What does science say about fracking?

The federal government recently awarded $50 million in grants to private energy companies to fund the exploratory drilling of the Beetaloo Basin, as part of its heavily criticised “gas-led recovery”.

The 28,000 square kilometre Beetaloo region begins about 500 kilometres southeast of Darwin in the NT. The region, which includes Aboriginal lands and pastoral leases, is estimated to contain significant fossil fuel resources, including shale gas and shale oil.

But traditional owners have not given permission for fracking on their land and staunchly oppose it. Community members and pastoralists also continue to raise concerns about the health and environmental effects, and researchers question the decision to pursue new fossil fuel resources in the face of the climate emergency.

So what exactly is fracking, and what does science tell us about it?

Fracking: the basics

Hydraulic fracturing, also known as fracking, is an unconventional type of gas extraction. The process drills down much deeper than conventional methods, searching for fossil fuels such as oil and gas embedded in rocks.

There are many variations in the process depending on the technology or the geology, but the general approach is as follows.

First a well is drilled down to a gas- or oil-rich layer deep underground – often more than 3km below the surface. This process of drilling can take weeks, and the well is then usually lined with a steel casing to prevent contamination of groundwater.

Once it reaches the desired layer, the well is often then drilled horizontally for over a kilometre.

Then a cocktail of water, sand and chemicals is pumped into the well, creating extremely high pressures that cause the deep rock (shale) to fracture. The sand in the mixture holds the fissures open, so that gas or oil can escape from the rock – helped along by the chemical mix – and flow up the well to the surface to be collected.

The water and chemicals flow back out of the well, too, and are disposed of or treated.

Which other countries frack?

This technique was used as early as 1949 in Kansas, US, but it’s only really boomed in recent decades. In the mid-2000s, combining fracking with other methods like horizontal drilling made the process more profitable, and since then tens of thousands of wells have been drilled across the US. In the year 2000, fracking wells accounted for 7% of the nation’s gas supply; by 2015 they produced 67%.

However, not everyone is on board the fracking train. Other countries have banned the practice, including France, Germany, Ireland and the UK.

In Australia, the laws differ from state to state; for example, while Victoria has banned fracking, NT lifted their moratorium in 2018 after a 15-month-long scientific enquiry, which is why the Beetaloo Basin is now up for grabs.

So why is fracking so controversial?

Science says it’s all about the risks

Climate Council Senior Researcher Tim Baxter says that the consumption of natural gas not only contributes to climate change, but the process of fracking also poses “additional direct risks to the communities relying on the land and waters nearby”.

There has been a consistently high level of resistance to fracking from the public and from researchers, for reasons spanning health, environmental and social impacts, and the research is beginning to back up their concerns.

Use and contamination of water

Fracking requires millions of litres of water to form the fluid that is pumped underground. The number varies widely, depending on factors including the geology, the operator and the orientation of the well, but any excessive water use poses an issue in arid and remote regions.

The fracking fluid also contains a small percentage of chemicals, to reduce friction in the well, prevent the growth of bacteria, reduce mineral blockages, and prevent corrosion. Some of these added substances are every day (like salt and citric acid) and others are toxic (like benzene). While some fracking companies list the chemicals and additives used on their websites, and in WA it’s mandatory to do so, this doesn’t appear to be the case for other states.

To reach the depth necessary to extract gas or oil, wells often traverse underground aquifers; if the wells aren’t properly cased, fracking fluids containing a diverse mix of chemical ingredients can escape and contaminate groundwater.

The wastewater – the fluid that returns to the surface after fracking – also flows back up to the surface, typically still containing some of these chemicals and sometimes leaching materials from rock along the way. It is then either pumped back underground, stored in tanks or ponds, or sent off for treatment.

A study published last year found that this returning wastewater can contain salts, radioactive substances, carcinogens, solvents and petroleum distillates that can directly contaminate drinking water sources.

“Current methods for chemical characterisation of [wastewater] can give an estimate of the total amount of contamination but do not give information about what type of contamination is present,” says study author Emanuela Gionfriddo, from the University of Toledo.

“It could be that a molecule can be still very toxic even if present at very low concentration, or it has the potential to accumulate in the body over time, so the point is to know exactly what is in produced water, not only how much.”

Last month, research in Science also found that fracking can influence the quality of surface water, showing an increase in salt concentrations near wells, with potential health impacts.

But there are many unknowns, as changes to groundwater can take place over decades or even centuries. The big-picture of water contamination is still unclear.

A risk to health

Fracking has been linked to a range of negative health complications, including an increased risk of birth defects, certain cancers, asthma and other respiratory problems (potentially from decreased air quality), skin and eye irritation, damage to the nervous system and endocrine disruption.

Studies have also linked fracking with a higher risk for heart attacks, potentially due to air pollutants; higher concentrations of trace metals have been found in pregnant women who live near fracking wells in Canada; and the type of sand used in fracking fluid has been found to be an occupational hazard for workers.

Much of this research comes from North America, but there is a growing body of evidence from Australia, too.

For example, Baxter, who was an author on a recent report about fracking and health in Australia, notes that research in Queensland’s Darling Downs region has found that “people living near coal seam gas developments were more likely to be hospitalised for tumours, as well as blood and immune diseases. There were also significant increases in hospitalisations for respiratory diseases among children.”

Baxter says that there was very little research into human health impacts before the industry was approved in the Darling Downs region, and very little since.

