By Alexander Moss
Offshore fracking has been used since the 1970s to extract gas from the gas rich areas concentrated in the south of the North sea. Reduction in the cost to frack, due to technological advancement, coupled with a high oil price meant that less economically viable onshore fracking became viable in the 21st century. Protests to fracking have existed nearly as long as the practice itself, and are spearheaded today globally by Greenpeace. In the UK, anti-fracking is championed by the Green Party and Labour, and by the SNP in Scotland, all committing to a blanket ban on fracking. Despite protests in the 1990s the government sold the rights to frack onshore in the UK, and in 2010 after a lengthy legal process, in my home county of Lancashire, fracking was initiated. However, following an earthquake measuring 1.1 on the Richter Scale in October 2018 the government halted the practice at the site. The environmental and social impacts of the industry were thrust into the forefront of politics once again.
The Shale Environmental Regulator Group (SERG) was set up to better coordinate the regulation of shale gas well sites, in an attempt to reduce the effects of fracking. It brings together the regulatory activity of the Environment Agency, Health and Safety Executive, and the Oil and Gas Authority working as a coherent, single face for local authorities and industry. SERG regulates the industry under strict regulations, protecting areas of outstanding natural beauty and groundwater, as well as regulations on the seismic activity induced by fracking, and the disposal of waste hydraulic fluids. It is illegal to frack in National Parks, the Broads, areas of outstanding natural beauty and World Heritage sites. Protected groundwater source areas are well defined and are stricter for abstraction points which supply water for domestic or food production purposes.
SERG aims to regulate and reduce the levels of seismic activity induced by fracking. Seismic activity induced by the conventional oil and gas industry are well known, and the impacts are generally minimal. However, fracking is much more likely to cause seismic activity due to the procedure involved: the injection of high pressure water, sand and chemicals into a source rock. The Royal Society and Royal Academy of Engineering have said that the level of seismicity brought on by hydraulic fracturing is likely to be even smaller than mining. It is now being widely accepted that the magnitude of seismicity induced by hydraulic fracturing would be no greater than 3 (felt by few people and resulting in negligible, if any, surface impacts). In 2011, at the Blackpool site in Lancashire there were two tremors recording 1.5 and 2.3 on the Richter scale, a report published by the Department of Energy and Climate Change in conjunction with the British Geological Society concluded that the seismic activity was fracking induced. The report also concluded that the earthquakes were due to pre-existing stored energy on inactive faults in the region and that further small earthquakes could not be ruled out. The risk from these tremors is low, and structural damage is extremely unlikely.
As a result of this activity in 2011 new controls have been introduced to address the possibility of any seismic risks. The ‘Regulation of Fracking-Induced Seismic Activity 2013’ requires operators to ensure that wells are not drilled into, or close to, pre-existing faults which could cause earthquakes. Real time seismic monitoring is also required before and during extraction and a traffic light warning protocol is employed. If any site records a magnitude 0.5 on the Richter scale operations will be halted and pressure decreased immediately, this is well below the threshold of being felt at the surface, magnitude 3.
Seismic activity induced by fracking is not exclusive to the UK; it is key to examine how fracking has affected other regions of the world. The US has the longest and most well established onshore fracking industry, including in Texas and Pennsylvania. Pioneering hydraulic fracking of the Barnet Shale in Texas commenced in 1999, following its discovery in 1981 by the Mitchell Energy company. Mitchell Energy was at the forefront of the industry, and oversaw the beginning of the boom of fracking in the US. The Fort Worth Basin, where Barnet Shale is fracked, is a failed arm of an opening ocean basin, that ceased to be highly tectonically active 300 Million years ago, and is today a relatively stable block of the crust. Typically the region has seen earthquakes of magnitudes less than 1.0 induced by fracking. However, the extraction of natural gas by fracking in the Fort Worth Basin of central Texas was in near ideal conditions. Texas’ climate also aids in the extraction of hydrocarbons as the aridity lowers the water table, reducing the likelihood of polluting ground waters. The sparsity of population in Texas means that pollution, if any, affects fewer people too.
It would be fairer to compare the potential for shale gas extraction in the UK, with the exploitation of the Marcellus and Utica shales in another prominent fracking region of the US, the Pittsburgh tri-state area. Covering parts of Pennsylvania, Ohio, and West Virginia, the tri-state area sits on over 4.5km of sedimentary rock, deposited in a basin controlled by faults in the basement rock. Later plate tectonic interactions which formed the Appalachians also uplifted, and inverted, the basin, meaning the rocks are now at a shallower depth than they had been at maximum burial. The tri-state area experienced very few earthquakes prior hydraulic fracking. However, between 2013 and 2015 the Ohio quakes took place about 70 miles west of Pittsburgh, the largest of which was a magnitude 3.0, the biggest earthquake ever caused by fracking. According to a study published January 2019 in the Bulletin of the Seismological Society of America, the fracking triggered earthquakes on a hidden fault in ancient crystalline rock beneath a natural gas well. There is evidence that seismicity induced by drilling the Utica shale at a depth of 1.8km “can also occur in faults inside the sedimentary section itself, [raising] a new level of concern,” said Professor Andy Nyblade of Penn State Department of Geosciences.
Similar to Northern England, Pittsburgh is in a temperate climate, where groundwater contamination is a larger threat. There have been multiple reported cases of methane polluting water supplies in the Pittsburgh area. The activation of faults increases the threat of contamination as it opens up other channels for pollutants to migrate along. Activation of inactive or hidden faults adds a factor of uncertainty, because not all faults are expressed at the surface or visible in subsurface surveys. The result is unpredicted contamination that even regulations could not mitigate.
Pittsburgh draws comparisons socio-economically, to the North West of England situated in the rustbelt, having a history heavily intertwined with the steel industry and its decline. Similarly, the North West of England shows its heavy industrial past, including mining, mills and rail works, which have equally seen decline, particularly since the 1980’s.
Pittsburgh and Pennsylvania have seen an economic upswing since industry returned, owed not only to the investment of the fracking industry and related petrochemical refinement, but also to the new international port, exporting natural gas to afar as Japan. Matt Mehalik, executive director of the Breathe Project, a local nonprofit working to reduce air pollution in Pittsburgh, said “Here we go again. It’s like we’re going back on a bender, doing things that we know are bad for us. And yet it’s happening. It’s just an insane economic development strategy.”
Couple this with the fact that scientists are issuing increasingly severe warnings about the impacts of climate change and the need to rapidly reduce our dependence on fossil fuels, the fracking boom in the US is moving in precisely the wrong direction, and should not be mirrored here in the UK. All for the sake of a boom and bust economic cycle of heavy industry, that leaves communities with fracking induced earthquakes and contaminated drinking water.
Alexander Moss is a 3rd year undergraduate studying for a Masters of Earth Sciences at St Edmund Hall, Oxford. This is his first journalistic piece and he hopes to submit more pieces in the future. Alex has dreams of one day living a subsistence lifestyle in Norway.
Art by Sapphire Vital
If you like what you've just read, please support Anthroposphere by buying one of our beautifully designed physical copies here. All proceeds go towards printing, designing and maintaining our publication, and your contributions will help keep our climate journalism interdisciplinary and accessible for all.