Cuadrilla wants to use more chemicals to improve fracking at shale gas site

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Tankers leaving Cuadrilla’s shale gas site, 2 January 2019. Photo: Ros Wills

The shale gas company, Cuadrilla, is seeking permission to add new chemicals to its fracking operations in Lancashire.

In details published today, the company said it wanted to change the composition of the fracking fluid so that more sand could be carried into fractures in the shale rock.

This follows news earlier this month that Cuadrilla had fully fracked only 5% of its first well at the site at Preston New Road near Blackpool. Fracking operations, between October and December 2018, were paused at least five times because they induced earth tremors measuring 0.5ML or above. Fracturing equipment has since been moved off the site.

Today’s  application to the Environment Agency also seeks permission to use methanol, an “optimised fracking fluid” and a new biocide. If approved, the changes would additionally make it clear that Cuadrilla can frack each well more than once.

Local opponents of Cuadrilla’s operation described it as a “desperate attempt to revive a dying industry” and said it felt as if they were being “fracked by trial and error”.

This is the latest in a series of changes to the environmental permit for Preston New Road. Cuadrilla submitted its first application nearly five years ago in June 2014. These latest proposals, if approved, would become version nine.

The changes incorporate “operational refinements identified during site operations to date”, Cuadrilla said, and “more precisely reflects the site’s procedures and operational controls”.

A public consultation began today and continues until 20 March 2019.

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Cuadrilla’s Preston New Road shale gas site, 25 December 2018. Photo: Ros Wills

Proposed changes

Frack fluid

Cuadrilla said it was seeking approval for the use of what it called “an optimised hydraulic fracturing fluid” to allow for “operational flexibility during hydraulic fracturing”.

The company’s environmental manager, Nick Mace, said:

“we’d like to modify our fracturing fluid so that more sand can be carried into the shale rock with the water when we recommence hydraulic fracturing operations at the Preston New Road site. To do this we proposed to add some chemicals which have already been approved for use elsewhere in the UK by the Environment Agency.”

During hydraulic fracturing last year, Cuadrilla complained that it had been unable to pump sand far enough into the shale rock without causing earth tremors.

The waste management plan, which accompanied today’s application, said the company wanted to use a more viscous fracking fluid than had been tried so far.

Higher viscosity fluid can transport sand at lower rates. It also helps to initiate fractures and increases the fracture width to allow more space for the sand, the waste management plan said.

The application proposes increasing the concentration of friction reducer in the fracturing fluid from 0.05% to 1%. It also considers the use of gelling agents, at about 4% by volume, to transport the sand along the lengths of the fractures.

So far, Cuadrilla has said it added only the friction reducer, polyacrymalide, and sand to the water to frack at Preston New Road.

The new application lists about 40 hydraulic fracturing fluid additives, described variously as cross linkers, gelling agents, carriers, pH buffer/activator, cleanup/flowback aid, clay control/brine, carrier, gel breaker, delay agent and scale control.

The company said the additional ingredients would remain non-hazardous to groundwater. They were commonly found in food, toiletries and other products used around the home, it said.

Other chemicals

Hydrochloric acid Cuadrilla said this would help reduce fracturing pressure. It would dissolve drilling mud remaining in the wellbore and “facilitate entry of the fracturing fluid from openings in the production tubing to the body of shale”. The company said the acid would be used on the well before fracking. An estimated 3-15m3 per fracture stage would be needed. It would be stored at a strength no greater than 10%, the company said.

Methanol Cuadrilla said this would be used to prevent the formation of gas hydrates during well suspension. An interim decision by regulators has considered methanol non-hazardous to groundwater, Cuadrilla said.

Glutaraldehyde Described as a non-hazardous biocide, Cuadrilla said this was an alternative way of treating bacteria to ultraviolent light

Multiple fracks

Cuadrilla said the new permit would clarify that each horizontal well could be re-entered and hydraulic fracturing may be conducted on more than one occasion. Each re-entry would be individually planned and managed, the company said.

