Fracking operation may restart
A gas drilling operation halted after triggering earthquakes near Blackpool is likely to be restarted with rigorous controls aimed at preventing public alarm, it has been revealed.
The company involved has accepted stringent recommendations from Government-commissioned experts who say hydraulic fracturing should be allowed to continue at the Preese Hall well in Lancashire.
One of the provisos is that even a tremor too small to be noticed above ground should result in an immediate shutdown. Remedial action would then have to be carried out before work could be resumed again.
The independent report also calls for careful monitoring of the site using arrays of seismic sensors and steps to ensure excess pressure cannot build up beneath the ground. Hydraulic fracturing, or "fracking", involves injecting high pressure water and chemicals into shale rock to release trapped natural gas.
Well operator Cuadrilla Resources estimates that the Bowland Basin prospect site in Lancashire contains as much as 200 trillion cubic feet of gas. Even if only a fraction of this can be extracted, it still represents a very significant energy resource.
On April 1 and May 27 last year, two small earthquakes - of magnitude 2.3 and 1.5 - occurred in the Blackpool area. No damage was caused, although a number of people called the police to report shaking. After a second tremor was linked to fracking, operation of the Cuadrilla exploration well was halted.
The report, commissioned by the Department of Energy and Climate Change (DECC), confirmed that the earthquakes were caused by fracking taking place in a geologically stressed and vulnerable area. Its authors said further fracking-induced earthquakes were possible. Even though these would be small - no higher than around magnitude three and unlikely to cause structural damage - the experts added: "Such an event would be strongly felt by people within a few kilometres from the epicentre and could cause some alarm."
Environmental group Friends of the Earth remains strongly opposed to fracking for shale gas. Executive director Andy Atkins said: "We don't need earth tremor-causing fracking to meet our power needs - we need a seismic shift in energy policy."
Cuadrilla chief executive Mark Miller said: "We are pleased that the experts have come to a clear conclusion that it is safe to allow us to resume hydraulic fracturing, following the procedures outlined in the review. Many of today's recommendations were contained in the original expert studies we published in November last year, and our supplementary information sent to DECC in January. We have already started to implement a number of them in the pursuit of best practice."
A DECC spokesman said: "No decision has been taken on whether to allow fracking to resume at Cuadrilla's sites in Lancashire. We are grateful to the authors of the report and have launched a call for evidence to give people a chance to express their views on the report."
