Hydraulic fracturing or ‘fracking’ has dramatically changed the energy sector in the US , allowing them to become the world’s largest natural gas producer and lessen its dependence on crude oil imported from the Middle East. But the question remains as to what environmental and public health cost? There are increasing numbers of reports that hydraulic fracturing can cause groundwater and surface water contamination, cause emission of volatile compounds, induce earthquakes/tremors and causes ecological damage. Many other countries, including Ireland, still need to decide whether they will follow the US and allow hydraulic fracturing on, or under, their soil.
Hydraulic fracturing is a unconventional gas recovery technique that involves pumping water-rich fluid into a borehole until the pressure at depth causes the rock to fracture. The shale gas revolution in the US has come about largely with the development of directional sideways drilling from the initial borehole. The fluid and gas mix is then pumped back to the surface. Take a look at this Youtube video for a better idea of how it works.
The detailed regional geology and subsurface depth of fracturing are two critical technical aspects that shale gas companies need to consider when conducting their work. These factors are also critical when it comes to potential environmental impacts. Coal bed methane fracking is generally considered to pose greater risks than more typical shale gas fracking since it occurs at shallow depths close to the water table. In addition, the US is deemed to have simpler geology and subsurface tectonics compared to most of NW Europe. In any case, the relative environmental health impacts and risks must be assessed based on the most up-to-date knowledge and research. Most would agree that these investigations should be performed by unbiased independent bodies that generate quality peer-reviewed data.
A recent 2016 study from Hays and Shonkoff published in the peer-reviewed journal PLoS ONE comprehensively assessed the peer-reviewed literature between 2009 and 2015 dealing with the environmental and health impacts of unconventional gas development. They found that 26 out of 31 (84%) public health studies found some public health hazard or risk; 40 out of 58 (69%) water quality studies found some evidence for water contamination and 40 out of 47 (87%) air quality studies found elevated air pollutant emissions. The authors highlight that almost all studies cite the need for additional work, and the need for quantitative epidemiological research on the health outcomes associated with the aforementioned risks.
The US EPA released its report on the potential impacts of hydraulic fracturing on drinking water supplies in 2016 (for its press release, click here, and for the report click on this link). Similar to the Hays and Shonkoff findings, the EPA found that there were significant data gaps and uncertainties and these limited their ability to make a full assessment of the impacts on drinking water supplies. The EPA did find that hydraulic fracturing can have an impact in certain scenarios. These impacts can be more ‘frequent or severe’ when it is conducted in areas with low or declining groundwater supply; when accidental spills occur; when wells have inadequate ‘mechanical integrity’; when hydraulic fracturing process wastewater is discharged to surface waters; when this wastewater is stored inadequately and leaches into water supplies; and when drill fluids are directly injected into groundwater reservoirs.
Healy (2012, Irish EPA report) concluded that groundwater contamination from shale gas hydraulic fracturing occurs primarily when there are poor cement jobs on well bore casings close to the surface and also from leakages from hydraulic fracturing-related waste water above ground. The quality of the casing and cement job are also among the most important factors that limit the release of volatile organic and inorganic compounds in water and the atmosphere. Besides poor practice, negligence and accidents at the surface, another important factor determining the environmental risk that has emerged from research is the operational depth below the surface (for example the enhanced risks associated with coal bed methane hydraulic fracturing). Other risks include: the release of toxic chemical additives; blow outs from pressure release occurring in the direction of the (or nearby) well bore; ecological damage and altered hydrology from water bodies use for water extraction; and environmental/health impacts from associated infrastructure and traffic arising from hydraulic fracturing activity.
The debate for and against hydraulic fracturing in Ireland has been ongoing over the past number of years. The controversial activity has already been banned in France (2011), Bulgaria (2012) Germany (2016), the Australian state of Victoria. The Netherlands placed a moratorium on hydraulic fracturing until 2020 and Scotland will decide whether to ban or lift its moratorium by mid-late 2017, based on evidence gathered over the past year and a public consultation period. It appears now that Ireland may be narrowing in on a conclusion to the debate that has been ongoing over the past few years. The Prohibition of the Exploration and Extraction of Onshore Petroleum Bill 2016 was supported by the Dáil in October and the EPA provided a detailed report to the Joint Committee in December. The Joint Committee is now considering this bill, the EPA’s report, and the public’s consultation until 10th February.
The EPA report concluded that many of the activities associated with hydraulic fracturing could be achieved in Ireland while protecting the environment and human health by using best practices and applying current regulations. However, the impacts associated with groundwater contamination by failed borehole casings, groundwater contamination from migration of pollutants through fractures created by hydraulic fracturing, and long-term leakage of methane from capped wells following cessation of production lack insufficient data. The EPA therefore concluded that hydraulic fracturing should not be authorised without additional information on these impacts. In addition to the EPA report, the Sustainable Water Network (SWAN) published a report which assessed the potential impacts of hydraulic fracturing on Ireland’s water resources. Among a number of risks mentioned above, SWAN found that existing legislation would be inadequate to regulate hydraulic fracturing activities and protect the environment, and are not consistent with EU and Irish leglisation to protect water resources. The SWAN report concluded that hydraulic fracturing should be banned for these reasons and by invoking the precautionary principle,
“Applying the philosophy of the precautionary principle … in conditions of uncertainty, decision-makers should prevent potentially serious or irreversible environmental harm. Large uncertainties remain about many areas of shale gas operations, and the effects of environmental degradation could yield a deterioration in the WFD status of water bodies in the proposed regions”
There is no doubt that we need more data and research regarding the risks to groundwater, surface water, agriculture and the biosphere before hydraulic fracturing should be authorized in Ireland. In any case, it appears that the economic benefits may be minimal. Evidence from Scottish research estimated that between 100 million GBP and 4.6 billion GBP would be added to the Scottish economy between now and 2062 (BBC new report here). While opinion was divided and this is quite a range, these figures appear to be relatively low for a 4 decade period. This would likely be the case in Ireland also. Added to that, the depth of deposits of interest and the complex geology compared to the vast US basins, means that hydraulic fracturing would invariably be much more complex and risky (for gas companies and the public) in Ireland.
Finally it has been argued that investing in hydraulic fracturing and increasing our reliance on non-renewable energies now, especially considering the recent COP21 Paris Agreement (see previous blogpost), is a step in the wrong direction when it comes to mitigating climate change and the projected future energy portfolios for most countries. Thus, overall I agree with the conclusions made in the EPA and SWAN reports that the precautionary principle applies here and that hydraulic fracturing should not proceed in Ireland at present. This should remain the case until we have significant evidence telling us that we can minimize adverse impacts on our environment and public health and if we can demonstrate that it is a viable step for Ireland towards a sustainable future energy mix that can help mitigate climate change. It remains to be seen how our government will act in the coming weeks.