Well workovers

The documents stated that periodic well workovers or other well interventions would potentially be needed at Preston New Road and would be covered by the revised permit.

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Gas flares at Cuadrilla’s fracking site at Preston New Road near Blackpool, 2 November 2018. Photo: Cuadrilla Resources

Flaring and nitrogen lift

The waste management plan said propane could be added to help burn gas produced from the initial well test. DrillOrDrop asked Cuadrilla a series of questions about flaring and whether shale gas was being vented at Preston New Road.

The spokesperson for the company said:

“We consider that there is more than sufficient information provided about our application to vary the current permit at Preston New Road. We respect this process and Cuadrilla has nothing further to add at this stage.”


Cuadrilla seeks to reduce the frequency of surface water monitoring to monthly, which was, it said, “more proportionate to risks presented by the site”.

On air quality monitoring, the company is seeking to stop collecting data on a range of pollutants at off-site stations. The substances include methane, carbon monoxide, nitrogen dioxide, nitric oxide, sulphur dioxide, ozone, total petroleum hydrocarbons, VOCs, particulates (PM10 and PM2.5) and dust. Cuadrilla said collection of this data had been superseded by onsite continuous monitoring.


A spokesperson from Preston New Road Action Group said:

“It feels as though we are being fracked by trial and error: this seems like another desperate attempt to resurrect this dying industry.

“How will changing the fracking fluids prevent seismic events? Just more worry for the unfortunate guinea pigs living close to the site.”

Frack Free Lancashire said

“We are concerned (but not entirely surprised) that after years of claiming that the only two chemicals to be used in UK fracking were polyacrylamide and hydrochloric acid, that they should now be seeking, after just one failed frack, to expand the list of chemicals available in their inventory to add to their fracturing fluid.”

The group added:

“Equally concerning is the list in the application documents of 41 potential additives to their drilling fluids of which no less than 14 are described by Cuadrilla themselves as “potentially hazardous”.

“We predicted that the list of chemicals would inevitably be expanded as this project continued and will continue to monitor the situation.”

More questions

DrillOrDrop also asked Cuadrilla for clarification on a range of issues arising in the revised waste management plan. This included questions about drilling muds, the use of methanol and hydrochloric acid, re-fracturing of the wells, fracturing plans for wells 3 and 4, and waste sand. The company was not willing to answer our questions.

Updated 21/2/2019 to increase the number of hydraulic fracturing fluids additives listed in the application

50 replies »

  1. Surely Frack Free Lancashire know Cuadrilla have had more the one failed frack (Preese Hall), I mean the rest of the country does, so why not their spokesperson!

        • Refracktion – that’s not a nice thing to write. Surely you know that Joe is academically very gifted and got a 2:2 in his degree and passed a Masters in a social science subject. He’s been shamefully mistreated by the system and apparently is out of work due to being on a blacklist for his political beliefs not least for telling the world that all our radioactive waste will be put into wellbores at PNR as soon as Cuadrilla leave. I think you should show a bit more support for JC’s righthand man and a future leader of the left.

  2. Tina Louise Rothery has posted on Facebook saying the chemical is poisonous. She doesn’t bother to mention that it can be bought on Amazon and is currently used in Hospitals and Dental practices to sterilize instruments. Your GP can also prescribe it as a medication. #Another Own Goal

  3. I would suggest they try sun screen. I find it is often able to take sand into cracks and crevices in an almost mystical manner.

    • Rowland and Marie – maybe you could provide an example of anywhere in the world where fracking has caused subsidence – I won’t hold my breath

      • Aren’t the Taylors really talking about the tremors induced by fracking?

        If you’d read the OGA report into the Horse Hill/ Newdigate earthquake swarm you’d have learnt of just the sort of subsidence caused by tremors that the Taylors are concerned about, this example damaged the grounds rather than the house which cost the owners a lot more as it turns out.

