Fracked or fiction: so what are the risks associated with shale gas exploitation?
Durham University leads the ReFINE (Researching Fracking In Europe) project and is carrying out independent research from a neutral stance in order to help provide information for members of the public, politicians, industry and academics around Europe.
The presentation starts with an overview of how shale gas and oil extraction is carried out using the fracking process.
Three major issues of public concern are then addressed.Firstly, can the process of cracking rock underground lead to water contamination? Secondly, can fracking cause earthquakes? Thirdly, could the wells that we drill to extract shale gas leak, and what can we learn from the history of drilling in the UK to date?
The key messages are:
(a) that fracking has caused earthquakes in the past, but very few have been of sufficient magnitude to be felt, and there are several more familiar industrial processes which generate bigger quakes;
(b) hydraulic fracturing itself is very unlikely to cause water contamination because fractures are not tall enough to go from the shale layer at 2-3 km depth to the aquifer just below the surface;
(c) that poor sealing of wells is a mechanism for contamination of the environment, as has been documented in a small number of cases in the USA.
In the UK we have 2152 onshore wells drilled between 1902 and 2013, only a small percentage of which are in active use. Although these are monitored, information on well leakage is not in the public domain. The majority of the wells in the UK are disused (known as ‘abandoned’), and have been sealed and the land reclaimed. No jurisdiction that we know of, including the UK, monitors such abandoned wells. More data in the public domain on well leakage statistics would allow the resultant risk and potential impact to be better understood and managed.
Watch the Lecture:
Speaker
Richard Davies (University of Durham)
Professor Richard Davies is a petroleum geologist and Professor of Energy at Durham University. He spent 8 years in the oil and gas industry in the UK and USA before becoming an academic. From 2009-2013 he was Director of Durham Energy Institute and now he is Dean of Knowledge Exchange and Impact. He has published over 80 research papers and since 2011 his research has focused on building an unbiased, independent evidence base on the environmental risks of shale gas and oil exploitation, dealing with issues such as the risks of water contamination, earthquakes and the integrity of hydrocarbon wells.