Cuadrilla’s Preese Hall fracking well had to be plugged – again – after more issues

by Joe Sandler Clarke and Christine Ottery / Greenpeace

Fracking company Cuadrilla has had to repeatedly address problems with the UK’s only hydraulically fracked gas well years after its operations at the site were suspended after causing earthquakes in Lancashire, emails obtained under FOI reveal.

As recently as last summer, Cuadrilla had to take action to fix what engineers have described as a well integrity failure (though Cuadrilla denies this) at its Preese Hall site, in Lancashire, according to the emails revealed in response to an FOI request from Energydesk.

In the emails, Cuadrilla appears to agree to put an additional cement plug on the well, despite the well having already been sealed up after its abandonment in 2013.

A Cuadrilla spokesperson stressed that the well was securely plugged in November 2014, there was no leak of gas or any fluid from the well, and the integrity of the well was always secure since 2011.

The news comes amid reports that the government is attempting to fast-track fracking by relaxing some regulations – which DECC has rebutted in a new statement – though new rules around ground water testing mean fracking in the UK won’t be allowed to begin until July 2016 at the earliest.

Meanwhile, a council decision is due on whether to allow Cuadrilla to frack in Lancashire, again.

In 2011, the casing of a well drilled at the Preese Hall site was damaged by an earthquake in the area near Blackpool caused by Cuadrilla’s own drilling – forcing the firm to suspend its operations at the site.

Structural damage at Preese Hall site

Well integrity failures can result in gas or fracking fluids leaking into the surrounding environment or into the well. In the case of Preese Hall, there was a gas leak inside the well but no evidence of a leak outside the well, according to previous disclosures. 

Cuadrilla was criticised by erstwhile energy minister Charles Hendry over its failure to “recognise the significance” of structural damage to its Preese Hall well in 2011, and failing to report to government officials for six months afterwards.

Since the firm had to stop operations at the site, there have been several issues. Firstly, the well casing was deformed in the earthquakes.

Secondly, “annular pressure” was detected, which means a buildup of pressure between the borehole casing and the well.

The Health and Safety Executive (HSE) – the public body tasked with monitoring the safety of fracking sites – said the annular pressure was not or a high enough level to warrant reporting to the agency.

Pressure buildup

But in June last year, the HSE reported in an email that Cuadrilla had proposed extra remedial action to address the annulus pressure:

“Cuadrilla proposed that a section of the 5 ½” production casing will be section milled at the 9 5/8” casing shoe to enable a rock to rock cement bond. An additional cement plug will be placed above this to comply with the Oil and Gas UK guidelines on well abandonment.”

Prior to this, in order to seal the well when it was abandoned in December 2012, “cement was inserted into the production casing and a steel bridge plug inserted above the cement”.

Anthony Ingraffea, an engineering professor at Cornell University, said: “[It’s] Certainly not completely clear from these emails, but it now appears to me that remediation efforts on Preese Hall and Annas Road sites failed, and that both wells are being plugged and abandoned.”

“It is not unusual to have flow from an intermediate formation (Kinder Scout in this case) cause cementing problems and annular flows, nor is it unusual for normal plugging activities to fail to stop such flows,” he added.

Engineering expert and vocal anti-fracking campaigner, Mike Hill, said that once you have annular pressure “you do not know – and cannot be sure of [whether] the well has leaked or not.” The HSE say there has been no such leak.

Hill said he was concerned that the annular pressure was only discovered in March 2014, three years after the well was damaged in 2011.
“In line with our planning permission the Preese Hall well was securely plugged in November 2014 without incident. The well has been plugged with cement in accordance with a well abandonment plan agreed with the Health & Safety Executive. The site was fully restored in April 2015,” a Cuadrilla spokesperson said.

“Cuadrilla confirms that there has been no leak of gas or any other fluid from the Preese Hall well in Lancashire. Cuadrilla can also confirm there has been no loss of well integrity. The well integrity is secure and always has been since the well was drilled and hydraulically fractured in 2011.”

The HSE confirmed that Cuadrilla “agreed remedial action with HSE and this was implemented as part of the activity to seal and abandon the well” – and “continued to monitor the situation from a health and safety perspective throughout the decommissioning process”.

