Fracking: why it’s fracking fluid that’s the grey area
Fracking is a highly contentious term for a highly contentious practice. Environmentalists gained the upper-hand with the verb ‘frack’: harsh, cacophonous, and the euphemism for campaign posters the world over. The industry prefers the term ‘hydraulic fracturing’, with its clean, efficient, and neutral tone. Which is better? Is fracking as bad as it seems?
First, the basics: fracking is the process of fracturing rocks containing natural gas using a pressurized liquid, in order to make extraction commercially viable. Water, sand and a concoction of other chemicals are forced under high pressure into a well, which causes the sedimentary rock beds to fissure, releasing the natural gas.
the past growth and forecast of oil and fracked gas in the USA, showing the importance of natural gas to the US economy; the politicization of the word ‘frack’
The economic arguments in favour of fracking:
The benefits of fracking carry important economic weight, explaining why, despite its negative publicity, the USA have assimilated it into its energy sector. Fracking’s first trump card (like Oil sands for Canada) is the lure of energy independence. In 2015, hydraulically-fractured wells yielded 67% of natural gas in the USA, accounting for 19.3% of all US-consumed energy, and led to a decrease in its oil imports. Hence, the USA can now claim independence in its energy sector, despite still relying on oil imports for transport. This has huge geopolitical clout: the USA is no longer influenced to such a great extent by OPEC, nor will action in the Middle East be as dominated by oil-ties. The energy security is often also linked to global economic health, and the USA is forecast to become a net exporter of natural gas in the immediate future as more wells are made viable by improvements in fracking.
Secondly, fracking lowers energy prices; natural gas prices in the USA have fallen 47% compared to projected 2013 prices in a scenario without fracking, cutting $200 per year off the energy bill of every gas-consuming household. With fuel poverty a prescient issue, this is an important piece to the puzzle, and a significant motivation in the UK.
Thirdly, fracking employs people. Nobody can agree on a figure for total US employment in the USA derived from fracking, with studies yielding different results, depending on the degree to which indirect employment links are included. What is certain is that it is in the hundreds of thousands, and linked to a ripple-effect whereby even non-fracking states benefit. The US Chamber of Commerce ‘s 21st Century Energy Institute places it at 1.7 million, billed to increase by 3.5 million by 2035; others suggest 600,000, and 725,000, with plain uncertainty the take-home message. However, whilst this money has created boom towns, centres of wealth which have largely benefitted migrants, complicating the picture.
Lastly, natural gas is much cleaner than coal, with reductions in sulfur dioxide and nitrous oxide emissions helping to reduce air pollution. The combustion of natural gas 50-60% less greenhouse gas emissions compared to coal, and fracked natural gas is touted as a way of weaning fossil-fuel economies off fossil fuels. Nonetheless, flaws exist in this argument: firstly, the emissions reduction is qualified by the fact that methane leaks at higher rates from natural gas wells than conventional oil wells. One article in Nature placed the leak of methane per fracked well at 3.6-7.9% of the total volume of natural gas in the well, compared to 1.7-6% in a traditional well. Some suggest that this might come close to offsetting the benefits of burning methane over coal, although the carbon footprint of the USA is falling. And despite nationwide improvements in air quality a coal-power declines, localised air pollution and benzene concentration in the air have increased near fracking sites.
Arguably, the largest issue in the fracking debate is water contamination. The problem with fracking is fracking fluid, often touted as water (90%) and sand (9.5%) – or a ceramic, known as a proppant, to hold fissures open in the rock. In reality, the remaining 0.5% is what counts. Slickwater chemicals are added to reduce friction (polyacrylamide); biocides to prevent microorganismal growth; acids, such as hydrochloric acid, to remove mud; oxygen-scavenging ingredients such as sulfates; surfactants such as 2-butoxyethanol, which leads to spleen, liver, and bone marrow lesions and anaemia; methanol; diesel, naphthalene; benzene, xylene, toluene, ethylbenzene; formaldehyde; radionuclides to track the movement of the fluid; gels involving borate to hold the proppant in suspension.
The appendix of the US-government analysis goes on, and on, and on; the US-government doesn’t even know whether it has an end because of a loophole enshrined in US law known as the Halliburton Loophole (2005). It prevents the US Environmental Protection Agency (EPA) from regulating fracking; it is the only industry exempt from the Safe Drinking Water Act.
In other words, fracking companies in the USA can freely inject carcinogens, radionuclides, toxic chemicals, and biocides into the ground without disclosing the products that they use. 29 prohibited carcinogens, air pollutants, and other hazard chemicals otherwise restricted were found in this US-government study of 2500 fracking fluids used.
Does it really cause contamination?
