|
|
|
IETG
|
|
|
BROWNFIELD DEVELOPMENT
 Sustainability and care for the environment used to be for 'tree huggers' and environmentalists, but more urban developers are finding that the use of a sustainable approach to Brownfield site development can reap rewards.
Research has shown that there are 350,000 hectares of contaminated land in the UK. This land is the product of the changing nature of our industry and economy where the decline in heavy industry has left large areas of land vacant and derelict. There is now a growing acceptance of the need to address sustainability and of the need to recycle resources generally. Recycling land is one aspect of this concept and one that is growing in favour as examples are produced that show that the process is achievable and realistic in terms of technology and costs.
IETG(Integrated Environmental Technology Group) has developed an approach to sustainable urban development that is gaining wide spread acceptance.
Contaminatedland investigation typically consists of discrete stages. There is the desk study, using historical information to establish past uses of the site and the surroundings to give a general feel for the likelihood of contaminative risk. In addition information from statutory bodies and local authorities about the site and surrounding areas is reviewed, including data regarding the location of landfill sites, water quality classifications and site investigation reports. Although not essential, IETG has found that this data can form the basis of a map based GIS system to make the data searchable, relevant, useful and instantly available.
Many water companies now require that all new services must be laid in uncontaminated ground. Developers are required to demonstrate that service runs are uncontaminated by providing chemical data on ground conditions, as well as the presence of groundwater and soil gases. At IETG, the geotechnical sampling is followed by chemical tests, borehole monitoring and gas analyses, usually by the same team and the results added to the site archive by direct data entry on site.
The site will also be investigated for soil gases as harmful concentrations of gas, such as methane and carbon dioxide, can build up in the soil and particularly in voids beneath and within buildings. The air emissions team within IETG is UKAS accredited for air borne particle analysis and has provided boundary-monitoring schemes for many sites to EnvironmentAgency requirements. The data is added to the GIS map as an air emission overlay to record background pre-existing conditions.
The risk to a proposed development from contaminated land is usually assessed using Source-Pathway-Receptor analysis. This technique establishes the presence of a chain of events required to present a risk, indicating both the receptor and the source, bearing in mind that the identified risk need not necessarily be within the boundaries of the site itself.
All these considerations and more must be borne in mind when drawing up a remediation strategy. The nature of this strategy can vary enormously, depending on the size and location of the site, the extent and nature of contamination and the design and use of the proposed development, among other factors. One common theme however is that, by using IETG's services, it is possible and practical to re-mediate the vast majority of Brownfield sites economically and effectively.
|
|
|
