Viewpoints: Fracking’s risks and benefits
Fracking was halted in 2011 after some minor earthquakes near Blackpool, in north-west England, were attributed to test wells being drilled
5 January 2013
The UK government recently lifted its moratorium on the controversial process known as hydraulic fracturing, or fracking. The technique involves pumping fluids into a well to recover natural gas from shale rock.
However, fracking has been linked to some minor earthquakes, and there are concerns about its possible environmental impact. So what benefits could hydraulic fracturing bring, and how concerned should we be?
Prof Richard Davies, of the Durham Energy Institute, says
During the recent debate on fracking technology in the UK, we may have been distracted from considering some of the real issues in developing our shale gas reserves.
The much-popularised link between fracking and contamination of water supplies remains unproven and our research at Durham University shows the chances of it ever happening can be dramatically reduced if the fracking is carried out at vertical distances greater than 600m below the drinking water aquifer.
We also find that fracking has only caused three reported examples of felt earthquakes (one of which was in Lancashire), but there have been hundreds of thousands of fracking operations.
A real issue is that for the UK to produce enough gas for it to make a difference to our indigenous supplies requires a lot of wells – many more than are typical for conventional gas reservoirs.
Therefore the long-term integrity of boreholes and the cement used to seal the boreholes and prevent leaks will be of critical importance.
The risks appear to be tiny – of thousands of shale gas wells drilled in the USA, only a handful have reported problems with leakage and all were successfully sealed by subsequent work. But one leaking well is one too many.
The UK does not have an abundance of rigs and fracking equipment, so a rapid growth in shale gas production is unlikely.
If the social acceptance is there so that enough wells can be drilled, then the long-term integrity of the boreholes is a real issue that will need to be a priority for shale gas companies and regulators.