Coal seam gas extraction at Windibri Gas Field near Chinchilla. Image: Adam Creed.
BY CAMERON DRUMMOND
STUDIES from the CSIRO and the National Industrial Chemicals Notification and Assessment Scheme (NICNAS) have reported that chemicals used in the coal seam gas (CSG) industry poses little risk to the community or the environment.
The studies assessed the human health and environmental impacts of chemicals used in drilling and hydraulic fracturing for CSG extraction in Australia between 2010 and 2012. It found that residual chemicals remaining underground after hydraulic fracturing were unlikely to reach people or ecosystems in concentrations that would cause concern.
The collaborative Understanding the fate of coal seam gas chemicals report found that in the event of a small spill (typically several litres), soil contamination remained shallow – at depths of less than two metres.
For large spills, (a tank volume up to 15,000 litres), groundwater contamination may occur only if the soil groundwater interface was shallow (between 4 and 6 metres); if not, emergency response – consisting of containment, isolation and decontamination – was to occur within 10 days of the spill.
The NICNAS assessment found the most significant potential risk to public health and the environment was exposure to chemicals after a large-scale transport spill; a risk facing any industry that uses chemicals.
Australian Petroleum Production & Exploration Association (APPEA) chief executive Dr Malcolm Roberts said the studies were just the latest independent research which should reassure people that hydraulic fracturing is safe when properly regulated.
“The chemicals used for hydraulic fracturing in the CSG industry accounts for less than one hundredth of one per cent of chemicals transported by road in Australia,” Dr Roberts said.
“Extensive regulation of heavy vehicle movements and chemical storage already minimises the risks identified.
“Australia’s natural gas industry provided data to the NICNAS assessment and will consider its findings.
“However, it should be noted that some 80 per cent of the 40,000 chemicals approved for use across all Australian industries are yet to be assessed by NICNAS in the same way.”