, boundaries and garden/domestic infrastructure.
All ended well for these householders, but the case study shows that it makes sense to take care if you are buying a house on former industrial land. About two thirds of all new houses are built on land that has already been developed in the past. Your solicitor will check for you but if you know something of the industrial history of the site, because, for example, you have lived nearby for some time, do mention this to your solicitor.