The company behind the UK's first shale gas well in Lancashire has insisted its ongoing plan to extract gas lying 10,000 feet below the ground through a process known as hydraulic fracturing - or 'fracking' - is safe.
Hydraulic fracturing is a process where millions of gallons of water, sand and chemicals are pumped underground to break apart rock formations and release gas.
Experts have expressed concern that the chemicals used in fracking may pose a threat to underground water supplies or when waste fluids are transported or spilled. In the US, where the industry has been bitterly opposed, the Environmental Protection Agency (EPA) has recently launched its own investigation into the risks.
Despite the concerns there has been a surge of interest around Europe to begin extraction, with exploratory drilling already underway in Poland, Bulgaria, France, Germany, the Netherlands, Sweden, Ukraine and the UK. It is seen as an important development for reducing European reliance on imported gas supplies.
Cuadrilla Resources, which has already begun exploratory drilling at sites near Blackpool in Lancashire, said the controversial 'fracking' process was a commonly-used technique within the oil and gas industry.
'We're not really using unconventional technology,' CEO Mark Miller told MPs from the Energy and Climate Change Committee. 'Shale gas exploration techniques, including hydraulic fracture, are conventional and have been used across the oil and gas industry for many decades. It is the reservoir source in which the gas is found that is unconventional.'
The extraction process requires large amounts of water, approximately 13,000 cubic meters for each well it drills. Cuadrilla said it would obtain all its supplies from the local water company, United Untilies. It admitted it did not yet know if the fracking liquid that returned to the surface after hydraulic fracturing would be able to be disposed of immediately or if it would first need to be treated, to remove chemicals. The company told MPs any disposed water would be kept in a steel tank to protect against spillage risk.
Miller told MPs it would be 'near-impossible' for any of the fracking liquid pumped underground to breach the well and contaminate any underground water aquifers. If there was any break in the well wall, he said, they could repair it within three to five days. Miller also said the company was testing the surrounding soils, streams and air to provide a baseline in case of any future claims about contamination from the site.
Speaking later to MPs, Jonathan Craig from the Geological Society argued that the exploitation of shale gas reserves in UK, Europe and around the world could reduce the pressure to push for fossil fuels in the Arctic. In the case of the UK, he also said it could also reduce its dependency on burning coal to produce electricity, which produces comparatively more carbon emissions than gas.
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