The well was abandoned in such a way that there “can be no unplanned release of fluids from it, so far as is reasonably practicable, in accordance with industry standards”, the agency added.

Correspondence between the HSE and the Department of Energy and Climate Change (DECC) last summer shows the Preese Hall situation caused the most senior civil servant working on fracking at DECC to get personally intervene – according to the most recent batch of emails on the subject.

Pressure issues set alarm bells ringing at DECC

Duarte Figueira, head of the office of unconventional gas and oil at Decc, wrote to colleagues at DECC on 15th July 2014:

“…we could have a meeting to a) fully understand the causes and potential remedies (including what the industry may do) of the annular pressure issues in both cases and b) consider handling and anything else going forward.”

He also proposed a technical presentation on the issue of annular pressure from the HSE.

The email exchange, as well as shedding light on Cuadrilla’s troubles with the Preese Hall well, also give an insight into the levels of frustration in the government about dealing with a stream of FOI requests from the public about fracking.

Figueira seemed keen to have the meeting “once the present FoI and correspondence on Balcombe and Preese Hall respectively are out of the way”.

Lancashire councillors are shortly due to decide whether to allow Cuadrilla to frack in the county again, after Lancashire County Council recommended the Little Plumpton site be approved and Roseacre Wood be refused.

Plugging and abandonment of the borehole (well) and restoration of the Fracking site at Preese Hall, Fylde

Read in full: here.

Planning permission for the variation of condition 2 of planning permission 05/09/0572 to extend the period of time for the restoration of the site to 31 December 2013 was granted on 23rd January 2013 (ref 05/11/0431). Condition 1 to permission 5/11/0431 requires that no works other than those associated with the plugging and abandonment of the borehole (well) and for the restoration of the site shall be carried out on the site and the site shall be restored in accordance with condition 14 of the permission by not later than 31 December 2013. 

Since permission 05/11/0431 was granted, the well has been partially plugged and is being monitored whilst the applicant, considers the further works necessary for its final abandonment.

The proposed time extension would mean that the visual impacts of the site would exist for longer than was previously considered acceptable. However, the proposal to extend the time limits for site restoration until the end of July 2014 is considered to be acceptable given that dry weather is necessary in which to undertake the restoration works including soil spreading. The site is well screened by the adjacent woodland, is remote from any residential properties and has a relatively low visual impact now that the drilling rig and other infrastructure have been removed from the site. The visual impacts arising from the proposed extension of time are therefore considered acceptable. The development is therefore considered acceptable in terms of paragraph 33 of the National Planning Policy Framework Technical Guidance and Policy SP2 of the Fylde Borough Local Plan.

An objection has been received from FoE on behalf of two local action groups raising a number of issues including; the risks of contamination and pollution of ground and surface waters from the escape of fracking fluids and shale gas from the fracked rock and as a consequence of the deformity to the well following the seismic events, the potential for fracking fluids left in the rock to induce further fractures and earth tremors and the quality and duration of the proposed monitoring measures. FoE consider that Environmental Impact Assessment is required in order to allow an understanding of the site conditions and the steps that are required to minimise further pollution and to secure the restoration of the site to a high standard.

The well has already been partially filled with concrete from its base to a depth of around 2000m. This includes the section of the borehole that was perforated as part of the fracking operations and the section that deformed following the subsequent seismic activity. The concreting is designed to prevent, on a permanent basis, the transfer of any gas from the shale via the borehole and would also prevent the migration of any fracking fluids from the well to both the surrounding rock and the surface. Preventing the escape of fracking fluids and fugitive gas emissions is designed to avoid the contamination and pollution of ground and surface waters.

The ground water is currently monitored via four boreholes located at the site. Three of the boreholes would be plugged and abandoned. A single borehole would be left to monitor the groundwater quality and gas concentrations for up to 12 months after the plugging and abandonment of the gas well. The monitoring frequency is and would continue to be conducted on a quarterly basis. Each quarterly visit would incorporate methane emissions monitoring of the atmosphere above the plugged and abandoned well. The applicant has advised that the well abandonment and monitoring would be undertaken in accordance with the regulatory requirements of the HSE and DECC.

