Wikipedia‘s definition of fracking is:
“Hydraulic fracturing (also hydrofracturing, hydrofracking, fracking or fraccing) is a well-stimulation technique in which rock is fractured by a pressurized liquid. The process involves the high-pressure injection of ‘fracking fluid’ (primarily water, containing sand or other proppants suspended with the aid of thickening agents) into a wellbore to create cracks in the deep-rock formations through which natural gas, petroleum, and brine will flow more freely. When the hydraulic pressure is removed from the well, small grains of hydraulic fracturing proppants (either sand or aluminium oxide) hold the fractures open.”
The research papers and evidence that is continually being released related to fracking is highly concerning. Health effects, climate change connections and water contamination are just a few of the growing list of disturbing flags this fossil fuel exploitation is producing. Rather than reinvent the wheel as such, you can find concise writings over at Refracktion on many of the risks.
The 2015 British Medact report on fracking was a comprehensive review of health-related evidence, with the well-respected authors and signatories to a letter to the British Medical Journal stating: “Fracking is an inherently risky activity that produces hazardous levels of air and water pollution that can have adverse impacts on health. The heavy traffic, noise and odour that accompanies fracking, as well as the socially disruptive effects of temporary ‘boomtowns’ and the spoilage of the natural environment are additional health hazards… The arguments against fracking on public health and ecological grounds are overwhelming. There are clear grounds for adopting the precautionary principle and prohibiting fracking.”