
A map showing spills sites in North Dakota over the ten years of the study
Higher numbers
The rapid growth in the extraction of oil and gas from unconventional sources in the US has had a massive impact on the production and consumption of energy over the past ten years. The key to this expansion has been the use of hydraulic fracturing, the process of injecting fluids with chemical additives under pressure to crack underground rock and release the trapped resources.
However, environmental campaigners have long been troubled by the potential for this process to contaminate water supplies and the environment through leaks and spills. A study carried out by the US Environment Protection Agency on fracking in eight states between 2006 and 2012 concluded that 457 spills had occurred.
But this new study, while limited to just four states with adequate data, suggests the level of spills is much higher. The researchers found 6,648 spills between 2005 and 2014.














Comment: Fracking chemicals are showing up in everyday items from toothpaste, detergents and ice cream
Fracking - you are not important
Fracking banned in Victoria, Australia
Holy frack: More concern arises over groundwater contamination from fracking