The concerns raised by FoE are understood but the plugging and abandonment of the well including the monitoring of the ground water quality and gas concentrations are matters for the Health and Safety Executive, the Department for Energy and Climate Change and the Environment Agency and their respective regulatory regimes. In particular, the plugging and abandonment of the borehole is regulated by the Health and Safety Executive under the Offshore Installations and Wells (Design and Construction etc) Regulations 1996. These Regulations contain provisions relating to well integrity and abandonment as well as the selection of materials. The Regulations apply to all wells drilled under landward licences, the key objectives of which are to prevent the escape of fluids from the well which might result in pollution of freshwater or ground contamination. Under the Regulations, well abandonment techniques must prevent the transfer of fluids created by pressure gradients between different zones. Such transfer is achieved by means of the original borehole casing and the cementing and plugging operations that are undertaken as part of well abandonment.

FT.com - Cuadrilla shakes up team ahead of drilling

FT.com - Cuadrilla shakes up team ahead of drilling By Michael Kavanagh

Cuadrilla Resources, the first company to start exploratory fracking for shale gas in the UK, has replaced its chief executive as it prepares to resume drilling in Lancashire.

Francis Egan, a leading executive at BHP Billiton’s oil and gas division, takes over control of Cuadrilla next month. He will replace Mark Miller, Cuadrilla’s current chief executive, who is to stay as director of the company’s Bowland shale programme between Blackpool and Preston.

The announcement comes a day after Cuadrilla said it would be tightening its policy on conducting underground explosions as it seeks to validate estimates of large gas reserves in the shale deposit and avoid widespread public opposition to fracking.

Cuadrilla was given the go-ahead to resume fracking in the area in April even though the technique was blamed for two earthquakes near Blackpool last year. It voluntarily suspended fracking last June.

A report commissioned for the Department of Energy and Climate Change recommended the company adopt more cautious operating procedures and more robust seismic monitoring to help prevent further tremors. A final decision from DECC to approve a resumption in fracking is expected soon following a 60-day consultation period.

Surveying for shale gas has continued and last month the company issued an apology to residents who had been “surprised by the brief thuds” resulting from detonations.

Mr Miller said on Thursday that the policy on detonations would face further restrictions. After consultations with residents and Mark Menzies, the local MP, Mr Miller confirmed that the minimum distance between detonations and homes would be increased from 250m to 500m where possible in the built-up areas of Lytham, Wrea Green, Kirkham and Wesham. Detonations have been restricted to between 9am and 6.30pm.

Mr Miller’s decision to remain with the company after leading it “through a critical period” was welcomed by Lord Browne, chairman of Cuadrilla. Lord Browne, a partner at US private equity group Riverstone, which is a major investor in Cuadrilla, added that Mr Egan’s hiring would strengthen the company’s management team leaving it “well positioned to unlock the potential of shale gas and set the very highest standards of safety”. Mr Egan said: “My first priority will be to ensure Cuadrilla continues to listen to and work with our local communities in Lancashire.”

Cuadrilla fracking caused 50 tremors in Blackpool area

From the company that stated it couldn't control the fracking process, comes this latest set of claims:

Fifty separate earth tremors have been caused in the Blackpool area by "fracking", the drilling method used to extract shale gas, The Independent has learnt.

The huge number of seismic movements was admitted yesterday by one of the authors of a report into two very noticeable earth tremors likely to have been caused by the fracking operations of Cuadrilla Resources, which says it has discovered enormous supplies of shale gas in the Blackpool area.

The report, which the energy firm commissioned, concluded it is "highly probable" that Cuadrilla's operations were responsible for two tremors which hit Lancashire. The first, of magnitude 2.3 on the Richter scale, hit the Fylde Coast on 1 April followed by a second of magnitude 1.4 on 27 May. The report, which is being sent to the Government, has intensified the controversy around "fracking", or hydraulic fracturing, which involves pumping water, sand and chemicals at high pressure into shale rock, to release the gas it holds.

The company sought to play down the impact of its activities, saying that it had probably triggered "a number of minor seismic events". But when The Independent interviewed Stefan Baisch, one of the report's authors, he admitted that the actual number was 50.

In the same interview, Mark Miller, Cuadrilla's chief executive, accepted that 50 sounded like a lot of tremors but dismissed their significance. "There's a certain level of seismic activity that can occur even with a truck going past a house," Mr Miller said.

