Fracking has been outed as the controversial killer of a rare and threatened species of fish. The shale gas extraction process has been blamed for killing off an entire population of the blackside dace fish in Kentucky, when chemical waste from the fracking site leaked into a river in 2007.
Fracking is a process of extracting the fossil fuel shale gas, by which chemicals are pumped at high pressure into the ground in order to break apart the rocks and release the gas within. Using a hydraulic drill, tiny explosions are used to shatter the rock and release the tiny bubbles of gas within, whilst a mixture of sand, chemicals and water is then injected into the fissures to allow the gas to escape out of the cavities.
The process is considered controversial and a divisive subject amongst communities based near to fracking sites. Concerns are regularly raised about the possibility of the chemicals used in the process making their way back into local drinking water supplies. Whilst the evidence for this is indeed rare, it seems that attention must also be focused on the harmful effects fracking may have on the local ecosystems surrounding the sites.
Indeed, in May and June 2007, the Acorn Fork Creek river in Kentucky, USA, was the unfortunate end destination of fracking chemicals, including hydrochloric acid, which leaked from an overflowing storage tank. Over two kilometres of river were polluted, and according to sources including the US Geological Society, all fish and wildlife in the contaminated area died.
Amongst those studying the devastation to the Acorn Fork Creek were Diana Papoulias of the US Geological Survey, and Anthony Velasco of the US Fish and Wildlife Service, Kentucky. In their analysis of the polluted section of river, they found severe lesions on the gills of many of the fish they examined, and indeed when healthy fish were introduced to the contaminated water, these subjects developed lesions in a matter of hours, indicating strongly that the fracking chemicals were very likely the cause of the harm to the wildlife.
One of the species of fish affected by the disaster was the blackside dace, which exists only in a handful of locations in the wild, including the Acorn Fork Creek. In the sections of river which were most heavily affected by the chemicals, Velasco and Papoulias found no blackfish dace which had survived. Further along the river, the dace were displaying unusual behaviour, such as moving slowly back and forth.
Speaking about their findings, Papoulias said: “Our study is a precautionary tale of how entire populations could be put at risk even with small-scale fluid spills.”