What is fracking? Fracking – or hydraulic fracturing – is a means of extracting natural gas from sedimentary rocks such as shale. The process involves drilling horizontal wells deep into underground rock and pumping in a mixture of water, sand and chemicals at high pressure.
The mix fractures the rock and creates and maintains openings that allow the gas to seep out into the well for collection. The practice has been successful elsewhere but has also courted plenty of controversy. The late US businessman George P Mitchell is regarded as one of the main pioneers of fracking.
Why are we talking about it?
Shale rich areas of Ireland, such as Fermanagh, will soon undergo test drilling which ultimately could see the locations transformed into shale gas fields. Australian resources firm Tamboran, which has been awarded a licence by the Northern Ireland Executive, has until the end of September to drill exploratory boreholes near Belcoo in Fermanagh to collect samples.
Should the tests show commercially viable levels of shale gas, further extraction is likely in the future but additional approval would be needed from the authorities for this to go ahead.
Why are they looking in Ireland?
The natural resource net is being cast wider as oil and gas supplies become increasingly scarce and more expensive to access. There are also concerns about energy security given political upheaval in resource-rich areas such as the Middle East and Russia. Exploration firms are keen to find new resources to bring to the market and governments want to ensure their energy needs are met. What have they found here?
Shale gas has been detected in an area known as the Northwest Ireland Carboniferous Basin, which comprises parts of counties Leitrim, Roscommon, Sligo, Cavan, Donegal and Fermanagh.
Exploration firm Tamboran estimates the Fermanagh site has the potential to yield up to 2.2 trillion cubic feet of shale gas, an amount it says could provide 50 years supply for Northern Ireland at current usage rates. The value of such a yield has been estimated at up to $50 billion.
Who benefits?
Some of those involved in fracking say the process could deliver security of energy supply in Ireland for decades, provide thousands of jobs directly and indirectly and boost tax revenues.
Increased supply and easier access to it should lead to cheaper energy costs, as it would lessen the reliance on imported fuels, but the truth of this remains to be seen. The associated jobs and activity are seen having positive spin-off effects by increasing spending, or at least spending power, in the local economy.
The companies involved in fracking would obviously expect a return on their investment. The burning of natural gas is considered less harmful to the environment than coal and oil. Former minister for energy Pat Rabbitte said the "shale revolution" had been a "game changer" in the US by having a positive effect on competitiveness in the economy.
What’s the catch?
Opponents of fracking say that because of the intense nature and depth of shale gas drilling it can cause a wider range of negative effects than conventional gas extraction for the environment and those living near drilling sites.
Concern has been expressed about potential gas leaks, contamination of underground water reserves (given wells may pass through them or gas could infiltrate them), air pollution and even small earthquakes due to its subterranean nature.
Questions have also been raised about the sheer volume of water that needs to be used in fracking. These factors have led to worries about the impact the practice could have on sectors such as tourism and food production.
Do they have a point?
The studies carried out on fracking have suggested different things about its impact on the environment. Some say the risk of water sources being contaminated was no higher with fracking than other drilling processes, and that most pollution was due to mistakes made at ground level such as spillage of waste water.
Others say that emissions released during the process can cause headaches and breathing problems in people living near fracking activity and that drinking water near drilling sites in Pennsylvania in the US had increased levels of methane, ethane and propane.
A study by Public Health England, an executive arm of the British Department of Health, last year said shale gas drilling was safe if properly run and regulated and that fears groundwater would be contaminated are "unlikely" to be realised.
During a visit to Ireland, Prof Daniel Schrag, a Harvard University academic who has advised US president Barack Obama on environmental issues, said the benefit of "fracking" for shale gas was that it provided a "plausible alternative to coal".
"The problem with shale gas is local environmental hazards from the impact of drilling," he said. "It's not that much worse than conventional gas. Either way, it's a dirty business – not pretty – and there is always a risk of accidents." Where is it happening now?
The US is home to much fracking activity, including in states such as Texas, West Virginia, Arkansas, Colorado and Pennsylvania.
Fracking also takes place in countries such as Canada, New Zealand, Poland, Germany, Australia and South Africa. The British government is keen to see fracking activity but is currently facing a backlash against the practice from communities where drilling is expected to take place and environmental groups. The practice has been banned in France and Bulgaria.
What happens next here?
No decision will be made on the future of fracking in the State until after a wide-ranging study by the Environmental Protection Agency is completed in 2016. Some 1,356 submissions were received by the EPA following a public consultation period on fracking, the majority of which were opposed to the practice.
During his term as minister for energy, Mr Rabbitte said the ultimate goal of the Government was to maximise the benefits to Ireland of its indigenous oil and gas resources but he said it must also ensure that extraction was conducted safely.
He said that under both Irish and European law it is not possible to allow any project to proceed unless it can objectively be decided, following assessment of the evidence, that it would not have an unacceptable environmental or social impact.
However, he did say that the nature of the debate so far has tended to exacerbate health and environmental concerns associated with the process. It remains to be seen if his successor Alex White feels the same.