        That day there were 2.6, 1.8 and 1.7 ML tremors, the last at 12.11 PM. To quote the OGA workshop “….a landslide at noon on 1 April some 10km from the epicentres. This occurred in Weald Clay adjacent to a fault shown on the BGS Geological map. The landslide was some 50 metres in length with a vertical displacement of some 10 metres. It removed half the gardens of three adjacent properties. The toe of the slide disturbed the roots of many trees causing them to tilt towards the slide and having to be removed. Remedial work to stabilise what is left of the 3 gardens is estimated at £600,000. The householders will pay the damage themselves (Normal house insurance does not extend to the grounds of a house).”

        Of course you will say these tremors weren’t caused by UKOG at Horse Hill drilling through the fault 3kms from the tremors, and many small investors will believe you.

  4. What do you believe tests are for, R&M??

    Heaven knows how you manage within the NHS. My eldest son is in hospital currently, subject to a lot of testing, so that his outcome can be optimised.

    That is intended to produce winners, not losers.

    • Rowland an Marie, It’s nice that you live by the coast although I struggle to see what relevance that has to this discussion. Maybe you could point me to the evidence that houses were damaged as a result of fracking – I’ve certainly not seen it and there have been no compensation pay outs to suggest that such damage occurred. Indeed, damage resulting from such a small tremor at such a depth would be very interesting for scientists so I’m surprised that I’ve not been reading articles on said damage in academic journals.

      I’m also very impressed by the knowledge of local people being able to predict the presence of a fault in a well drilled at 2.5 kms depth. Could they tell me which team is going to win the football league while they’re at it?

      • Judith. I think you’ll find Rowland and Marie, who are residents ofthe Fylde coast, are referring to Cuadrilla’s previous attempts at fracking at Preese Hall. Homes were damaged. The fact that you haven’t seen them is irrelevant. The well was certainly damaged and it’s what goes on underground that is the worry. As far as being warned about faults. Cuadrilla were warned and chose to ignore it.

  5. People need to be aware of major research published last year that flags up environmental implications about Glutaraldehyde in fracking in the USA.

    According to the team of eleven researchers, “This study shows that there are long lasting effects in streams impacted by Hydraulic Fracturing, which need to be considered for environmental impact assessment and bioremediation strategies.”
    “Abiotic factors such as acidified pH may affect the microbial community’s ability to respond to a second or continuous exposure to Hydraulic Fracturing waste, causing Hydraulic Fracturing chemicals to be more persistent in the environment than expected.”
    “As Hydraulic Fracturing practices keep expanding worldwide, this knowledge can help bioremediation efforts to optimize natural attenuation and aid Hydraulic Fracturing companies to make better decisions about amendments to use in Hydraulic Fracturing fluids.”

    The precautionary principle shows it would be unwise to grant permission for Cuadrilla to use Glutaraldehyde until further research has been done in the USA that clarifies the scale and nature of the impacts of Glutaraldehyde on USA ponds, ditches, streams and wildlife. Once that has been done, only then should Glutaraldehyde be considered for Lancashire, if at all.

    Even then it would require an Environmental Impact Assessment. Until then, Lancashire County Council, as the Minerals Planning Authority should refuse planning permission for Glutaraldehyde to be used.

    Anyone can download the research article here free of charge as a pdf:
    [Impacts of Glutaraldehyde on Microbial Community Structure and Degradation Potential in Streams Impacted by Hydraulic Fracturing. Authors: Maria Campa, Stephen Techtmann, Caleb Gibson, Xiaojuan Zhu, Megan Patterson, Amanda Amaral, Nikea Ulrich, Shawn Campagna, Christopher Grant, Regina Lamendella and Terry Hazen (April 23, 2018). Environmental Science & Technology, volume 52, pages 5989-5999]

    Jackie Matty Neil Stewart mentions that Glutraldehyde “can be bought on Amazon and is currently used in Hospitals and Dental practices to sterilize instruments. Your GP can also prescribe it as a medication.” Correct, but misleading. We are discussing somewhat deeper drilling, and large volumes being used capable of having “long lasting effects in streams impacted by Hydraulic Fracturing, which need to be considered for environmental impact assessment and bioremediation strategies.”