"But just because it doesn't do any damage, doesn't mean we're not concerned about it. It's not good for us if the public is concerned and it's not good for the production of gas."

Mr Miller said the report's findings were not sufficient to stop the company from using the controversial method. "Cuadrilla is working with the local and national authorities to implement the report's recommendations so we may resume our operations," he said.

Cuadrilla stopped fracking at its site in Weeton and commissioned yesterday's report into whether the practice causes seismic activity on 31 May, after concerns were raised about the tremors.

David Loveday, a shale gas expert at the Inenco energy consultancy, said the report demonstrated a "pressing need to understand the mechanism which potentially caused these earth tremors to prevent a re-occurrence".

A spokesman for the Department of Energy and Climate Change (DECC) said: "The implications of this report will be reviewed very carefully before any decision on the resumption of these hydraulic fracture operations is made."

The findings coincided with a day of environmental opposition to the practice, as protesters from the Frack Off campaign group occupied another Cuadrilla site near Southport, shutting it for the day. Frack Off also staged a rally in London.

The Cuadrilla findings are likely to feature in the Commons today, when the Energy minister, Charles Hendry, appears before the Energy and Climate Change Select Committee.

Before the publication of yesterday's report, which was conducted by a team of independent experts, Cuadrilla had stressed that there "was no proven link between the seismic events and the hydraulic fracturing". Yesterday, it conceded that 50 such events had occurred in eight months.

The company said: "The seismic events were due to an unusual combination of geology at the well site coupled with the pressure exerted by water inject. This combination of factors was extremely rare and would be unlikely to occur together again."

The report stressed that while a "worst-case scenario" could result in a magnitude 3 earthquake in the Blackpool area, this "would be unlikely to occur" and, if it did, "there is no threat to people or property". Cuadrilla claimed that an earthquake of 2.6 on the Richter scale would be "the maximum level allowed".

Dr Brian Baptie, a seismologist at the British Geological Survey, which is advising DECC on whether to allow the resumption of fracking in the UK, said: "Fifty seismic events does seem a lot, but most were very, very small."

He added that a magnitude 2.6 earthquake, at this depth, would not cause any structural damage but "might cause strong shaking that would be widely felt by people indoors and out".

Cuadrilla is at the forefront of shale gas exploration in the UK and raised strong hopes for the future of the industry in September when it revealed that its field in Lancashire contained up to 5,660 billion cubic metres. About a fifth is expected to be recoverable.

Mr Miller said: "We unequivocally accept the findings of this independent report and are pleased the report concludes that there is no threat to people or property in the local area."

Cuadrilla's estimate for shale gas in Lancashire's Bowland basin cannot be trusted

Posted by Tim Probert

The British Geological Survey (BGS) is working on a new estimate of the amount of shale gas in Lancashire’s Bowland Basin after suggesting Cuadrilla Resources’ figure of 200 trillion cubic feet (tcf) – enough to meet national natural gas demand for 56 years – could be flawed.

Head of energy Mike Stephenson said it is impossible for the BGS to verify the accuracy of Cuadrilla’s estimate for ‘gas in place’ in a 500 square mile area of Northwest England, as the Lichfield-based shale gas developer has not yet submitted its methodology for calculations. Concerned Cuadrilla’s estimate is inaccurate, the BGS is now conducting its own survey, which it hopes will give a clearer indication of how much shale gas is recoverable.

“As far as I’m aware, Cuadrilla has not given a clear methodology for the basis of their calculations,” says Stephenson. “We are working on a new figure with a volumetric basis for the calculations, so we will come up with a much more accurate figure shortly”. The BGS’ official estimate of the potential resource of the Bowland shale is 4.7 tcf, significantly less than this September’s announcement by Cuadrilla, the only company in the UK to have drilled for shale gas to date.

Speaking at this week’s Shale Gas Environmental Summit in London, Stephenson stated: “We worked out our old resource figure for the Bowland shale, somewhat crudely, by comparing the recovery rate for Barnett shale in Texas, which is the same geological age, and multiplying it by the land area of Bowland. Cuadrilla’s estimate of 200 tcf is about 40 times higher.

