A report commissioned by the government has compared recent fracking-induced earth tremors in Lancashire to doors slamming and falling frying pans.
The research, published today by the University of Liverpool, likened the largest tremor recorded so far at Cuadrilla’s Preston New Road site to dropping a 1kg bag of flour on the floor from the height of a kitchen counter.
The report looked only at the equivalent vibrations that would be felt at the surface. It did not examine impacts of seismic activity on the borehole or the integrity of the well. Anti-fracking campaigners in Lancashire have described it as “pseudo-science” and “an attempt to distract the public with childish comparisons”.
Cuadrilla’s fracking operation at Preston New Road has caused 36 small tremors since pumping began on 15 October 2018. They happened on 13 days and the company has stopped operations because of seismic activity at least three times. DrillOrDrop tremor tracker
According to the report, vibrations from the largest tremor so far, (1.1ML recorded on 29 October 2018) would be the equivalent of three pans or the 1kg bag of flour dropping to the floor.
A 0.8ML tremor, which was recorded on 26 October 2018, was likened to vibrations at the surface of one person jumping.
The 0.5ML threshold at which fracking must stop under the government’s traffic light system, was compared with vibrations from mixed traffic on a busy road or slightly less than that from a door slamming.
Smaller earth tremors recorded near the site were compared with closing a window, a delivery van arriving or a washing machine on spin cycle. Seven of the examples involved dropping items to the floor but did not specify the type of floor.
The University of Liverpool said the report was commissioned by the Department of Business, Energy and Industrial Strategy (BEIS) but paid for by the university. The research was carried out by the School of Environmental Sciences. One of the authors, Ben Edwards, contributed to Cuadrilla community newsletter, distributed to Lancashire homes last month.
The report said the purpose was to:
“Provide a context to induced seismicity and the associated traffic light system (TLS) for hydraulic fracturing operations in the UK.”
It gave results from 39 scenarios, ranging from a tremor of -0.4 (bus passing on the opposite side of the road) to 2.1 (a toddler playing on a wooden floor). It acknowledged that earth tremors might be more likely to be felt in quiet areas or at night than the vibrations from the examples it gave.
The report’s findings were dismissed by the campaign group, Frack Free Lancashire. A spokesperson said:
“It is very interesting to see how these academics have passed their time, but having studied their findings, we can’t see where they look at the potential impact of seismic events on the well bore underground.
“The larger seismic events (1.5Ml and 2.3Ml) at Preese Hall in 2012 resulted in ovalisation of the well bore over a considerable distance. In that context, whether the size of the quake involved is the equivalent on the surface of a honeydew melon dropping is wholly irrelevant.
“We need a proper informed debate on these issues and not pseudo-science which ignores the relevant issues and attempts to distract the public with childish comparisons.”
In a guest post published by DrillOrDrop yesterday, engineer Michael Hill said:
“The industry is endeavouring to focus the media and public’s eyes on “felt” seismicity. It is talking about the level of earthquakes that actually shake our houses.
“But the risk at the moment is not to construction above the ground but to what lies below: the wellbore itself.
“We do not know the intensity of the ground movement at the borehole but it is immediately clear that the intensity at the wellbore must be greater than at the surface.”
When did Cuadrilla last frack?
The report is dated 6 November 2018, two days after the most recent seismic activity recorded near the site by the British Geological Survey (BGS).
This was a 0.7ML event on 4 November, which happened when fracking was not taking place and was described as a trailing event. DrillOrDrop understands that Cuadrilla had not fracked for 48 hours before that event. This was a mini frack on Friday 2 November 2018.
Since the 0.7ML event, the BGS has recorded no seismic activity in the area (BGS online data). Cuadrilla reportedly told a meeting last night of the Preston New Road community liaison group that it did not frack last week (5-10 November 2018).
DrillOrDrop asked the company to confirm this. A Cuadrilla spokesperson would not comment on the meeting until formal minutes were published. The spokesperson previously said:
“With regards to our operations at Preston New Road, we are continuing to test our exploration well in Preston New Road, Lancashire, including testing the responsiveness of the shale to fracturing. We are also analysing the recent natural gas flow at the surface and other data which is available to us following the start of our hydraulic fracturing programme last month. However, we are not giving a stage by stage update on each frac.”