Land gas can arise from a variety of sources, both natural and man-made. Landfill sites are undoubtedly the commonest man-made sources of land gas. Landfill gas is a complex mixture of gases that changes over time as the landfill ‘matures’.
Perhaps the most common sources of land gas are naturally occurring sources in organic soils such as peat, coal, and fluvial or marine alluvium. These typically generate methane and carbon dioxide but other gases, such as hydrogen sulphide can also be present.
A site might be affected by land gas from sources that could be present on site or in the vicinity.
Land gases are hazardous to man and the environment due to their toxicity, asphyxiant properties or flammability. There have been a number of high profile cases where the presence of land gas has resulted in human deaths, and the destruction of property by explosion. For this reason, we believe land gas monitoring & assessment to be an important part of our overall environmental consultancy services.
Due to the hazards presented by land gas, there is a need to investigate sites that could be affected, to assess the risks and, if necessary, put in place remedial or protection measures to manage the risk.
Monitoring Land Gas
We provide a full site investigation and ground assessment service, from initial desk study through to intrusive ground investigation, installation of monitoring wells, gas monitoring and testing, and risk assessment.
Our site investigation teams are experienced in gas risk assessment for new developments and existing buildings, cross-boundary migration monitoring, and surface emission surveys of former landfill sites.