Dr Mariann Lloyd-Smith PhD (Law), Senior Policy Advisor, IPEN – International POPs Elimination Network, and Senior Advisor, National Toxics Network Inc. This article first appeared in the summer 2014 edition of the RSGS's magazine, The Geographer.
Exploration and production of natural gas from unconventional sources such as coal seams and shale are rapidly expanding in Australia, with a predicted 40,000 coal seam gas (CSG) wells to be developed in Queensland alone. Community concerns over the contamination of groundwater, surface water and air are escalating, bringing together an unlikely alliance of farming communities and environmentalists united in their opposition to further development of unconventional gas fields. Recent New South Wales legislation introducing a 2km buffer zone around urban areas and certain agricultural infrastructure has seen some Australian CSG companies leave Australia to pursue opportunities in the UK, Ireland and Europe where such restrictions do not exist.
Opposition to CSG and shale gas has grown in Australia as more evidence of pollution and the environmental and social impacts on rural communities has come to light. The limited publicly-available data on chemical use and releases in the drilling and production stages has increased concerns around the potential for water pollution and the public costs of managing the wastes.
‘Fracking’ (hydraulic fracturing) involves injecting wells at high pressure with water, proppants, radioactive tracers and chemical additives, to fracture the formation and produce new cracks and pathways to help extract the gas. While industry claims that chemical additives are minimal, consisting of less than 2% of the fracking fluid, a risk assessment provided to the Queensland Government identified c18,500kg of chemical additive used per well, with up to 40% not recovered. These quantities, although extraordinary, were consistent with the 2011 European Parliament report which estimated 16,000kg of acutely toxic substances were used to frack tight gas in Lower Saxony, Germany. Wells may also be fracked a number of times.
The chemicals listed in the risk assessments included surfactants, lubricants, acids, scale and corrosion inhibitors, and biocides. Some chemical ingredients could not be identified in the Material Safety Data Sheet (MSDS) due to commercial confidentiality, but of those identified, many had acute or chronic toxicity warnings. The majority had only limited data on environmental fate and ecotoxicology.
Waste Water - CSG activities generate large quantities of ‘produced’ water, reported by Australian industry to be 0.1-0.8 megalitres per day. Produced water may be contaminated with heavy metals, naturally-occurring radioactive substances, fracking or drilling chemicals, high quantities of salt, BTEX (benzene, toluene, ethylbenzene, xylene), and naturally-formed halogenated chemicals. Currently, produced water in Australia is managed by ‘storage’ in large holding ponds, used for dust suppression on roads, ‘treated’ and released into waterways, or sold on for use in irrigation.
Water Contamination - In 2011, bromine was detected in treated and released CSG water at six times background levels. Methane, not detected in the upstream control sample, was detected at 68 micrograms per litre. In Australia, there has been little comprehensive testing of groundwater, despite the fact that industry has reported BTEX chemicals in five out of 14 monitoring wells in Queensland.
Proppants and Silicosis - The extensive use of proppants is also causing concern. Proppants consist of either sand/silica or manufactured ceramic polymer spheres based on alumino-silicates, which are injected as part of the fracturing fluid mixture and intended to hold open the fractures once the pressure is released. Breathing silica can cause silicosis, is a known cause of lung cancer, and is suspected of contributing to autoimmune diseases, chronic obstructive pulmonary disease, chronic kidney disease.
Methane and Climate - Impacts Unconventional gas is promoted as a ‘cleaner fossil fuel’ compared to coal, but ongoing concern over the climate impacts of the lifecycle of gas from shale and coal seams has resulted in Australian research on the industry’s fugitive emissions. Researchers have suggested that CSG activities change the geological structure and enhance diffuse soil gas exchange processes, helping gases to seep through the soil to be released to the atmosphere.
Air Pollutants - While there are few publicly- available reports of formal air monitoring data related to CSG activities in Australia, limited government and community sampling of ambient air around CSG activities has detected many VOCs. Residents report symptoms of severe headaches, nausea, vomiting, nose bleeds, eye and throat irritations, severe skin irritations and paraesthesia in children. A preliminary health investigation by the Queensland Health Department concluded there was “some evidence that might associate some of the residents’ symptoms to exposures to airborne contaminants arising from CSG activities”.
Conclusion - With no baseline data collected prior to the CSG and shale activities, it is impossible to clearly establish cause and effect relationships. However, there can be no doubt that both community and environmental health has deteriorated in certain regions since the unconventional gas industry was established. If a proper cost-benefit analysis had been done prior to granting approvals for these projects, regulators and governments may have concluded that this industry was simply not worth the risks to community and environmental health.
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