However, what remains controversial is whether fracking causes groundwater contamination. A 2016 study by a tenacious Stanford researcher (DeGuilio) revealed definitive methanol contamination in a Wyoming village of Pavillion, following complaints by local residents. Methanol, the most common fracking fluid component, is linked to permanent nerve damage and blindness. However, what the study revealed very clearly was the difficulty in assessing contamination; methanol – the simplest alcohol – is highly water soluble, alongside the majority of other compounds used in fracking. The study had to develop highly sensitive liquid chromatography to detect it, also noticing diesel within the contaminated water, with concerns that such contamination may go unnoticed despite testing. Hydrologically, the study suggested water had migrated vertically into aquifers, with anomalous ions found in the nearby water system. It led the EPA to conclude that fracking contaminates groundwater, a landmark step in establishing the environmental cost of fracking.
Nonetheless, many critics suggested that the study’s wider repercussions were limited because the particular well was shallow in comparison to the majority of fracking wellbores. Fracking’s proponents still cite the paucity of scientific literature with a correlation between water pollution and fracking; this is often seen as evidence that fracking leads to negligible contamination, although it is only now that long-term exposure can be studied. But, importantly, what has been recognised recently is that the fracking injection wells themselves are rarely the cause of groundwater pollution. Industry studies repeatedly show the integrity of their concrete-lined well-shafts; their focus is underground whereas the real risk of contamination is at the surface.
Blowouts and spills at the surface around the well-pad cause fracking fluid to leach into throughflow water at the surface, straight into nearby water systems. Moreover, fracking fluid (called flowback, or brine) often returns to the surface following injection, with one argument in the Nature suggesting this amounts to 20% of all fracking fluid; for some wells, the fluid must be extracted from the well, and then processed.
Dealing with waste water:
In Pennsylvania, flowback water has been treated in municipal sewage facilities, which are inadequate for removing the incredibly soluble and exotic compounds used in fracking fluid; in one stream studied in Pennsylvania, close to a treatment unit, chloride, bromide, and radium ions were found, and hydrocarbons present in the water were dangerously brominated. Even when the water is treated in specialist facilities, a sludge is still left: highly toxic, carcinogenic, and radioactive from the radium nucleotides, it still has to be removed, and in Pennsylvania, due to the unsuitability of the rocks for this, the sludge has to be trucked to Ohio for disposal, with associated vehicular emissions.
The dominant method of disposal is to re-inject the sludge into the ground into what are known as deep injection disposal wells, with the consequence of permanently removing water from the water cycle; although they are currently thought to have limited impact, these wells are likely to throw up long-term side-effects, despite their location well-below the depth of the water table. In some cases, companies have even illegally tipped their untreated brine into river systems, with one case involving 40,00 barrels tipped into a Delaware River tributary to avoid paying the costs of treatment.
Although pro-fracking groups compare the water usage in fracking to fractions of a percent of other industries (such as car-washing), the fact remains that fracking is a drain on water supplies, with horizontal well shafts using a larger volume of water than vertical wells, and unconventional deposits yet more. The EPA estimated that, in the year 2011, fracking used 70-140 billion gallons of water per year. In areas set to become drier and subject to droughts due to climate change, fracking could be an important cause of desertification. Furthermore, in areas with well shafts unsuitable for pipes, the water has to be trucked in, causing disturbance, noise and air pollution, and road degradation to communities nearby, which is one of the chief concerns with fracking in the UK.
Fracking has acquired a reputation for causing earthquakes, a phenomenon known as induced seismicity; the sedimentary rock can release seismic waves as the fracking fluid forces the seams of rock apart, or the water pressure can be the trigger to release a natural build-up of pressure. Although it might seem like an important consideration, these earthquakes only measure on seismographs as microseismicity (below 2.5 on the Richter Scale); they are hardly ever felt, and in cases where seismometers aren’t located above the fracture site, they are often never recorded.
Indeed, 98-99% of all induced earthquakes associated with fracking aren’t related to fracturing the rock to free up natural gas, but instead to wastewater disposal, according to the USGS. It is thought that fracking has an overall negligible effect on seismicity, although over half of earthquakes in the USA over 4.5 magnitude have occurred in regions which experience fracking-related activities, and long-term studies are needed to further evaluate seismicity. Nonetheless, a 2.3 magnitude earthquake following exploratory fracking in Lancashire, UK, led to the prophylactic suspension of drilling in that area.
So, is fracking good or bad? As an industry, it unquestionably needs regulation, a consequence which could prohibit the chemicals that are needed to make it efficient. Yet, surely, the answer at the end of the day is to invest in renewable energy sources using the money that is invested in fracking, equally employing thousands, and retaining the same energy independence, with a positive environmental legacy rather than squabble back and forth over the merits and dangers of fracking.