Geophysical Investigations and Temporal Monitoring at Active and Disused Landfill Sites in South Wales

Most of the waste that is produced in England and Wales is sent to landfill, this amounts to about 100 million tones. When landfill sites become totally filled, often they are capped and some are redeveloped into parkland. The decomposition of organic material within the landfill leads to the production of a liquid leachate which has the potential of off-site migration. Non-invasive geophysical techniques, in particular Electrical Resistivity Tomography (ERT) can perform the internal investigation of active and disused landfill sites. Geophysical surveys have been carried out at three landfill sites in South Wales using a variety of surface geophysical techniques and buried electrode arrays to investigate the resolution capabilities of the technique. Repeated geophysical surveys also allow for the study of temporal changes within the landfill mass.