The intensive extraction methods needed to recover shale and tight gas have the potential to cause serious environmental and public and animal health impacts. Fracking and the heavy use of toxic chemicals pose significant hazards.
Major environmental impacts include water contamination, soil contamination, health impacts to living organisms exposed to chemicals and waste products, hydrological impacts from water consumption and extraction, land clearing and habitat fragmentation, air emissions and induced seismic events.
Risk assessments have found that for the majority of these potential impacts the risks are high, particularly when their cumulative effects are taken into account.
Water contamination from gas well drilling is inevitable
In the US, where unconventional gas development has the longest history, there have been many reports of environmental problems. Drinking water and surface water contaminations from methane have been well documented. Pennsylvania's Secretary of State says that "Water contamination from gas well drilling is inevitable". For reference, Australia's national drinking water standards are published by the National Health and Medical Research Council.
Major environmental problems from unconventional gas projects have been widely reported in Australia. There have been numerous accounts of environmentally damaging leaks and spills of chemicals and wastewater resulting in vegetation dieback and animal deaths. One group keeping a public record of fracking related incidents is the Hunter Valley Protection Alliance.
According to SBS, there were 23 spills, three breaches during flooding, and four uncontrolled spills of CSG mining waste water in the first six months of 2011 alone.
Methane isn't toxic when inhaled, but by reducing the concentration of oxygen in the air it can result in suffocation in confined spaces (such as a room in a house). Drinking water that contains methane is not thought to be harmful, but there aren't many studies on the long-term health impacts of drinking water with high levels of methane.
When methane enters a domestic water supply and spurts from a tap the concentration is high enough to be combustible. If the gas has a concentration above 28 milligrams per litre, it needs to be vented, and when triggered it can explode. Methane can form an explosive mixture in air at levels as low as 5 percent. It is flammable over a range of concentrations (4.4–17%) in air at standard pressure.
Fire from Water
Gas fracking companies maintain that their activities are not the cause of methane gas bubbling up in rivers or for homeowners being able to light their tap water on fire. Instead, they insist both phenomena are natural occurrences.
Supporters of fracking point to the Gasland documentaries, which featured homeowners setting their kitchen tap water alight, and claim these scenes were a set up. Several blogs and websites are devoted to forensically deconstructing the Gasland films and characterising Josh Fox, the film-maker, as a fraud.
the evidence linking the flaming tap water to gas drilling...is overwhelming
Special effects mean that the specific scenes in the documentaries could have been staged to produce a 'wow' piece of footage. However, what is beyond doubt is that a technique known as isotope identification can be used to trace the origin of methane when it has migrated into drinking water or other water sources. The technique identifies the gas fingerprint of methane. Investigators in Pennsylvania used just this technique to locate the source of the gas that was causing tap water to explode and determined that the evidence linking the flaming tap water to gas drilling...is overwhelming.
Methane Bubbling Rivers
Fracking companies deny responsibility for methane gas bubbling up in rivers such as the Condamine in Queensland and the Nepean in NSW, and maintain that it's a natural occurrence which has nothing to do with their drilling activities. Long-term residents insist the phenomenon is new.
Without specific surveys before a project starts, it's extremely difficult to prove culpability when methane starts bubbling up in rivers and turns up in domestic water supplies. The lack of data means that the industry can't prove that it's not at fault and the community cannot prove that it is.
Unconventional gas companies could settle these 'is so/is not' matters once and for all by determining the extent of methane emissions in rivers and domestic water supplies before they start drilling. Given that the issues with the Nepean and Condamine rivers are far from isolated cases, why don't companies research escaping methane before their special seismic truck puts down its first vibration pad?
Alternatively, gas companies could undertake testing after methane migration becomes apparent. Isotope identification and gas fingerprinting is one method that could resolve claim and counter claim between residents and drillers.
Several doctors in Queensland suspect that patients living near gasfields are showing symptoms of gas exposure. They say the spate of ongoing symptoms, including rashes, headaches and nose bleeds experienced by families living near operational gas wells, are consistent with gas exposure. The doctors have reported their concerns to the Australian Medical Association.
Families living in the rural residential estates on what are now the Tara gasfields near Chinchilla have informed successive governments of health problems they attribute to the fracking that's been occurring near their homes since 2008. Their reports of sickness and ill health have been trivialised and ignored by government agencies. Not atypically, Tara is an area where the Queensland Government:
- undertook no baseline air or water monitoring or baseline health studies prior to permitting gasfields to be developed in close proximity to family homes
- did not undertake any ongoing health study or put in place any ongoing testing or health surveillance of residents to monitor chronic exposure levels
Communities living near hydrocarbon gas drilling operations have become de facto laboratories for the study of environmental toxicology.
Because the government's investigation of these complaints lacked appropriate clinical and environmental monitoring, the link between gasfield development and illness remains undetermined. According to the authors of the Impacts of Gas Drilling on Humans and Animal Health communities living near hydrocarbon gas drilling operations have become de facto laboratories for the study of environmental toxicology.
Air quality is adversely affected from well vents flaring methane into the atmosphere releasing dangerous VOCs and particulates into the air. VOCs are released from the huge condensate tanks and compressor stations, and when waste frack fluids that are stored in open lined pits evaporate and 'off-gas' into the air.
