A study from independent research consortium Researching Fracking in Europe (ReFINE) has found that data looking at the risks of leaking shale gas wells is “sparse”. It says current numbers show huge disparity in the safety of such wells.
The study, published in Marine and Petroleum Geology, found that previous research of oil and gas wells that were drilled over the last 100 years reveal highly variable well barrier and well integrity failure rates, ranging from 1.9% to 75%.
The researchers noted that this disparity was probably a result of the differences in the number of wells included in each study, their age, design and the geology they penetrate.
Whilst information on well failure is made publicly available in the US, this isn’t the case across Europe. As a result, assessing the likelihood of pollution risks due to structural failure of the well casing is difficult.
The research also raised questions around responsibility for wells in the UK. Of the 2,152 wells drilled onshore between 1902 and 2013, up to 100 are ‘orphaned’, with no firm being responsible for them. In total, 53% of the wells were also drilled by a company that no longer exists or which has been taken over or merged.
Prof Richard Davies of Durham University, the ReFINE project leader, said, “The findings of this research confirm that well barrier failure and well integrity failure in hydrocarbon wells is an issue and publicly available date in Europe on this seems to be sparse.”
The report recommended that a periodic survey of active and abandoned well should be done in order to assess the impact of shale gas exploration. It also argues that this data must be made publicly available.
The government has backed fracking and in December 2013 set out measures to provide certainty to shale gas investors. It also announced that it was exploring the possibility of “large scale shale gas production” by the 2020s.
Experts have recently warned that this focus on shale gas could threaten renewable investment and long-term energy security in the UK.
In response to the report, Lawrence Carter, energy campaigner at Greenpeace, said, “Government ministers and shale gas executives consistently argue that we don’t need to worry about fracking as we’ve been drilling onshore for years. But this report reveals they haven’t got a clue about the number of onshore well failures because the data doesn’t exist.”
He added that even if the data were available fracking is “much more intensive” and as a result poses higher risks. “If they want to gain the public’s trust, proponents of fracking need to base their arguments on evidence rather than spin,” he concluded.
The controversial method of fracking has been subjected to a number of conflicting reports. Some have suggested that fracking could impact on health because it releases hormone-disrupting chemicals and could result in birth defects. Researchers have also raised environmental concerns around water contamination and increasing the likelihood of earthquakes.