“I’m not knocking Cuadrilla’s estimate because they have gas yield data from their two wells whereas we have none, because no-one has drilled shale gas wells in the UK,” he added.

Earthquakes no headache?
Cuadrilla halted shale gas drilling operations in May after two small earthquakes near Blackpool. The Department of Energy and Climate Change (DECC) was tight-lipped over when it would make a decision on whether to allow Cuadrilla to resume exploration in the Bowland basin near Blackpool. “We will take our time,” a DECC spokesman told Millicent Media.

Commenting on Cuadrilla’s report submitted to DECC on 2 November, which concluded a link between hydraulic fracturing, or ‘fracking’, and the earthquakes was “highly probable”, Stephenson said the BGS was not unduly concerned by the shale gas developer’s assertion that “the theoretical maximum seismic event of magnitude 3 would not present a risk to personal safety or damage to property on the surface”.

“Earthquakes of magnitude 3 may cause things to fall off shelves, but in our experience they can’t be felt by human beings,” he said. “They are probably too small to cause damage.”

Stephenson said the lack of peer-reviewed research into shale gas fracking, particularly the potential contamination of water supplies, was of great concern to the British authorities. Only two peer-reviewed reports have been conducted into methane leakage and their conclusions are viewed as highly questionable by most geologists, he said.

The BGS and the Environment Agency now intend to conduct a baseline study into the impact of fracking and potential methane contamination of groundwater. “We want to determine the background levels of methane in groundwater before anybody fracks so that any other methane found can be attributed to fracking,” explained Stephenson.

“It’s very important to do a baseline study. It can be done quickly, it’s just a case of measuring wells and the amount of methane in them. It’s a priority, but it doesn’t need to stop the fracking process.”

Fracking caused earthquakes, researchers find

The deep underground drilling was found to be responsible for minor tremors on the Fylde coast.

http://www.guardian.co.uk/environment/the-northerner/2011/oct/17/earthquakes-fracking-fylde-coast

Gas drilling deep beneath the Fylde coast did cause minor earthquakes, a report confirmed on Monday.

The shale gas company Cuadrilla Resources – has been urged to stop causing the tremors or face the prospect of having its operations closed down.

The company had been in discussion with the Department of Energy and Climate Change to consider a report into the risk of earthquakes associated with fracking - the process used to extract shale gas from deep beneath the Fylde coast.

The meetings followed the British Geological Survey's conclusion that two recent earth tremors felt were most likely to have been caused by fracking.

The British Geological Survey said the correlations between the earthquakes and the time of fracking operations and the proximity of the quakes to the site, all pointed towards the earthquakes being a result of the process.

Seismologist Brian Baptie said: "These were still very small earthquakes, even by UK standards and won't cause any damage. If fracking continued I couldn't see the tremors getting much bigger."

He added that it's obviously a concern for residents.

Cuadrilla has been criticised for its drilling technique, which involves pumping high volumes of water and sand into drill holes to crack the rocks so gas can be extracted. The company commissioned a report following the tremors earlier this year.

Shortly after the quakes were felt the firm halted its operations after admitting the low magnitude tremors felt in Poulton in April and May, close to Cuadrilla's Singleton site could be connected.

And geoscientists said Cuadrilla's operations could be shut down permanently if proposed methods to reduce the risk of earthquakes fail.

Toni Harvey, a senior geoscientist at the Department of Energy and Climate Change said: "If we allow fracking to continue and their mitigation didn't work, then we would shut them down again, without a doubt. There is a lot of concern in the media and from ministers about public safety.

"DECC has requested a detailed report from Cuadrilla, which we understand they are close to finalising. When the report is received, it will be carefully considered, with input from British Geological Survey and other experts."

Last month Cuadrilla, the first company to explore for shale gas in the UK, announced the Fylde coast holds a total potential resource of 200 trillion cubic feet of gas. It estimated the discovery - between Blackpool and Southport - could be worth £6bn to the UK economy and create 1,700 jobs locally.

However protesters are campaigning to stop the drilling and the delightfully named anti-group, Frack Off, rallied outside the DECC headquarters as the company presented the study.

Philip Mitchell, chairman of Blackpool and Fylde Green Party, called on the government to halt all UK hydraulic fracturing industry activity until there had been a thorough evaluation of the risks.

