http://www.dailymail.co.uk/news/article-2056630/Fracking-DID-cause-earth-tremors-Blackpool–drilling-goes-on.html#ixzz1cepGj3zz
By Oleg Vukmanovic
LONDON | Wed Nov 2, 2011 1:58pm EDT
(Reuters) – Shale gas exploration triggered small earthquakes near Blackpool in northwest England earlier this year, UK firm Cuadrilla Resources said, adding to concerns about the safety of a technology that is transforming U.S. energy markets.
A spokesman said on Wednesday tremors were triggered by pumping vast quantities of water at high pressure 3 kilometres underground through drill holes in a process known as hydraulic fracturing, or fracking, which is designed to prop open shale rocks and release trapped gas.
“It is highly probable that the hydraulic fracturing of Cuadrilla’s Preese Hall-1 well did trigger a number of minor seismic events,” a report commissioned by the company said.
Environmentalists on both sides of the Atlantic have lobbied politicians to ban fracking on concerns it leads to pollution of ground water and leakage of gas into the atmosphere.
Britain suspended fracking following the May tremor and commissioned a report into the process, but Cuadrilla has since said there was little risk that the tremors in April and May of 2.3 and 1.5 on the Richter scale, respectively, would be repeated.
Cuadrilla said the drill site’s combination of geological factors is “extremely rare” and would be unlikely to occur together at future drilling locations.
Even if tremors occurred, the magnitude of any future tremors would be no more than around 3 on the Richter scale as a “worst-case scenario”, it said.
“Cuadrilla’s water injection operations take place very far below the earth’s surface, which significantly reduces the likelihood of a seismic event of less than 3 on the Richter scale having any impact at all on the surface,” the company said in a statement.
The Lichfield-based company has said its site near Blackpool had 200 trillion cubic feet of gas in place – enough to cover UK demand for years.
However, experts questioned the size of the find, and a financing conducted by a key shareholder in Cuadrilla suggested gas reserves were below the company’s estimate.
ACTIVISTS SLAM FINDINGS
Cuadrilla has proposed implementing a seismic early warning system to make local people feel safer. But activist and environmental groups say the measure would mask the real risks of fracking in Britain.
WWF-UK has called for a moratorium on shale gas exploration until environmental risks have been properly assessed.
“These findings are worrying and are likely to add to the very real concerns that people have about fracking and shale gas,” Nick Molho, head of energy policy at WWF-UK said.
France banned shale drilling in July in the face of concerns about potential environmental damage due to the large amounts of water and detergents used in fracking.
On top of earthquake risks, the U.S. experience shows shale drilling sucks funding away from renewable energy projects while at the same time polluting air and water supplies, according to Friends of the Earth.
However, legal experts say findings presented to the UK’s Department of Energy and Climate Change signal that a suspension on fracking in the UK is not likely to last.
“In the U.S., where significant shale gas development has been underway for many years … there have been very few instances of water contamination,” said Lynne Freeman, partner at law firm Reed Smith.
“Those instances have largely resulted from surface spills or improperly cemented well casing, and the fracking process has earned a strong safety and environmental record,” she said.
PROTESTERS STORM RIG
Ahead of the fracking report’s publication, nine protesters from Frack-Off, a UK anti-fracking group, ran on to the company’s drilling site at Hesketh Bank before dawn and scaled the rig using climbing equipment, the group said.
Frack-Off says it intended to draw attention to the harmful effects of shale drilling on local environments and bring operations to a standstill “for as long as possible”.
Cuadrilla said it is working with police to remove four protesters attached to a rig.
(Additional reporting by Tom Bergin; editing by Jane Baird)
________________
excellent graphics online at:
http://www.dailymail.co.uk/news/article-2056630/Fracking-DID-cause-earth-tremors-Blackpool–drilling-goes-on.html#ixzz1cZGUkh9O
Daily Mail, UK
It’s official: Fracking DID cause earth tremors in Blackpool… but drilling goes on
* Controversial gas drilling process blamed for tremors
* Protesters scale a shale gas rig near Southport
* There is an estimated 200trillion cubic feet of natural gas under Lancashire
* This is a huge amount of fuel – enough to power Britain for 50 years
By DAILY MAIL REPORTER
Last updated at 2:56 PM on 2nd November 2011
A controversial ‘fracking’ technique to extract gas from the ground was the ‘highly probable’ cause of earth tremors which hit Lancashire’s Fylde coast earlier this year, a report concluded today.
One tremor of magnitude 2.3 on the Richter scale hit the area on April 1 followed by a second of magnitude 1.4 on May 27, prompting locals and environmental campaigners to blame the fracking technique being used locally by oil and gas firm Cuadrilla.
Fracking involves extracting gas reserves from underground by a process of hydraulic fracturing of shale rock using high pressure liquid to release gas – a process green groups claim is damaging the environment.
Protesters scale a Cuadrilla shale gas rig bringing a halt to work at the site near Southport, Merseyside. Gas drilling by the company did cause a series of earthquakes along the Lancashire coastline, a report today said Fracking involves extracting gas reserves from underground by a process of hydraulic fracturing of shale rock using high pressure liquid to release gas – a process green groups claim is damaging the environment
The firm commissioned a report by independent experts to investigate any links between the tremors and fracking work at their Preese Hall-1 well in Lancashire.
Today a summary published by the company said it is probable the fracking caused the tremors.
It said: ‘The report concludes that it is highly probable that the fracking at Preese Hall-1 well triggered the recorded seismic events.
‘This was due to an unusual combination of factors including the specific geology of the well site, coupled with the pressure exerted by water injection.
‘This combination of geological factors was rare and would be unlikely to occur together again at future well sites.
