The environmental risks of hydraulic fracturing in conventional and unconventional wells are ground and surface water contamination, water resource depletion, releases to air, traffic, land take, noise, visual impact and seismicity, which are typically addressed in environmental impact assessments for fracking activities. The causation of earthquakes with any significant impact or fractures reaching and contaminating drinking water, were "very low risk" if adequate regulations are in place. in December 2013 covers many of the environmental issues that would arise were the shale gas industry to become highly developed. The
British Geological Survey is involved with
environmental monitoring. In October 2014, EASAC stated that: "Overall, in Europe more than 1000 horizontal wells and several thousand hydraulic fracturing jobs have been executed in recent decades. None of these operations are known to have resulted in safety or environmental problems". In October 2016, Amec Foster Wheeler Infrastructure Ltd (AFWI) compared the environmental impacts and risks of unconventional high volume hydraulic fracturing with conventional low volume hydraulic fracturing. The study found that volume of fluid injected and flowback were the only significant differences between conventional low volume and unconventional high volume hydraulic fracturing and that the impacts and risks for high volume hydraulic fracturing scaled up for land take, traffic, surface water contamination and water resource depletion.
Air In February 2016, a study by the ReFINE consortium funded by the Natural Environment Research Council (NERC),
Shell,
Chevron,
Ineos and
Centrica, found "substantial increases over the baseline""in local air quality pollutants", during the short-duration high-traffic phase which includes the delivery of hydraulic fracturing equipment, proppant, water, as well as the removal of flowback from the site. According to ReFiNE, these short-duration increases have the potential to breach local air quality standards. The industry group UKOOG criticised the ReFiNE study for failing to take into account that water for hydraulic fracturing fluid might be brought in by pipeline, instead of being transported by truck. In October 2016, Amec Foster Wheeler Infrastructure Ltd stated that the overall environmental impacts from low volume hydraulic fracturing to local air quality and global warming are low. Local air quality is impacted by dust and
SO2 and
NOx emissions "from equipment and vehicles used to transport, pressurise and injection fracturing fluids, and process flowback", while "Emissions of CO2| from the equipment used to pressurise and injection fracturing fluids, and process flowback." contributes to
global warming. In January 2015, the
British Geological Survey released national baseline methane levels, which showed a wide range of readings Poor surface well sealing, which allows methane to leak, methane was identified in the Royal Academy of Engineering report as a risk to groundwater. This was incorporated into the Infrastructure Act 2015 with a requirement that monitoring takes place 12 months before fracturing. The
Chartered Institution of Water and Environmental Management (CIWEM) have been involved with evaluating the potential water impacts of hydraulic fracturing.
Groundwater contamination Both low and high volume hydraulic fracturing "involve storing and injecting large quantities of chemicals". Any surface spill therefore has "the potential to penetrate groundwater". The likelihood of low volume and high volume hydraulic fracturing contaminating groundwater by surface spills of stored chemicals is rare, however the risk and consequences are moderate. To mitigate the risk, the Environment Agency requires chemical and fluid proof well pads. --END---> The 2012 joint Royal Society and Royal Academy of Engineering report indicated that the distances between potable water supplies and fractured formation in various US shale plays is large, meaning the risk of contamination is very small. No cases of pollution by this route have been identified. Another 2013 paper from ReFine indicated the potential for surface gas leaks from
abandoned wells Water use Water use is regulated by the
EA (England), the
SEPA (Scotland), the
NIEA (Northern Ireland) and
NRW (Wales) to ensure environmental needs are not compromised. Water companies assess how much water is available, before providing it to operators. The amount of water abstracted nationally is at around 9.4 billion cubic metres. In 2015, the EA indicated that water usage at a peak level would be 0.1% of national use and hydraulic fracturing may use up to "30 million litres per well". Drier areas, such as south-east England, are concerned about the impact of hydraulic fracturing on water supplies.
Seismicity Microseismic monitoring The hydraulic fracturing process creates a large number of microseismic events, which require monitoring. In December 2015, the
Centre for Research into Earth Energy Systems (CeREES) at Durham University published the first research of its kind, prior to "planned shale gas and oil exploitation", in order to establish a baseline for anthropogenic,
induced seismic events in the UK.