“It doesn’t help that in Australia, the primary vehicle for researching the impact of the gas industry, including its health impacts, is a body that is funded and overseen by the gas industry itself,” he says.

Assessing the health impact of fracking is difficult, Baxter says, because “medically-relevant exposure to known environmental contaminants…from nearby gas infrastructure could be occurring over years or decades”.

In the US, where widespread fracking began in the mid-2000s, the scientific literature around the consequences of fracking is only now solidifying, so it may take Australian research years to catch up.

Fracking is also linked to documented social impacts, which are currently of concern for the traditional owners of the Beetaloo region.

In a recent Conversation article, Australian researchers highlighted studies into the negative mental health impacts in US communities near unconventional oil and gas production, as well as “the largely ignored links with sexual and physical violence experienced by Indigenous women and children in North America”.

The researchers wrote that these findings were “ignored in the NT fracking inquiry report and the subsequent Strategic Regional Environmental and Baseline Assessment (SREBA) framework”.

Fracturing subterranean rock causes earthquakes

Fracking can also cause earthquakes tens of kilometres away from wells.

By design, the extraction process produces small and usually unnoticeable earthquakes, because it involves breaking rock. However, injecting fluid can cause pre-existing geological faults (cracks in the Earth) to move or slip, like a skier triggering an avalanche.

Earthquakes can affect near the fracking site, but some have been reported up to 50 kilometres away. In regions – like Oklahoma in the US – where fracking wells are near high population densities, this puts millions of properties at risk of damage. Some localities consider the risk too high; in the Netherlands, the largest onshore natural gas field in Europe will be shut down by 2022 after continual severe damage to homes.

(Note that other technologies – including sources of clean energy like dry rock geothermal power stations – can also cause earthquakes through similar mechanisms.)

Methane emissions

Natural gas is largely composed of methane, which is an extremely potent greenhouse gas. Research has shown that it heats the planet 86 times more intensely than carbon dioxide over a 20-year period, and 28 times higher over 100 years. This short-term impact will have a huge influence on global temperature rise in the critical coming decades.

The expansion of the natural gas industry has caused an increase in methane emissions – in fact, a 2019 study found that the industry is responsible for two-thirds of the rise in global methane emissions between 2008 and 2014.

“This recent increase in methane is massive,” says Cornell University’s Robert Howarth, lead author of the study. “It’s globally significant. It’s contributed to some of the increase in global warming we’ve seen and shale gas is a major player.”

Shale gas produced by fracking accounted for more than half of this increase, partly due to gas being deliberately vented or flared as a necessary part of the safety process. But a proportion of gas is also accidentally released.

In 2016, a leak in Aliso Canyon storage well in California released as much pollution as 600,000 cars would over a year; nearby residents experienced nausea and headaches, among other health problems.

We need to wean ourselves off fossil fuels

Arguably the greatest risk of fracking is that it continues our dependence on fossil fuels, which scientists urgently warn we must stop using in order to limit global temperature rise and therefore the catastrophic effects of climate change.

“The industry should be wrapping up as quickly as possible and actually moving to the options that we already have,” says Tim Forcey, an independent energy advisor.

“There is no ‘gas-led recovery’ – it’s only a gas-industry-funded recovery of incumbent governments trying to get elected.”

Trained as a chemical engineer, Forcey spent 35 years in the oil and gas industry and has since worked with the Australian Energy Market Operator and the University of Melbourne. In 2018 he was involved in testifying as part of the NT fracking inquiry report.

He says that the idea of gas as a ‘transition fuel’ to wean ourselves off coal was something “the gas industry came up with 20 years ago, with the idea that gas might be cleaner than coal for making electricity. But these days, the information about how much of methane is being released into our atmosphere makes gas even dirtier than coal.”

Environmental engineer Gavin Mudd, from the RMIT School of Civil and Infrastructure Engineering, has previously estimated that burning black coal leads to one tonne of carbon emissions for every megawatt hour of electricity generated, while gas releases 0.7 tonnes of carbon emissions, and for renewables less than 0.1 tonnes.

Forcey points out that the industry’s pivot towards fracking may be because all the ‘easy’ oil and gas deposits have been exploited: “So you go to some quite exotic and invasive means including the fracking to try to scrape the bottom of that barrel – which we don’t need to do anymore because we’ve got better options.”

Choosing to frack, Forcey says, is kind of like “the drug addict, if they collapse all the other veins, then they start shooting between the fingers and toes”.

But there are far better, economically viable alternatives to natural gas from renewables.

“Australia is the sunniest continent on the planet and the windiest-inhabited continent,” says Baxter. “Our natural advantage in a zero-emissions future is simply mind-blowing.”

Forcey says that “any gas that’s being used in homes is basically an economic loss these days… Heating your home with your reverse cycle air conditioner, heating your water with a heat pump, cooking with an induction cooktop – all those things are better these days than using gas”.

Forcey also suspects that the push to frack the NT is less about gas than finding new avenues for oil production: “What the frackers are looking for more is oil rather than gas – oil you can make money from right away,” he says, as well as being easier to deal with.

But neither oil nor gas makes sense for Australia’s future, he says.

“We’ve blown through all the carbon budgets. We need to be moving off of all fossil fuels as quickly as possible.”

“Australia does not need any new gas,” Baxter adds. “Expanding the industry is not only irresponsible – it’s dangerous. The federal government must abandon its plans to expand gas operations and instead spend public money on scaling up clean, safe, and affordable renewable energy.”