    Robin Grayson MSc Liberal Democrat Geologist

    • Robin, People should really be aware about the study which showed that you die if you hold your head in water for 10 minutes.

      The environmental impacts of using Glutaraldehyde in the UK are totally insignificant – there is no way that it will be released into the environment.

      If you’re so keen on the precautionary principle maybe you should try applying it to mining of REE, lithium or the manufacture of carbon composites for windmills etc. You seem totally obsessed with the dangers of hydraulic fracture stimulation yet you don’t seem to put those risks in context with other forms of energy production.

      The argument about the impacts of glutraldehyde on microbial communities is ridiculous and was probably made by microbiologists trying to get research funding by raising a problem that doesn’t exist. The fracking fluids that contain glutraldehyde will be pumped into shale. The shale will have a pore diameter of something line 5 to 50 nm, which is far smaller than the size of the microbes. So in the laboratory some desperate scientists might have found some issue in terms of the impact of glutraldehyde on microbial communities but in the real world it isn’t an issue.

      • Simon Maynard,

        Thanks for your reply but you need to do a bit more homework.

        For instance, indeed yes the Bowland Shale has extremely tiny pore diameters, but that is before fracking cracks the shale. Then the cracks are wide enough for the fracking fluids to enter, carrying with them the proppant to keep the cracks wide open. The proppant consists of quartz sand grains NOT microscopic, but classed as fine sand, such as from Chelford Sand Quarry near Jodrell Bank. Please understand that the glutaraldehyde enters anywhere in the cracks in the shale kept open by the proppant sand grains.

        You are courageous in challenging USA scientists regarding their concerns about glutaraldehyde and I suggest you download their research paper and then contact the authors if you are still unhappy about their work.

        But before you contact them, please be aware that their research demonstrates than glutaraldehyde leaking from fracking wells affects microbial communities in surface waters, and that is their concern.

        You mention “there is no way that it will be released into the environment.”
        Sorry to disappoint, but the USA evidence is clear: glutaraldehyde is known to leak from USA fracking wells into the environment.

        Robin Grayson MSc – Liberal Democrat Geologist

        • Robin, if you look at microseismic data or understand the mechanics of hydro fracture generation then you would know that hydraulic fractures don’t propagate to a depth or temperature where microbial communities are present. There is no leakage from hydraulic fractures in the USA only leakage from storage pits which aren’t allowed in the USA. It seems me that you don’t like hydraulic fracturing and are trying to find any pathetic argument to justify you’re gut feeling. I’ve been told that your BSc thesis was good and your MSc was reasonable – it’s a shame that your scientific understanding went down hill from there. Never mind – it happens to a lot of people’s me.

  6. Robin, open frack water ponds are illegal in Europe. So tell me what would be the pathway for the glutaraldehyde to be ingested by humans, or animals, or get into local water courses? Also if you can think of a pathway, how does that compare with substances that are much more of an environmental or health & safety concern carried regularly along the road outside the PNR site that are nothing to do with fracking & might get ingested by humans, animals or end up in watercourses?

    • Nick, I actually hadn’t read much about this because I know that glutaraldyhyde is used in many household products and is harmless. I just presumed that it was injected, produced and then treated using very simple and well established techniques. However, I did bother to read some of the academic papers on the subject and found that in most circumstances it actually doesn’t make it back to the surface. In other words, the papers are saying that IF injected into a cold shale, and IF it doesn’t get adsorbed to or react with the shale there is a chance that some would be produced in the flow back fluid. It can then be treated in the normal inexpensive and effective manner.

      Once again we have those against fracking scraping the bottom of the barrel and twisting research results so that they align with their instincts.

      I don’t expect that you’ll get a realistic leakage mechanism from our resident polymath!

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