Cuadrilla, Lancashire In May 2011, the government suspended Cuadrilla's hydraulic fracturing operations in their Preese Hall-1 well in Lancashire, after two small earthquakes were triggered, one of magnitude M 2.3. The largest coseismic slip caused minor deformation of the wellbore and was strong enough to be felt. The company halted operations to await DECC guidance on the conclusions of a study being carried out by the
British Geological Survey and
Keele University, Cuadrilla pointed out that a number of such small-magnitude earthquakes occur naturally each month in Britain. Cuadrilla commissioned an investigation into the seismic activity, which concluded that the tremors were probably caused by the lubrication of an existing
fault plane by the unintended spread of hydraulic fracturing fluid below ground. In 2012, a report on hydraulic fracturing produced jointly by the
Royal Society and the Royal Academy of Engineering noted that earthquakes of magnitude M 3.0, which are more intense than the larger of the two quakes caused by Cuadrilla are: "Felt by few people at rest or in the upper floors of buildings; similar to the passing of a truck." In February 2014, following the small seismic event in the Preese Hall 1 well, and much research, the DECC issued a statement on earthquake risk. Up to August 2016, there were two cases in the UK of
fault reactivation by hydraulic fracturing that caused induced seismicity strong enough to be felt by humans at the surface: both in Lancashire (M 2.3 and M 1.5). In October 2018, more earthquakes were recorded in
Lancashire, including two tremors of 0.8 magnitude which obliged
Cuadrilla to call a temporary halt on the drilling operations. In 2019 a peer-reviewed paper was published under the joint authorship of Cuadrilla and Bristol University authors. It described how detailed microseismic monitoring, such as at Preston New Road, could help an operator to assess the seismic risk, and thus make proactive decisions to the mitigate induced seismicity in real time. But the proactive mitigation failed, because in August 2019, after a series of minor tremors and pauses in fracking under the traffic light system, a local magnitude 2.9 earthquake was triggered, and Cuadrilla was obliged to suspend its fracking.
Subsidence There is no documented evidence of hydraulic fracturing leading to subsidence.
Insurance In an answer to questions from the 'Lets talk about Shale' initiative, run by
Westbourne Communications for the industry body, UKOOG, they have stated "According to the Association of British Insurers there is, at present, little evidence of a link between shale gas and property damage, and they are not aware of any claims where seismic activity as a result of fracking has been cited as a cause of damage. Damage as a result of earthquakes, subsidence, heave and landslip are all covered, in general, under buildings insurance. Insurers will continue to monitor the situation for the potential for fracking, or similar explorations, to cause damage." It was reported in early 2015 that farms would not be covered by issues that may arise due to hydraulic fracturing. A clarification by the insurer indicated that this would only apply to a farmer that permitted this on their land. Surrounding farms would be covered. In March 2017, the
Chartered Insurance Institute (CII) released a report by the CII Claims Faculty New Generation Group, which explored the
Insurance implications of fracking. The authors examined the "key perils associated with fracking such as earthquakes, explosions and fire, pollution, injury and death", and found that while "most insurances policies" provided "cover for these risks", "fracking will pose additional complications around liability". The authors also considered that if widespread fracking were to lead to increased claims, "then insurers may have to consider how they underwrite this emerging higher-risk group". The authors recommended: working together within the insurance profession "to monitor and discuss the issues" while remaining "open and transparent about the risks of fracking", and; working with the "energy industry and the government" "to reduce the likelihood of potential risks occurring". The CII emphasised that "insurers need to be prepared for claims in the event of a fracking-related loss and consider policy wordings with increased fracking in mind".
Public health If the Minerals Planning Authority determine that public health will be significantly impacted, the Director of Public health is consulted so that a "health impact assessment" can be prepared. The Environment Agency then uses the health impact assessment when considering the "potential health effects" during their "permit determination" In 2015 the health charity
Medact published a paper written by two public health specialists called 'Health & Fracking - The impacts and opportunity costs', which reviewed health impacts of hydraulic fracturing and suggested a moratorium until a more detailed health and environmental impact assessment could be completed. UKOOG criticised Medact's understanding of UK regulations and said they had not declared that one of its consultants, who was standing for parliament in the 2015 general election, had a
conflict of interest.
The Times journalist Ben Webster also criticised Medact for not declaring one of their consultant's conflict of interest and reported that the Medact director had not realised that this consultant was also an anti-fracking candidate. MedAct published a response to these criticisms. The content of the Medact Report 2015 was referred to by many objectors in the June 2015 Public reports pack for the Lancashire County Council Development Control Committee. Lancashire County Council were uncertain how much weight to attach to the Medact report due to "questions from some quarters" about the objectivity of the report based on association of two its contributors with campaigns relating to shale gas. In 2016, Medact released an updated public health report, citing health risks from shale gas development and calling upon the government to "abandon its shale gas plans". ==The fracking debate==