The shale gas company, Cuadrilla, is to allow more fluid to come back to the surface after fracking, in an attempt to tackle the problem of earth tremors. It will also seek to raise the threshold on the magnitude of tremors at which fracking must stop.
The news came in a statement overnight from one of the Cuadrilla’s main investors, the Australian mining company, A J Lucas. AJ Lucas statement
Cuadrilla has confirmed that the statement is accurate but has declined to comment or add anything to it.
A series of 36 small and micro tremors have been recorded since Cuadrilla began fracking at its site at Preston New Road near Blackpool on 15 October 2018. DrillOrDrop tremor tracker
On four occasions, the company stopped fracking operations at Preston New Road because the magnitude of the tremors reached the threshold in the regulations, known as the traffic light system.
The statement, from the A J Lucas chairman, Philip Arnall, said the seismic threshold of 0.5 ML (local magnitude) was regarded as “overly conservative”.
But he said Cuadrilla was “working on the assumption that this constraint will not be altered for the current hydraulic fracturing operations”. The energy minister, Claire Perry, said last month it would be “foolish” to change the threshold at the moment.
Mr Arnall said Cuadrilla had therefore devised a work-plan to “optimise fracking and well performance” that allowed it to operate within the 0.5 ML threshold. He gave the following summary:
“it will involve a greater flow-back of fracturing fluid between fracturing stages by lengthening flowback periods and increasing the sand to water ratio in the fluid composition.”
This goes further than Cuadrilla’s most recent statement to DrillOrDrop which said:
“we are now analysing that data as well as drawing on expert advice to determine how we can further optimise our hydraulic fracturing programme within the very rigorous operating boundaries of the micro-seismic traffic light system”.
Mr Arnall added:
“On completion of the fracturing phase a flowtest programme will take place to evaluate well 1 before embarking on the well 2 programme.”
Greater flowback could increase costs for Cuadrilla by requiring the treatment, transport or recycling of larger volumes.
The company had estimated that 22,000 cubic metres of flowback would return to the surface for one well at Preston New Road.
A hearing is underway this morning at the High Court in London on whether the Environment Agency had required Cuadrilla to deal with flowback in the best way. DrillOrDrop will be reporting on this hearing later today.
“More appropriate” limit on earth tremors
Mr Arnall said Cuadrilla would also try to raise the threshold in the traffic light system. His statement continued:
“Concurrently Cuadrilla will engage with the regulators and the industry to clearly demonstrate that a more appropriate upper limit on seismic monitoring should be set to enable optimal testing without compromising on world class environmental and safety measures.”
DrillOrDrop has reported on evidence that Cuadrilla agreed to the 0.5 ML threshold six years ago.
Critics of fracking have argued that the 0.5 ML threshold was set for safety reasons. DrillOrDrop guest post.
Tony Bosworth, energy campaigner at Friends of the Earth, said:
“Cuadrilla clearly wants fracking earthquake regulations to be relaxed, but government should resist siren calls from a company that agreed to the regulations six years ago, and is now apparently having problems working within them.
“Only two months ago Cuadrilla said they wanted to frack the second well at Preston New Road within weeks, that date is now being pushed back. Investor patience must be wearing thin.”
Mr Arnall also referred to a video statement by Cuadrilla’s chief executive, Francis Egan. This does not appear to be online and a Cuadrilla spokesperson said:
“If AJ Lucas decides to put the video on their website you can obviously view it there, but we are not proactively sending out their shareholder video.”
A J Lucas owns 47.4% of Cuadrilla. Its shares fell slightly today. The statement suggested it would seek a “direct presence” in the UK.