The debate, between both the main participants and many of those who have left comments, is running on two tracks. One argument has developed about the nitty-gritty of shale-gas extraction. What the impact is not only of fracking but of all the associated requirements for extracting shale gas. Fracking merely releases shale gas from rocks far underground. Also in question is the integrity of wells and well-head equipment. Add to that disquiet over the use of the large quantities of water required and disposal of waste water and the heavy traffic that accompanies drilling each well (of which many are needed to extract gas at sufficient volumes) and the local effects start to add up.
The other disagreement is on the wider environmental impacts of investing in hydrocarbons. Gas may be cleaner than coal but would not the money be better spent on developing renewable sources of energy than building a reliance on gas by drilling wells, building distribution infrastructure and constructing more gas-fired power plants? Michael Brune echoes the thoughts of many who have left comments by saying that he reckons "pursuing shale gas means doubling down on exactly the sort of climate-disrupting energy source that, within our lifetimes, could cause a global climate catastrophe".