With British Prime Minister David Cameron over the prospects of unconventional gas drilling in the UK that the country is “going all out for shale” and a rise in citizen protests, researchers are looking for information with which to evaluate potential risks. And with a lack of available data in the UK, those researchers are looking elsewhere – including Pennsylvania. And what they’ve found are very troubling well failure rates and violation records.
This story on the study says:
The researchers focused on well failures, in which the cement, steel casing or valves failed to contain the oil, gas and drilling fluids. It noted the difference between internal failures, where gas, oil or other chemicals did not leak into the wider environment and external failures, where leaks did enter rocks, water acquifers or the air...One dataset highlighted found that 8,030 fracking wells targetting the Marcellus shale in Pennsylvania were inspected between 2005-2013 and 6.3% (506 wells) were reported for internal or external well barrier failures...
Analysis of another Pennsylvania dataset of 3,533 wells between 2008-2011 found that one-third were issued with environmental violation notices. These were mostly for surface water contamination, land spills or problems with site restoration. But 2.6% (91 wells) suffered some internal or external well barrier failures, including four blowouts.
Well integrity is fundamental to safe shale gas development. Failure is not an option. The failure rates found in this study – as well as the violation rates – are unacceptable and should not be tolerated.