Air concentrations of potentially dangerous compounds and chemical mixtures are frequently present near oil and gas production sites. This is the conclusion of a recent US report on air pollution around unconventional gasfields.
a missing link between this industry and reported illnesses that we currently lack in Australia due to inadequate routine air monitoring.
The study showed that fracking releases high levels of potentially dangerous airborne pollutants into the air, with clear public health implications. Ass Prof Haswell-Elkins from the Faculty of Medicine at UNSW says the report provides "a missing link between this industry and reported illnesses that we currently lack in Australia due to inadequate routine air monitoring."
The issues confronting mainlanders living amongst Australia's gasfields echoes the situation in the US that's been unfolding over many years. In 2011, Wyoming's air quality near fracking sites was found to be worse than Los Angeles. Wyoming, the 10th largest US state - but the least populous, and the 2nd least densely populated - recorded ozone levels at 124 parts per billion, compared to the worst air day of the year for Los Angeles, at 114 parts per billion.
The US Environmental Protection Agency's maximum healthy limit is 75 parts per billion. An earlier report from 2007 prepared for the Western Governors Association inventoried the present nitrogen oxide and sulfur dioxide emissions (smog) from oil and gas drilling in the west, and projected that Montana was likely to experience a future of a 310% increase in nitrogen oxide pollution.
Besides methane, numerous other air contaminants are released during the various operational stages, including construction and operation, transport of materials and equipment, and waste disposal. Some of the pollutants released by drilling include: benzene, toluene, xylene and ethyl benzene (BTEX), particulate matter and dust, ground level ozone, or smog, nitrogen oxides, carbon monoxide, formaldehyde and metals contained in diesel fuel combustion—with exposure to these pollutants known to cause short-term illness, cancer, organ damage, nervous system disorders and birth defects or even death.
Because chemical exposure is insidious and cumulative, it can take years before the true magnitude of the effects on people's health as a result of air pollution from unconventional gas development is really apparent.
Large scale sand mining to feed the fracking industry is adding to air pollution and bringing concerns about the potential health risks from massive quantities of airborne crystalline silica. Crystalline silica, in the form of sand, can cause silicosis, an incurable but preventable lung disease, when inhaled.
The National Institute for Occupational Safety (NIOSH) collected air samples from 11 fracking sites across the US. Data from all 11 sites exceeded the health criteria for exposure to respirable crystalline silica. At several of the sites silica concentrations exceeded the NIOSH exposure limit by a factor of 10, which means that even if workers were wearing proper respiratory equipment, they would not be adequately protected.
Light pollution from gasfields and well vent flaring is so intense it can be seen in satellite photos burning almost as brightly as major cities such as Minneapolis and Chicago. Gas well vent flaring is an integral part of fracking operations. It occurs when unwanted or excess methane gas is flared or burnt off into the atmosphere from the well head.
In previously serene rural areas light pollution interferes with residents' normal routines, disrupts livestock, wildlife – particularly nocturnal species - and affects carefully calibrated instruments in the area, such as astronomy and radio telescopes.
UTAS operates two important research sites in Tasmania, the Greenhill Observatory at Bisdee Tier in the Southern Midlands and the Mt Pleasant Radio Telescope Observatory near Hobart. The Greenhill Observatory sits squarely within the boundaries of the lease granted to PetraGas to explore for unconventional gas.
Light pollution from flaring methane and other airborne pollutants would threaten the viability of the Bisdee Tier observatory, which was only commissioned in 2013. This observatory is the largest optical astronomy telescope in Australia outside of Siding Spring, which is itself threatened by light pollution from CSG fracking in NSW.
Light, dust and other emissions also have the potential to affect the Mt Pleasant telescope. This radio telescope is part of the Australian VLBI (very long baseline interferometry) network, which is linked to the global VLBI network, undertaking global positioning work.
Noise pollution from fracking operations isn't usually considered to be much more than a minor, occasional irritant for people living near unconventional gas developments. However, noise pollution seriously impacts residents' amenity and disrupts ordinary farming and household routines. The constant rumble of hundreds of heavy vehicle and machinery movements, compressor stations running and gas well vents flaring, which has been likened to jet engines roaring 24/7 for weeks at a time, becomes a fact of everyday life for families who live in the vicinity of a gasfield.
Noise pollution is the sum of ambient sound that people perceive as unwanted. It includes noise from traffic, construction works, industrial operations and recreational activities. Noise becomes unwanted when it diminishes your quality of life by interfering with normal activities like sleeping, watching TV or holding a conversation.
Acute and chronic exposure to high levels of noise is associated with serious health risks, including hearing loss, sleep disturbance, stress, reduced school and work performance, headaches, high blood pressure, and other cardiovascular problems. Night time noise in particular has been found to increase these risks.
Unconventional gas developments are industrial processes that generate prolonged periods of noise pollution for workers and nearby communities. Well pad preparation, drilling, and 'well stimulation' (fracking) generate significant noise levels for neighbouring residences, schools, and work places. The noise from trucks, generators, drilling operations, and pumps can occur intermittently for days at a time and over several years as wells are fracked many times.
The practice of drilling multiple wells per well pad and infill drilling which increases well density can further increase the duration, frequency, and intensity of noise pollution. With the expansion of unconventional gas developments into more populated areas, a growing number of people are being potentially exposed to harmful noise pollution.