Most companies in heavy industry and manufacturing have to deal with historical contamination caused by operations, which in the past were legal and acceptable, but are now no longer necessarily considered to be good practice.
The main causes of contamination, on industrial sites, have been leaks and spills at factories and disposal of wastes in uncontained landfill sites. Possible risks vary widely depending on the type of non product output involved, its concentration, local geology and hydrogeology, desired use of the land and whether there is the potential for impact. Much industrial contamination of soil does not pose an immediate hazard, as long as it is left undisturbed. Contamination that is a concern in terms of human health or the environment, usually has to be dealt with immediately to comply with the law.
Nevertheless ICI requires all its businesses to evaluate the potential for land contamination in and around their sites.
ICI has a five-stage risk management approach to the issue:
1. Historical review
Past and present activities on the site as well as its environmental setting are reviewed. This information is analysed to see if further checks are necessary. Many of the investigations stop here because there is no problem.
2. Intrusive investigations
This may involve drilling boreholes and taking samples for analysis.
3. Risk Assessment
The risks of any contamination are assessed using the information from the historical review and the intrusive investigations We look for situations where a source of contamination may cause an unacceptable level of risk to a defined receptor, via a possible pathway. Many of the sites that reach this stage are shown to be of low risk.
4. Assess remediation or control measures
A decision is made on the type of remediation or other action needed, based on the level of risk. This may be to remediate the source, block or remove the pathway, or otherwise protect the receptor.
5. Action
The remediation or control measures are carried out and the result is monitored.
ICI is proactive and thorough in its approach and works with regulatory bodies and local communities. An example of our approach to managing land legacy issues is Weston Quarries, Runcorn, England.
A number of years ago we started a voluntary investigation into the legacy of about 160 years of industrial activity on and around our previously owned Runcorn site in north-west England, with the aim of identifying any significant risk to people or the environment from this activity.
During the work we identified that a by-product from some of the processes – hexachlorobutadiene (HCBD) – had been disposed of in old quarries near Weston village, close to the Runcorn site.
An extensive technical investigation was started and confirmed that HCBD vapour had moved through rubble from the quarrying operations and entered some houses. A range of support policies to help local residents was introduced. The investigation was intensified, involving independent experts from around the world, and confirmed that the large majority of the village area was not at risk of exposure to HCBD. Unfortunately some properties were affected and this resulted in a total of 37 properties being demolished and the area being landscaped.
An examination by the responsible authorities of the patterns of illness and disease in the residents and local population has not revealed any association with the quarries.
We report on our land assessment activities through our Sustainability Challenge 2010 programme of Sustainability objectives.
