Former landfills and contaminates sites, such as old industrial and petrochemical storage areas, pose a risk to current and future developments. The redevelopment of ‘brown field’ sites is becoming increasingly popular to minimise urban sprawl. Historically, sites used as landfills or similar, previously seen as unfavourable, are now considered as potential development areas for major infrastructure projects through to residential housing. Due to the nature of these sites it is not uncommon to find the area contaminated with waste and other hazardous materials that, if exposed or built on, could pose a risk to human health through exposure to associated ground gases. Ground gases generally originate from the decomposition of organic material and other contaminants such as fuels and oils. Gases released may include methane, carbon dioxide and hydrogen sulphur including other explosive and hazardous gases. The presence, nature and flow rate of ground gases in any ‘brown field’ site needs to be assessed to appropriate manage the risk during construction (construction phase) and enable the final design to accommodate and manage the risk long-term (operational phase). The monitoring and management of ground gases will form part of the project’s Detailed Site Investigation and Contaminated Sites requirements. For more information please refer to the Department of Environment Contaminated Sites Guidelines and CIRIA C665 guidelines for assessing risks posed by hazardous gases to buildings.
Environmental Site Services can manage the installation of ground gas wells and monitoring of ground gases, whether automated systems for continuous monitoring or attended onsite monitoring, to meet your ground gas monitoring program and contaminated sites requirements.