Just before Christmas (23rd December), we submitted evidence on the danger of fracking in Kent to a Commons Select Committee. The Environmental Audit Committee is undertaking an inquiry looking at the potential risks to water supplies and water quality, emissions, habitats and geological integrity.
We fear fracking could damage the aquifer which supplies 70% of the county’s water. The gas and oil deposits are no more than 600-700m below the aquifer, the Chalk of the North Downs. There is also a risk that geological faults in the area would be re-activated allowing gases and fracking fluids to leak into the chalk and so contaminate the water supply.
We recently published a detailed report on the water resource implications of shale gas and oil exploration and development in East Kent and the Weald. This has formed the basis of the submission to the Audit Committee.
We make the point that planes of structural weakness developed along fractures in the rocks allowed vertical slippages of up to 100m. These are the sites of earthquakes that occurred over a period of more than 200 million years but are still regarded as active, as evidenced by the Folkestone earthquake (magnitude 4.3) of 2007. There were also notable earthquakes in 1382, 1500 (when six people were killed), 1776 and 1950.
The licensed area, Woodnesborough, Tilmanstone and Shepherdswell, also features up to 10 public supply boreholes. These would be at risk in the event of any escape of contaminating fluids as a result of fracking operations.
Hydraulic fracturing involves injection of a water/sand/chemical mix (some of the constituents being hazardous or toxic) under high pressure in order to break up the shales and release the trapped methane. CPRE Kent is concerned that this process can also fracture and disrupt other adjacent rocks and re-activate the high angle faults creating new pathways for migration of gases and fracking fluids into the overlying Chalk, and from here into the soil and the springs and seepages feeding the tributary streams of the Rivers Great Stour, Little Stour and Dour. The Great and Little Stour support the irrigation of the areas of intensive agriculture below Canterbury. Contamination can also result from failures in the construction of the boreholes – casings and grout seals can suffer corrosion, rupture or fragmentation, providing additional opportunities for the migration of contaminants.
CPRE Kent Director Hilary Newport said: “We have submitted strong arguments backed by scientific evidence to the Environmental Audit Commission detailing our very serious concerns about fracking. We fear the potential danger to Kent’s water supply is too big a risk.
“We await with interest the Committee’s report and the Government’s response to it.”
The deadline for submissions was 31st December 2014. The Terms of Reference of the Environmental Audit Committee can be viewed here.
January 5th 2015