‘If these factors were to combine again in the future, local geology limits seismic events to around magnitude 3 on the Richter scale as a worst-case scenario.’
The report said a ‘number of factors coincided to cause the seismic events’.
First, the gas well encountered a ‘pre-existing critically stressed fault’ which ‘accepted large quantities of fluid’, and the fault was ‘brittle enough to fail seismically’.
The two tremors were ‘most likely’ induced by ‘repeated direct injection of fluid into the same fault zone’, the report states.
But it goes on to say the probability of a repeat occurrence of a ‘fracture-induced seismic event’ with similar magnitude is ‘very low’.
The report was published at 9am today, hours after protesters stormed the firm’s gas exploration site.
Environmental campaign group Frack Off entered the shale gas rig at Banks, near Southport, at around 5.30am.
HOW MUCH SHALE GAS IS BENEATH LANCASHIRE?
British energy consortium Cuadrilla Resources has discovered that Lancashire is sitting on one of largest reserve of ‘shale gas’ in Europe.
According to results from its test wells, there are 200trillion cubic feet of natural gas under the ground, trapped in a layer of compacted mud.
If the gas can be recovered, it could provide Britain with enough fuel to last 50 years, plug the looming energy shortfall caused by reduced North Sea gas supplies and create 5,600 jobs.
And it could turn Blackpool from the leisure capital of the North, to the centre of England’s oil and gas industry – a Texas-by-the-sea.
Two hundred trillion cubic feet is an unimaginably vast amount of gas. It is ten times more than all the gas known to be left under the North Sea. It’s one-fifth the size of the biggest gas field in the world, and the volume of 66,666 Royal Albert Halls.
The prospect of 400 gas wells across Lancashire and thousands of new jobs – not to mention all those tax revenues – couldn’t have come at a better time for the Chancellor. But there is one problem – in gas and oil exploration, if something sounds too good to be true, it usually is.
The report, titled Geo-mechanical Study Of Bowland Shale Seismicity, was commissioned by Cuadrilla Resources and carried out by a team of independent experts from across Europe, according to the company.
The report goes on to say the water-injection fracking technique is used more than 3km (about two miles) below ground and this ‘significantly reduces the likelihood of a seismic event of magnitude 3 or less on the Richter scale having any impact at all at the surface’.
The theoretical maximum seismic event of magnitude 3 would not present a risk to personal safety or damage to property on the surface, the report states.
It proposes an ‘early detection system’ to monitor seismic activity at Cuadrilla’s drilling site which would ‘build in an extra layer of safety’.
It proposes steps to reduce the chance of further tremors ‘exceeding safe limits’.
Fracking has also been blamed on spoiling water supplies by fluid used in the process seeping into underground waterways.
The report states fracking carried out by Cuadrilla in the Bowland basin occurs at a depth of around 3km, whereas groundwater aquifers do not exist beyond a depth of around 300metres (1,000ft).
The Frack Off protest at Cuadrilla’s drilling site was timed to ‘highlight the hypocrisy’ of the Shale Gas Environmental Summit in London today.
The campaign group said the event, sponsored by companies involved in the oil and gas industry, will try to promote rapid expansion into the untapped fossil fuel.
Campaigners are also expected to stage a ‘Frack Mob’ mass event outside the summit at 3pm. At the drill site in Lancashire six protesters climbed up the rig to erect a banner before police were called.
A spokeswoman for Lancashire Police said: ‘At around 5.30am around seven protesters gained entry to the Cuadrilla gas drilling site in Banks.
‘Six out of the seven have climbed up a rig on the site and have erected a banner.
‘One protester remains on the ground. Police are in attendance and a cordon has been put in place around the site. We are liaising with the site owners and the protesters to bring about a peaceful resolution.’
A spokesman for the company said they were assessing the situation and police had sealed off the rig.
Frack Off spokeswoman Jenny Boykin said: ‘Fracking uses huge amounts of water mixed with toxic chemicals, a large fraction of which are never recovered.
‘The fracking fluid also leaches chemicals like arsenic out of the rocks when it is used, making it even more toxic, and so the fluid that is recovered becomes a big disposal problem.
‘The contamination of irrigation water means that everyone’s food supplies could potentially be affected. Fracking in the United States has already resulted in numerous spills of these fluids.’
A spokesman from the Department of Energy and Climate Change said: ‘Cuadrilla’s geomechanical study was given to the Department of Energy and Climate Change today.
‘The implications of this report will be reviewed very carefully – in consultation with the British Geological Survey, independent experts, and the other key regulators, HSE and the Environment Agency – before any decision on the resumption of these hydraulic fracture operations is made.’
OPPOSITION TO FRACKING INTENSIFIES
Opposition to fracking is intensifying in Britain as the jury is still out on whether the controversial gas extraction process will poison drinking water and cause major environmental damage.
Energy companies have said the process is safe but environment groups warn it could pose human health risks.
Mark Miller, chief executive of Cuadrilla, has said the process does not pose a threat to UK groundwater.
But horror stories have emerged from the US, where fracking is common, including reports of tap water igniting when a match is lit and claims of contaminated water making people ill.
Such concerns have led to bans or moratoria on fracking in some places.
France has banned fracking from shale rock and New York state has introduced a moratorium.
Environmental groups in the UK have been calling for a moratorium at least until environmental and safety impacts have been addressed.
In Australia, ground water and soil contamination fears have led farmers and green groups to form an unlikely alliance against fracking.
Concerns have also been raised that fracking could pose a threat to Bath’s world-famous hot springs.
Bath and North East Somerset Council said in September that two resource companies have applied for planning permission to test- drill for gas but the council fears that, if allowed to go ahead, it could harm the springs.
_________________________
Special thanks to Richard Charter