He said: "Any suggestion of an acceptable level of earthquakes caused by fracking should be rejected.

"The government must realise it must stop treating our communities like guinea pigs and accept these techniques carry unacceptable risks to the British public.

"Ministers must stop the industry activity at least until parliament and the public can be guided by a full and robust appraisal of the total risk to the themselves and to the environment."

Mark Miller, the CEO of Cuadrilla Resources, said they had a useful, in-depth working session with officials on the initial findings of the report.

"There is some considerable work still to do and we absolutely share with DECC the need to have the complex issues involved addressed dealt with satisfactorily," he said.

Aiden Attewill, from Frack Off, likened the process as scraping the bottom of the fossil fuel barrel. "We need to stop putting off these problems and really address issues of resource depletion and climate change," he said.

FT.com: Earthquake fears halt shale gas fracking

FT.com, 1st June 2011, World > UK > Business, By Sylvia Pfeifer and Elizabeth Rigby.
Read article in full here: http://www.ft.com/cms/s/0/0577dda0-8c82-11e0-883f-00144feab49a.html#ixzz1OlOkUPyK

“We have discussed with Cuadrilla and agreed that a pause in operations is appropriate so that a better understanding can be gain ed for the cause of the seismic events,” said the Department of Energy and Climate Change. It added that the department needed the re sults of a study being carried out by the British Geological Survey and Keele university before deciding on the next steps.

Brian Baptie, a seismologist at the BGS, said that following a magnitude 2.3 earthquake on April 1 the organisation had installed monitoring instruments close to the site.

A subsequent earthquake was recorded in the early hours of May 27, at a depth of about 2km and with a magnitude of 1.5. The analysis showed that the epi centre was within 500m of the well site, said Mr Baptie.

“The timing of these earthquakes and that of the fluid injection [during fracking] indicates that there might be some connection between the two,” he said, adding that there was no historical record of a lot of seismic activity around Blackpool.

Fylde MP Mark Menzies welcomes Fylde fracking halt and publishes Cuadrilla PR release

8th June 2011: Fylde MP Mark Menzies republishes Cuadrilla PR release:
http://www.markmenzies.org.uk/news/shale-gas-drilling-an-update

Shale gas drilling update
June 8th, 2011 admin

MARK Menzies MP has welcomed the decision by Cuadrilla Resources to voluntarily postpone their hydraulic fracturing operations at Preese Hall whilst an investigation into seismic activity is carried out.

Here is the latest statement from the company:

Cuadrilla Resources has voluntarily decided to postpone its hydraulic fracturing operations at Preese Hall 1 following small tremors located close to the site on 1 April and 27 May 2011. This decision has the agreement of the Department of Energy and Climate Change (DECC).

Cuadrilla is producing a detailed geo-mechanical report for DECC in association with The British Geological Survey and Keele University – both are recognised experts on the subject.

The report will focus on whether there are links between the seismic events and the hydraulic fracturing process and what can be done to mitigate against any risks should a connection be proven. This report will take up to eight weeks to produce – possibly longer – depending upon the availability of qualified technical experts to undertake the work involved.

At present no proven link between the seismic events and the hydraulic fracturing has been established but Cuadrilla Resources consider the decision to postpone as being a prudent and responsible response. Hydraulic fracturing will not recommence until discussions are satisfactorily concluded with the regulatory authorities.

The intensity of the tremors is well below anything that could be realistically considered as an earthquake with any meaningful or tangible local impact. The tremors have not led to any recorded structural damage or physical injury and the British Geological Survey describes these tremors in a statement as “pretty insignificant even by UK standards”.

Contrary to some misreporting in the media, drilling operations are not affected as no link has been suggested between drilling and seismic activity. Therefore the Grange Hill site is still active. Plans to drill at a site near Becconsall, between Preston and Southport are progressing and public consultation is already underway with the local community and officials. A community consultation event attended by over 100 local people took place on 6 June.

Cuadrilla is investing in more seismic monitoring equipment for the operations to enhance the coverage already supplied by the British Geological Survey which was installed after the 1 April event at Cuadrilla’s request.

Cuadrilla remains certain that its operations are completely safe for people, property and the environment