A new report from Durham University shows fractures from fracking operations could extend to within 720 feet of the surface at Balcombe. The report concludes maximum fracture lengths at US frack sites is 588m, or 1928 feet.
Cuadrilla plans to drill at 2667 feet in Balcombe – a maximum fracture, therefore, would bring frack fluid to within two football pitches of the surface – and right through the water supply.
In November Cuadrilla admitted that faults such as the one that caused earthquakes in Lancashire may extend 2000 ft upwards (see p50 of linked pdf). Were the company to hit a similar structure in Balcombe this would bring fluids and gas even closer to the surface than man-made fractures. The fault that caused the earthquakes in Lancashire remains unidentified, despite two studies.
The report provides yet more evidence that fractures can extend close to the surface. In a ‘shallow frack’ such as Balcombe, the risks of fluid and gas migration are high. In their submission to parliament last year, Cuadrilla claimed fracking takes place at 5000 feet below the surface (see 6.3.11). No mention was made of Balcombe, which is scheduled to be be fracked at nearly half that depth.
Durham’s study undermines those who claim that Balcombe’s unique geology makes it exempt from comparisons with other frack sites. In fact every frack site is unique: this new study is important because it shows fracture lengths averaged across many different types of terrain.